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Sample records for high-q microring resonator

  1. Thermal nonlinear effect in high Q factor silicon-on-insulator microring resonator

    NASA Astrophysics Data System (ADS)

    Xiaogang, Tong; Jun, Liu; Chenyang, Xue

    2017-07-01

    In this paper, all-optical switching in silicon-on-insulator (SOI) serially coupled ring resonator based on thermal nonlinear effect is proposed. The radii of the silicon microring resonator are 10 μm. In experiment, firstly measured by single pump injection technology with vertical coupling surface grating coupler method, the highest notch of serially coupled ring resonator is 17 dB. The strong transverse light-confinement nature of the resonator induces nonlinear optical response with low pump power. Thermal nonlinear effect is achieved by controlling the power of the continuous-wave (CW) pump with very low tuning threshold (0.33 nm). And the slop of resonant wavelength as a function of injected pump is 220 pm/mw. Secondly, switching time measured by two pump injection technology is 3.01 μs and 1.03 μs, respectively. Which could be used in integrated photonic communication circuits based optical logic and slow-light structure.

  2. A platform for multiplexed sensing of biomolecules using high-Q microring resonator arrays with differential readout and integrated microfluidics

    NASA Astrophysics Data System (ADS)

    Wright, J. B.; Brener, I.; Westlake, K. R.; Branch, D. W.; Shaw, M. J.; Vawter, G. A.

    2010-02-01

    We demonstrate chemical/biological sensor arrays based on high quality factor evanescent microring waveguide resonators in a process that is compatible with CMOS fabrication, glass microfluidic integration, and robust surface chemistry ligand attachment. We cancel out any fluctuations due to liquid temperature variations through a differential dual sensor design. Using laser locking servo techniques we attain detection sensitivities in the ng/ml range. This combination of silicon photonic sensors, robust packaging, high sensitivity and arrayed design is capable of providing a platform for multiplexed chem-bio sensing of molecules suspended in solution.

  3. High Q micro-ring resonators fabricated from polycrystalline aluminum nitride films for near infrared and visible photonics.

    PubMed

    Pernice, Wolfram H P; Xiong, Chi; Tang, Hong X

    2012-05-21

    We demonstrate wideband integrated photonic circuits in sputter-deposited aluminum nitride (AlN) thin films. At both near-infrared and visible wavelengths, we achieve low propagation loss in integrated waveguides and realize high-quality optical resonators. In the telecoms C-band (1520-1580 nm), we obtain the highest optical Q factor of 440,000. Critical coupled devices show extinction ratio above 30 dB. For visible wavelengths (around 770 nm), intrinsic quality factors in excess of 30,000 is demonstrated. Our work illustrates the potential of AlN as a low loss material for wideband optical applications.

  4. Polymer microring resonators and their sensor applications

    NASA Astrophysics Data System (ADS)

    Guo, L. Jay; Maxwell, Adam; Chao, Chung-Yen; Ling, Tao; Kim, Jin-Sung; Huang, Sheng-Wen; Ashkenazi, Shai

    2008-02-01

    Photonic microring resonators have great potential in the application of highly sensitive label-free biosensors and detection of high-frequency ultrasound due to high Q-factor resonances. Design consideration, device fabrication techniques, experimental results are report in this paper.

  5. Advanced Silicon Microring Resonator Devices for Optical Signal Processing

    NASA Astrophysics Data System (ADS)

    Masilamani, Ashok Prabhu

    Chip level optical interconnects has gained momentum with recent demonstrations of silicon-on-insulator (SOI) based photonic modules such as lasers, modulators, wavelength division multiplexing (WDM) filters, etc. A fundamental building block that has enabled many of these silicon photonic modules is the compact, high Q factor microring resonator cavity. However, most of these demonstrations have WDM processing components based on simple add-drop filters that cannot realize the dense WDM systems required for the chip level interconnects. Dense WDM filters have stringent spectral shape requirements such as flat-top filter passband, steep band transition etc. Optical filters that can meet these specifications involve precise placement of the poles and zeros of the filter transfer function. Realization of such filters requires the use of multiple coupled microring resonators arranged in complex coupling topologies. In this thesis we have proposed and demonstrated new multiple coupled resonator topologies based on compact microring resonators in SOI material system. First we explored novel microring architectures which resulted in the proposal of two new coupled microring architectures, namely, the general 2D microring array topology and the general cascaded microring network topology. We also developed the synthesis procedures for these two microring architectures. The second part of this thesis focussed on the demonstration of the proposed architectures in the SOI material system. To accomplish this, a fabrication process for SOI was developed at the UofA Nanofab facility. Using this process, ultra-compact single microring filters with microring radii as small as 1mum were demonstrated. Higher order filter demonstration with multiple microrings necessitated post-fabrication microring resonance tuning. We developed additional fabrication steps to install micro heaters on top of the microrings to thermally tune its resonance. Subsequently, a thermally tuned fourth

  6. High Q Miniature Sapphire Acoustic Resonator

    NASA Technical Reports Server (NTRS)

    Wang, Rabi T.; Tjoelker, R. L.

    2010-01-01

    We have demonstrated high Q measurements in a room temperature Miniature Sapphire Acoustic Resonator (MSAR). Initial measurements of bulk acoustic modes in room temperature sapphire at 39 MHz have demonstrated a Q of 8.8 x 10(exp 6). The long term goal of this work is to integrate such a high Q resonator with small, low noise quartz oscillator electronics, providing a fractional frequency stability better than 1 x 10(exp -14) @ 1s.

  7. High Q silica microbubble resonators

    NASA Astrophysics Data System (ADS)

    Farnesi, D.; Barucci, A.; Berneschi, S.; Brenci, M.; Cosi, F.; Nunzi Conti, G.; Pelli, S.; Righini, G. C.; Soria, S.

    2012-01-01

    Microbubble resonators (MBRs) combine the unique properties of whispering gallery mode resonators with the intrinsic capability of integrated microfluidics. Here an improved fabrication method of MBRs is presented, based on the heating of a slightly pressurized capillary by a rotating arc discharge. Rotation of the electrodes ensures an homogeneous distribution of the heat all over the capillary surface. The demonstrated MBRs have Q factors up to 107 at 773 nm. Microbubbles were filled with water and aqueous solutions of ethanol in order to test the refractive index sensing capabilities of such resonators, which also show a good temporal stability.

  8. Flexible chalcogenide glass microring resonator for mid-infrared emission

    NASA Astrophysics Data System (ADS)

    Wang, Liangliang; Li, Lijing; Sun, Mingjie

    2016-10-01

    Emerging applications in communication, sensing, medical, and many other fields call for on-chip microring laser, however, the method to make it work at mid-infrared still need to be explored. In this paper, a microring resonator integrated in flexible substrate is designed and evaluated, with high Q-factor ( 105) at pump and signal wavelengths, achieving emission in mid-infrared (3.6μm) using rare earth doped chalcogenide glass. Furthermore, the strain-optical coupling in multilayer flexible materials is numerically verified, and a 0.3 nm/μɛ resonance wavelength shift is achieved by local neutral axis theory, without significant loss of flexible device performance.

  9. Silicon hybrid plasmonic microring resonator for sensing applications.

    PubMed

    Zhang, Meng; Wu, Genzhu; Chen, Daru

    2015-08-10

    A novel silicon hybrid plasmonic microring resonator consisting of a silver nanoring on top of a silicon-on-insulator ring is proposed and investigated theoretically for possible applications in sensing at the deep subwavelength scale. By using the finite-element method, insight into how the mode properties (Q factor, effective mode volume, energy ratio, sensitivity) depend on the geometric structure of the hybrid microring resonator is presented. Simulation results reveal that this kind of hybrid microcavity maintains a high Q factor ∼600, an ultrasmall mode volume of 0.15  μm3, and high sensitivity of 497  nm/refractive index unit for refractive index sensing. The hybrid plasmonic microcavity with optimized geometric structures presented provides the potential for ultracompact sensing applications.

  10. Biosensing Using Microring Resonator Interferograms

    PubMed Central

    Hsu, Shih-Hsiang; Yang, Yung-Chia; Su, Yu-Hou; Wang, Sheng-Min; Huang, Shih-An; Lin, Ching-Yu

    2014-01-01

    Optical low-coherence interferometry (OLCI) takes advantage of the variation in refractive index in silicon-wire microring resonator (MRR) effective lengths to perform glucose biosensing using MRR interferograms. The MRR quality factor (Q), proportional to the effective length, could be improved using the silicon-wire propagation loss and coupling ratio from the MRR coupler. Our study showed that multimode interference (MMI) performed well in broad band response, but the splitting ratio drifted to 75/25 due to the stress issue. The glucose sensing sensitivity demonstrated 0.00279 meter per refractive-index-unit (RIU) with a Q factor of ∼30,000 under transverse electric polarization. The 1,310 nm DFB laser was built in the OLCI system as the optical ruler achieving 655 nm characterization accuracy. The lowest sensing limitation was therefore 2 × 10−4 RIU. Moreover, the MRR effective length from the glucose sensitivity could be utilized to experimentally demonstrate the silicon wire effective refractive index with a width of 0.45 μm and height of 0.26 μm. PMID:24434876

  11. Biosensing using microring resonator interferograms.

    PubMed

    Hsu, Shih-Hsiang; Yang, Yung-Chia; Su, Yu-Hou; Wang, Sheng-Min; Huang, Shih-An; Lin, Ching-Yu

    2014-01-10

    Optical low-coherence interferometry (OLCI) takes advantage of the variation in refractive index in silicon-wire microring resonator (MRR) effective lengths to perform glucose biosensing using MRR interferograms. The MRR quality factor (Q), proportional to the effective length, could be improved using the silicon-wire propagation loss and coupling ratio from the MRR coupler. Our study showed that multimode interference (MMI) performed well in broad band response, but the splitting ratio drifted to 75/25 due to the stress issue. The glucose sensing sensitivity demonstrated 0.00279 meter per refractive-index-unit (RIU) with a Q factor of ~30,000 under transverse electric polarization. The 1,310 nm DFB laser was built in the OLCI system as the optical ruler achieving 655 nm characterization accuracy. The lowest sensing limitation was therefore 2 × 10-4 RIU. Moreover, the MRR effective length from the glucose sensitivity could be utilized to experimentally demonstrate the silicon wire effective refractive index with a width of 0.45 mm and height of 0.26 mm.

  12. C-band swept wavelength erbium-doped fiber laser with a high-Q tunable interior-ridge silicon microring cavity.

    PubMed

    Li, Nanxi; Timurdogan, Erman; Poulton, Christopher V; Byrd, Matthew; Magden, Emir Salih; Su, Zhan; Purnawirman; Leake, Gerald; Coolbaugh, Douglas D; Vermeulen, Diedrik; Watts, Michael R

    2016-10-03

    We demonstrate swept-wavelength operation of an erbium-doped fiber laser using a tunable silicon microring cavity. The microring cavity is designed to have 35 nm free spectral range, a high Q of 1.5 × 105, and low insertion loss of <0.05 dB. The resonance wavelength of the cavity is tuned efficiently (8.1μW/GHz) and rapidly (τr,f~2.2μs) using an embedded Si heater. The laser achieves single-mode continuous-wave emission over the C-band (1530 nm-to-1560 nm). A mean swept-wavelength rate of 22,600 nm/s or 3106 THz/s is demonstrated within 1532 nm-to-1542 nm wavelength range. Its linewidth is measured to be 16 kHz using loss-compensated circulating delayed self-heterodyne detection.

  13. Ammonia Optical Sensing by Microring Resonators

    PubMed Central

    Passaro, Vittorio M. N.; Dell'Olio, Francesco; De Leonardis, Francesco

    2007-01-01

    A very compact (device area around 40 μm2) optical ammonia sensor based on a microring resonator is presented in this work. Silicon-on-insulator technology is used in sensor design and a dye doped polymer is adopted as sensing material. The sensor exhibits a very good linearity and a minimum detectable refractive index shift of sensing material as low as 8×10-5, with a detection limit around 4 ‰. PMID:28903258

  14. Compact pulley-type microring resonator with high quality factor

    NASA Astrophysics Data System (ADS)

    Cai, Dong-Po; Lu, Jyun-Hong; Chen, Chii-Chang; Lee, Chien-Chieh; Lin, Chu-En; Yen, Ta-Jen

    2014-11-01

    A pulley-type microring resonator with ultra-small dimensions and ultra-high quality factor on a silicon-on-insulator wafer is fabricated and characterized. Simulation results show that the bending loss of the pulley-type microring resonator can be diminished by wrapping the curved waveguide around the microring, and that the energy loss from the output port can be decreased by tuning the width of the bus waveguide to achieve destructive interference. A quality factor of 1.73 × 105 is obtained in this experiment. The compact size of the pulley-type microring resonator with low bending loss is suitable for an integrated optical circuit.

  15. Photonic crystal microring resonator for label-free biosensing.

    PubMed

    Lo, Stanley M; Hu, Shuren; Gaur, Girija; Kostoulas, Yiorgos; Weiss, Sharon M; Fauchet, Philippe M

    2017-03-20

    A label-free optical biosensor based on a one-dimensional photonic crystal microring resonator with enhanced light-matter interaction is demonstrated. More than a 2-fold improvement in volumetric and surface sensing sensitivity is achieved compared to conventional microring sensors. The experimental bulk detection sensitivity is ~248nm/RIU and label-free detection of DNA and proteins is reported at the nanomolar scale. With a minimum feature size greater than 100nm, the photonic crystal microring resonator biosensor can be fabricated with the same standard lithographic techniques used to mass fabricate conventional microring resonators.

  16. PAM4 silicon photonic microring resonator-based transceiver circuits

    NASA Astrophysics Data System (ADS)

    Palermo, Samuel; Yu, Kunzhi; Roshan-Zamir, Ashkan; Wang, Binhao; Li, Cheng; Seyedi, M. Ashkan; Fiorentino, Marco; Beausoleil, Raymond

    2017-02-01

    Increased data rates have motivated the investigation of advanced modulation schemes, such as four-level pulseamplitude modulation (PAM4), in optical interconnect systems in order to enable longer transmission distances and operation with reduced circuit bandwidth relative to non-return-to-zero (NRZ) modulation. Employing this modulation scheme in interconnect architectures based on high-Q silicon photonic microring resonator devices, which occupy small area and allow for inherent wavelength-division multiplexing (WDM), offers a promising solution to address the dramatic increase in datacenter and high-performance computing system I/O bandwidth demands. Two ring modulator device structures are proposed for PAM4 modulation, including a single phase shifter segment device driven with a multi-level PAM4 transmitter and a two-segment device driven by two simple NRZ (MSB/LSB) transmitters. Transmitter circuits which utilize segmented pulsed-cascode high swing output stages are presented for both device structures. Output stage segmentation is utilized in the single-segment device design for PAM4 voltage level control, while in the two-segment design it is used for both independent MSB/LSB voltage levels and impedance control for output eye skew compensation. The 65nm CMOS transmitters supply a 4.4Vppd output swing for 40Gb/s operation when driving depletion-mode microring modulators implemented in a 130nm SOI process, with the single- and two-segment designs achieving 3.04 and 4.38mW/Gb/s, respectively. A PAM4 optical receiver front-end is also described which employs a large input-stage feedback resistor transimpedance amplifier (TIA) cascaded with an adaptively-tuned continuous-time linear equalizer (CTLE) for improved sensitivity. Receiver linearity, critical in PAM4 systems, is achieved with a peak-detector-based automatic gain control (AGC) loop.

  17. Tunable Fano resonance in mutually coupled micro-ring resonators

    NASA Astrophysics Data System (ADS)

    Xiao, Huifu; Wu, Xiaosuo; Liu, Zilong; Zhao, Guolin; Guo, Xiaonan; Meng, Yinghao; Deng, Lin; Chen, Wenping; Tian, Yonghui; Yang, Jianhong

    2017-08-01

    We simulate and experimentally observe a tunable Fano resonance in a mutual coupling micro-ring resonator (MRR) system which is comprised of two cascaded micro-ring resonators. The scattering matrix model is employed to analyze the modulating characterization of the Fano resonance by changing the effective refractive index of MRRs, and the simulation results indicate that the Fano resonance is the sharpest when two MRRs' resonances are coincident. The Fano resonance device is fabricated on a silicon-on-insulator substrate using the standard complementary metal-oxide-semiconductor (CMOS) fabrication process. The experimental results show that the spectrum of the Fano resonance can be periodically tuned and flipped by applying forward-bias voltages to integrated micro-heaters above the MRRs. The proposed device has unique merits such as compact size, simple structure, CMOS compatible fabrication process, and large-scale integration, which is a promising candidate for high-sensitivity biochemical sensing and low power optical switching/modulating in future.

  18. A Microring Resonator Sensor for Sensitive Detection of 1,3,5-Trinitrotoluene (TNT)

    PubMed Central

    Orghici, Rozalia; Lützow, Peter; Burgmeier, Jörg; Koch, Jan; Heidrich, Helmut; Schade, Wolfgang; Welschoff, Nina; Waldvogel, Siegfried

    2010-01-01

    A microring resonator sensor device for sensitive detection of the explosive 1,3,5-trinitrotoluene (TNT) is presented. It is based on the combination of a silicon microring resonator and tailored receptor molecules. PMID:22163576

  19. High Q silicon carbide microdisk resonator

    SciTech Connect

    Lu, Xiyuan; Lee, Jonathan Y.; Feng, Philip X.-L.; Lin, Qiang

    2014-05-05

    We demonstrate a silicon carbide (SiC) microdisk resonator with optical Q up to 5.12 × 10{sup 4}. The high optical quality, together with the diversity of whispering-gallery modes and the tunability of external coupling, renders SiC microdisk a promising platform for integrated quantum photonics applications.

  20. Mach-Zehnder wavelength selective switch embedded with microring resonators

    NASA Astrophysics Data System (ADS)

    Miura, Kengo; Shoji, Yuya; Mizumoto, Tetsuya

    2017-02-01

    A wavelength selective switch is proposed for optical wavelength division multiplexing network applications with very short range interconnections. The proposed device uses a Mach-Zehnder interferometer configuration incorporating wavelength selective phase shifters composed of microring resonators between their two arms. Wavelength selectivity is provided by cascaded microring resonators, which are placed in proximity so that the increase in excess loss caused by the difference in resonant wavelengths can be minimized. An on/off switching ratio >20 dB is obtainable when the drop/through transmittance ratio of the cascaded microring resonators is >22 dB and the coupling efficiency deviation from 50% is <1% in the directional couplers constructing the Mach-Zehnder interferometer.

  1. Highly sensitive detection using microring resonator and nanopores

    NASA Astrophysics Data System (ADS)

    Bougot-Robin, K.; Hoste, J. W.; Le Thomas, N.; Bienstman, P.; Edel, J. B.

    2016-04-01

    One of the most significant challenges facing physical and biological scientists is the accurate detection and identification of single molecules in free-solution environments. The ability to perform such sensitive and selective measurements opens new avenues for a large number of applications in biological, medical and chemical analysis, where small sample volumes and low analyte concentrations are the norm. Access to information at the single or few molecules scale is rendered possible by a fine combination of recent advances in technologies. We propose a novel detection method that combines highly sensitive label-free resonant sensing obtained with high-Q microcavities and position control in nanoscale pores (nanopores). In addition to be label-free and highly sensitive, our technique is immobilization free and does not rely on surface biochemistry to bind probes on a chip. This is a significant advantage, both in term of biology uncertainties and fewer biological preparation steps. Through combination of high-Q photonic structures with translocation through nanopore at the end of a pipette, or through a solid-state membrane, we believe significant advances can be achieved in the field of biosensing. Silicon microrings are highly advantageous in term of sensitivity, multiplexing, and microfabrication and are chosen for this study. In term of nanopores, we both consider nanopore at the end of a nanopipette, with the pore being approach from the pipette with nanoprecise mechanical control. Alternatively, solid state nanopores can be fabricated through a membrane, supporting the ring. Both configuration are discussed in this paper, in term of implementation and sensitivity.

  2. Slope tunable Fano resonances in asymmetric embedded microring resonators

    NASA Astrophysics Data System (ADS)

    Wang, Gencheng; Dai, Tingge; Jiang, Jianfei; Yu, Hui; Hao, Yinlei; Wang, Yuehai; Li, Yubo; Jiang, Xiaoqing; Yang, Jianyi

    2017-02-01

    An asymmetric embedded microring resonant system is proposed and fabricated on a silicon-on-insulator (SOI) to achieve slope tunable Fano resonances. The Fano resonances originate from the nonlinear phase shift produced by adding an inner ring coupling with the outer ring. The slope of the Fano resonance can be well tuned to be ultra-high by controlling the microheaters to adjust the phase condition. Experimentally, we observe Fano resonance with a maximum extinction ratio of about 40 dB, and the slope can be tuned from -35 dB nm-1 to -93 dB nm-1, which shows good agreement with the theoretical analysis. This device could find potential applications in ultra-high sensitivity sensing systems.

  3. Asymmetric Fano resonance in eye-like microring system

    NASA Astrophysics Data System (ADS)

    Qiu, Chen; Yu, Ping; Hu, Ting; Wang, Fan; Jiang, Xiaoqing; Yang, Jianyi

    2012-07-01

    In this paper, the Fano resonance in the "eye-like" microring resonator system (EMRS) is theoretically and experimentally investigated. The asymmetric Fano-resonance line shape of EMRS is generated by adding a microring inside and coupling with the outer ring to produce a nonlinear phase shift. The EMRS was fabricated on silicon-on-insulator wafer by the complementary metal-oxide-semiconductor compatible process. Compared to the conventional single-stage microring add-drop filter structure, the maximum sharpness of the transmission of the drop port is enhanced 3 times, and the drop port extinction ratio is increased by about 20 dB. The experimental results are in good agreement with the theoretical analysis.

  4. Efficient absorption by monolayer graphene in microring resonator

    NASA Astrophysics Data System (ADS)

    Liu, Ziyu

    2017-06-01

    We demonstrate a graphene photodetector based on a SOI microring resonator. The absorption of the graphene was enhanced by the resonating, so to improve the detection efficiency by 5 times. The impact of graphene’s position and length on the absorption rate was also been studied. The frequency selective effect shows the potential on spectrum detection and WDM photoelectric conversion.

  5. Low-threshold bistability in nonlinear microring tower resonator.

    PubMed

    Shafiei, Mehdi; Khanzadeh, Mohammad

    2010-12-06

    Microring tower resonators, which are a chain of microring resonators stacked on top of each other, are of great interest for nonlinear optics due to their unique features such as very high compactness, coupling efficiency and quality factor. In this research, we investigate the optical bistability in microring tower (MRT) with Kerr nonlinearity by using the coupled mode theory, and demonstrate how a proper defect into the structure can lead to low threshold bistability. In particular, we observed optical bistability in nonlinear defect modes with switching power as low as 165 μW through numerical calculations in a structure with a overall loss on the order of 0.01 mm. In addition, we also develop an analytical model that excellently gives the position of defect modes in linear regime.

  6. Properties of regular polygons of coupled microring resonators

    NASA Astrophysics Data System (ADS)

    Chremmos, Ioannis; Uzunoglu, Nikolaos

    2007-11-01

    The resonant properties of a closed and symmetric cyclic array of N coupled microring resonators (coupled-microring resonator regular N-gon) are for the first time determined analytically by applying the transfer matrix approach and Floquet theorem for periodic propagation in cylindrically symmetric structures. By solving the corresponding eigenvalue problem with the field amplitudes in the rings as eigenvectors, it is shown that, for even or odd N, this photonic molecule possesses 1 + N/2 or 1+N resonant frequencies, respectively. The condition for resonances is found to be identical to the familiar dispersion equation of the infinite coupled-microring resonator waveguide with a discrete wave vector. This result reveals the so far latent connection between the two optical structures and is based on the fact that, for a regular polygon, the field transfer matrix over two successive rings is independent of the polygon vertex angle. The properties of the resonant modes are discussed in detail using the illustration of Brillouin band diagrams. Finally, the practical application of a channel-dropping filter based on polygons with an even number of rings is also analyzed.

  7. Ultra-high Q even eigenmode resonance in terahertz metamaterials

    SciTech Connect

    Al-Naib, Ibraheem Dignam, Marc M.; Yang, Yuping; Zhang, Weili; Singh, Ranjan

    2015-01-05

    We report the simultaneous excitation of the odd and the even eigenmode resonances in a periodic array of square split-ring resonators, with four resonators per unit cell. When the electric field is parallel to their gaps, only the two well-studied odd eigenmodes are excited. As the resonators are rotated relative to one another, we observe the emergence and excitation of an extremely sharp even eigenmode. In uncoupled split-ring resonators, this even eigenmode is typically radiative in nature with a broad resonance linewidth and low Q-factor. However, in our coupled system, for specific range of rotation angles, our simulations revealed a remarkably high quality factor (Q ∼ 100) for this eigenmode, which has sub-radiant characteristics. This type of quad-supercell metamaterial offers the advantage of enabling access to all the three distinct resonance features of the split-ring resonator, which consists of two odd eigenmodes in addition to the high-Q even eigenmode, which could be exploited for high performance multiband filters and absorbers. The high Q even eigenmode could find applications in designing label free bio-sensors and for studying the enhanced light matter interaction effects.

  8. Planar coupling to high-Q lithium niobate disk resonators.

    PubMed

    Nunzi Conti, G; Berneschi, S; Cosi, F; Pelli, S; Soria, S; Righini, G C; Dispenza, M; Secchi, A

    2011-02-14

    We demonstrate optical coupling to high-Q lithium niobate disks from an integrated lithium niobate waveguide. The waveguides are made by proton exchange in X-cut lithium niobate substrate. The disks with diameter of 4.7 mm and thickness of 1 mm are made from commercial Z-cut lithium niobate wafers by polishing the edges into a spheroidal profile. Both resonance linewidth and cavity ringdown measurements were performed to calculate the Q factor of the resonator, which is in excess of 10(8). Planar coupling represents the most promising technique for practical applications of whispering gallery mode resonators.

  9. Engineered Carbon Nanotube Materials for High-Q Nanomechanical Resonators

    NASA Technical Reports Server (NTRS)

    Choi, Daniel S.; Hunt, Brian; Bronikowski, Mike; Epp, Larry; Hoenk, Michael; Hoppe, Dan; Kowalczyk, Bob; Wong, Eric; Xu, Jimmy; Adam, Douglas; Young, Rob

    2003-01-01

    This document represents a presentation offered by the Jet Propulsion Laboratory, with assistance from researchers from Brown University and Northrop Grumman. The presentation took place in Seoul, Korea in July 2003 and attempted to demonstrate the fabrication approach regarding the development of high quality factor (high-Q) mechanical oscillators (in the forms of a tunable nanotube resonator and a nanotube array radio frequency [RF] filter) aimed at signal processing and based on carbon nanotubes. The presentation also addressed parallel efforts to develop both in-plane single nanotube resonators as well as vertical array power devices.

  10. Modeling of Yb3+/Er3+-codoped microring resonators

    NASA Astrophysics Data System (ADS)

    Vallés, Juan A.; Gălătuş, Ramona

    2015-03-01

    The performance of a highly Yb3+/Er3+-codoped phosphate glass add-drop microring resonator is numerically analyzed. The model assumes resonant behaviour of both pump and signal powers and the dependences of pump intensity build-up inside the microring resonator and of the signal transfer functions to the device through and drop ports are evaluated. Detailed equations for the evolution of the rare-earth ions levels population densities and the propagation of the optical powers inside the microring resonator are included in the model. Moreover, due to the high dopant concentrations considered, the microscopic statistical formalism based on the statistical average of the excitation probability of the Er3+ ion in a microscopic level has been used to describe energy-transfer inter-atomic mechanisms. Realistic parameters and working conditions are used for the calculations. Requirements to achieve amplification and laser oscillation within these devices are obtainable as a function of rare earth ions concentration and coupling losses.

  11. Compact silicon hybrid plasmonic microring resonator-based polarization demultiplexer

    NASA Astrophysics Data System (ADS)

    Xu, Yin; Xiao, Jinbiao

    2015-08-01

    A compact silicon-based polarization demultiplexer (P-DEMUX) composed of a microring resonator in hybrid plasmonic waveguides and two bus channels in silicon wires is proposed and characterized. The modal analysis shows that the behaviors of TE modes for the hybrid plasmonic microring and silicon wire are similar, while those of TM modes illustrate significant difference, leading to strong polarization-dependence. As a result, the input TE mode can output from the drop port at the resonant wavelength while the input TM mode directly outputs from the through port with nearly neglected coupling. The present P-DEMUX can be easily applied to construct on-chip wavelength/polarization division multiplexing, further increasing the capacity of the interconnect system. Results show that a compact P-DEMUX is achieved, where the radius of the microring in the center is only 2.042 µm, and the extinction ratio and insertion loss are, respectively, ∼18.04 (19.89) and ∼0.61 (0.42) dB for TE (TM) mode, at the wavelength of 1550 nm. In addition, fabrication tolerances to the structural parameters are analyzed in detail and the evolution of the input field through the proposed P-DEMUX is also presented.

  12. Design and modeling of flower like microring resonator

    NASA Astrophysics Data System (ADS)

    Razaghi, Mohammad; Laleh, Mohammad Sayfi

    2016-05-01

    This paper presents a novel multi-channel optical filter structure. The proposed design is based on using a set of microring resonators (MRRs) in new formation, named flower like arrangement. It is shown that instead of using 18 MRRs, by using only 5 MRRs in recommended formation, same filtering operation can be achieved. It is shown that with this structure, six filters and four integrated demultiplexers (DEMUXs) are obtained. The simplicity, extensibility and compactness of this structure make it usable in wavelength division multiplexing (WDM) networks. Filter's characteristics such as shape factor (SF), free spectral range (FSR) and stopband rejection ratio can be designed by adjusting microrings' radii and coupling coefficients. To model this structure, signal flow graph method (SFG) based on Mason's rule is used. The modeling method is discussed in depth. Furthermore, the accuracy and applicability of this method are verified through examples and comparison with other modeling schemes.

  13. Optomechanically induced non-reciprocity in microring resonators.

    PubMed

    Hafezi, Mohammad; Rabl, Peter

    2012-03-26

    We describe a new approach for on-chip optical non-reciprocity which makes use of strong optomechanical interaction in microring resonators. By optically pumping the ring resonator in one direction, the optomechanical coupling is only enhanced in that direction, and consequently, the system exhibits a non-reciprocal response. For different configurations, this system can function either as an optical isolator or a coherent non-reciprocal phase shifter. We show that the operation of such a device on the level of single-photon could be achieved with existing technology.

  14. Preventing Raman Lasing in High-Q WGM Resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry; Maleki, Lute

    2007-01-01

    A generic design has been conceived to suppress the Raman effect in whispering- gallery-mode (WGM) optical resonators that have high values of the resonance quality factor (Q). Although it is possible to exploit the Raman effect (even striving to maximize the Raman gain to obtain Raman lasing), the present innovation is intended to satisfy a need that arises in applications in which the Raman effect inhibits the realization of the full potential of WGM resonators as frequency-selection components. Heretofore, in such applications, it has been necessary to operate high-Q WGM resonators at unattractively low power levels to prevent Raman lasing. (The Raman-lasing thresholds of WGM optical resonators are very low and are approximately proportional to Q(sup -2)). Heretofore, two ways of preventing Raman lasting at high power levels have been known, but both entail significant disadvantages: A resonator can be designed so that the optical field is spread over a relatively large mode volume to bring the power density below the threshold. For any given combination of Q and power level, there is certain mode volume wherein Raman lasing does not start. Unfortunately, a resonator that has a large mode volume also has a high spectral density, which is undesirable in a typical photonic application. A resonator can be cooled to the temperature of liquid helium, where the Raman spectrum is narrower and, therefore, the Raman gain is lower. However, liquid-helium cooling is inconvenient. The present design overcomes these disadvantages, making it possible to operate a low-spectral-density (even a single-mode) WGM resonator at a relatively high power level at room temperature, without risk of Raman lasing.

  15. Adaptive gain, equalization, and wavelength stabilization techniques for silicon photonic microring resonator-based optical receivers

    NASA Astrophysics Data System (ADS)

    Palermo, Samuel; Chiang, Patrick; Yu, Kunzhi; Bai, Rui; Li, Cheng; Chen, Chin-Hui; Fiorentino, Marco; Beausoleil, Ray; Li, Hao; Shafik, Ayman; Titriku, Alex

    2016-03-01

    Interconnect architectures based on high-Q silicon photonic microring resonator devices offer a promising solution to address the dramatic increase in datacenter I/O bandwidth demands due to their ability to realize wavelength-division multiplexing (WDM) in a compact and energy efficient manner. However, challenges exist in realizing efficient receivers for these systems due to varying per-channel link budgets, sensitivity requirements, and ring resonance wavelength shifts. This paper reports on adaptive optical receiver design techniques which address these issues and have been demonstrated in two hybrid-integrated prototypes based on microring drop filters and waveguide photodetectors implemented in a 130nm SOI process and high-speed optical front-ends designed in 65nm CMOS. A 10Gb/s powerscalable architecture employs supply voltage scaling of a three inverter-stage transimpedance amplifier (TIA) that is adapted with an eye-monitor control loop to yield the necessary sensitivity for a given channel. As reduction of TIA input-referred noise is more critical at higher data rates, a 25Gb/s design utilizes a large input-stage feedback resistor TIA cascaded with a continuous-time linear equalizer (CTLE) that compensates for the increased input pole. When tested with a waveguide Ge PD with 0.45A/W responsivity, this topology achieves 25Gb/s operation with -8.2dBm sensitivity at a BER=10-12. In order to address microring drop filters sensitivity to fabrication tolerances and thermal variations, efficient wavelength-stabilization control loops are necessary. A peak-power-based monitoring loop which locks the drop filter to the input wavelength, while achieving compatibility with the high-speed TIA offset-correction feedback loop is implemented with a 0.7nm tuning range at 43μW/GHz efficiency.

  16. High Q printed helical resonators for oscillators and filters.

    PubMed

    Everard, Jeremy K A; Broomfield, Carl D

    2007-09-01

    High Q compact printed helical resonators which operate from around 1.8 to 2 GHz are described. These consist of a multilayer printed circuit board (PCB) incorporating a printed helical transmission line. Loss in the via hole is reduced by ensuring that the standing wave current at this point is near zero. This ensures a significant increase in Q. Further increased energy storage per unit volume is achieved due to the 3-D helical nature of the resonator. Unloaded Qs of 235 and 195 have been obtained on low loss PCBs with dielectric constants of 2.2 and 10.5, respectively. Two applications for these resonators are described in this paper. The first is the design of a compact low noise oscillator where the ratio of QL/Q0, and hence insertion loss, is adjusted for low noise. The 2-GHz oscillator demonstrates a phase noise of -120 dBc/Hz at 10 kHz which is predicted exactly by the theory. The second is a three-section filter designed to offer the response required by the front end filter of a modern GSM mobile telephone. In the filter design three helical resonators are coupled together to produce a completely printed triplate bandpass filter.

  17. HIgh-Q Optical Micro-cavity Resonators as High Sensitive Bio-chemical and Ultrasonic Sensors

    NASA Astrophysics Data System (ADS)

    Ling, Tao

    device's Q factor has been realized by shifting the device's working wavelength to near-visible wavelength and further reducing the device's sidewall roughness. A record new high Q-˜x105 has been measured and the device's NEP as low as 21Pa has been measured. Furthermore, a smaller size polymer microring device has been developed and fabricated to realize larger angle beam forming applications.

  18. CMOS-compatible athermal silicon microring resonators.

    PubMed

    Guha, Biswajeet; Kyotoku, Bernardo B C; Lipson, Michal

    2010-02-15

    We propose a new class of resonant silicon optical devices, consisting of a ring resonator coupled to a Mach-Zehnder interferometer, which is passively temperature compensated by tailoring the optical mode confinement in the waveguides. We demonstrate operation of the device over a wide temperature range of 80 degrees. The fundamental principle behind this work can be extended to other photonic devices based on resonators such as modulators, routers, switches and filters.

  19. Detection of Salmonella bacterium in drinking water using microring resonator.

    PubMed

    Bahadoran, Mahdi; Noorden, Ahmad Fakhrurrazi Ahmad; Mohajer, Faeze Sadat; Abd Mubin, Mohamad Helmi; Chaudhary, Kashif; Jalil, Muhammad Arif; Ali, Jalil; Yupapin, Preecha

    2016-01-01

    A new microring resonator system is proposed for the detection of the Salmonella bacterium in drinking water, which is made up of SiO2-TiO2 waveguide embedded inside thin film layer of the flagellin. The change in refractive index due to the binding of the Salmonella bacterium with flagellin layer causes a shift in the output signal wavelength and the variation in through and drop port's intensities, which leads to the detection of Salmonella bacterium in drinking water. The sensitivity of proposed sensor for detecting of Salmonella bacterium in water solution is 149 nm/RIU and the limit of detection is 7 × 10(-4)RIU.

  20. Spontaneous four-wave mixing in lossy microring resonators

    NASA Astrophysics Data System (ADS)

    Vernon, Z.; Sipe, J. E.

    2015-05-01

    We develop a general Hamiltonian treatment of spontaneous four-wave mixing in a microring resonator side-coupled to a channel waveguide. The effect of scattering losses in the ring is included, as well as parasitic nonlinear effects including self- and cross-phase modulation. A procedure for computing the output of such a system for arbitrary parameters and pump states is presented. For the limit of weak pumping an expression for the joint spectral intensity of generated photon pairs, as well as the singles-to-coincidences ratio, is derived.

  1. Soft lithography replication of polymeric microring optical resonators.

    PubMed

    Huang, Yanyi; Paloczi, George; Scheuer, Jacob; Yariv, Amnon

    2003-10-06

    We have developed a soft lithography method to replicate polymeric integrated optical devices. In this method, the master device and the molded replica are made of the same materials, allowing direct comparison. To evaluate the quality of the replication, microring optical resonators are chosen as test devices because of their sensitivity to small fabrication errors. The master devices are precisely fabricated using direct electron beam lithography. The replicas are produced by the molding technique and subsequent ultraviolet curing. Compared with the master devices, the molded devices show minimal change in both physical shape and optical performance. This correspondence indicates the merits of soft lithographic methods for fabrication of precision integrated optical devices.

  2. All-plasmonic switching based on thermal nonlinearity in a polymer plasmonic microring resonator

    NASA Astrophysics Data System (ADS)

    Perron, David; Wu, Marcelo; Horvath, Cameron; Bachman, Daniel; van, Vien

    2011-07-01

    We experimentally investigated thermal nonlinear effects in a hybrid Au/SiO2/SU-8 plasmonic microring resonator for nonlinear switching. Large ohmic loss in the metal layer gave rise to a high rate of light-to-heat conversion in the plasmonic waveguide, causing an intensity-dependent thermo-optic shift in the microring resonance. We obtained 30 times larger resonance shift in the plasmonic microring than in a similar SU-8 dielectric microring. Using an in-plane pump-and-probe configuration, we also demonstrated all-plasmonic nonlinear switching in the plasmonic microring with an on--off switching contrast of 4dB over 50mW input power.

  3. Label-free virus detection using silicon photonic microring resonators.

    PubMed

    McClellan, Melinda S; Domier, Leslie L; Bailey, Ryan C

    2012-01-15

    Viruses represent a continual threat to humans through a number of mechanisms, which include disease, bioterrorism, and destruction of both plant and animal food resources. Many contemporary techniques used for the detection of viruses and viral infections suffer from limitations such as the need for extensive sample preparation or the lengthy window between infection and measurable immune response, for serological methods. In order to develop a method that is fast, cost-effective, and features reduced sample preparation compared to many other virus detection methods, we report the application of silicon photonic microring resonators for the direct, label-free detection of intact viruses in both purified samples as well as in a complex, real-world analytical matrix. As a model system, we demonstrate the quantitative detection of Bean pod mottle virus, a pathogen of great agricultural importance, with a limit of detection of 10 ng/mL. By simply grinding a small amount of leaf sample in buffer with a mortar and pestle, infected leaves can be identified over a healthy control with a total analysis time of less than 45 min. Given the inherent scalability and multiplexing capability of the semiconductor-based technology, we feel that silicon photonic microring resonators are well-positioned as a promising analytical tool for a number of viral detection applications.

  4. Label-free virus detection using silicon photonic microring resonators

    PubMed Central

    McClellan, Melinda S.; Domier, Leslie L; Bailey, Ryan C.

    2013-01-01

    Viruses represent a continual threat to humans through a number of mechanisms, which include disease, bioterrorism, and destruction of both plant and animal food resources. Many contemporary techniques used for the detection of viruses and viral infections suffer from limitations such as the need for extensive sample preparation or the lengthy window between infection and measurable immune response, for serological methods. In order to develop a method that is fast, cost-effective, and features reduced sample preparation compared to many other virus detection methods, we report the application of silicon photonic microring resonators for the direct, label-free detection of intact viruses in both purified samples as well as in a complex, real-world analytical matrix. As a model system, we demonstrate the quantitative detection of Bean pod mottle virus, a pathogen of great agricultural importance, with a limit of detection of 10 ng/mL. By simply grinding a small amount of leaf sample in buffer with a mortar and pestle, infected leaves can be identified over a healthy control with a total analysis time of less than 45 min. Given the inherent scalability and multiplexing capability of the semiconductor-based technology, we feel that silicon photonic microring resonators are well-positioned as a promising analytical tool for a number of viral detection applications. PMID:22138465

  5. Ammonia Optical Sensing by Microring Resonators.

    PubMed

    Passaro, Vittorio M N; Dell'Olio, Francesco; De Leonardis, Francesco

    2007-11-15

    A very compact (device area around 40 μm²) optical ammonia sensor based on amicroring resonator is presented in this work. Silicon-on-insulator technology is used insensor design and a dye doped polymer is adopted as sensing material. The sensor exhibitsa very good linearity and a minimum detectable refractive index shift of sensing materialas low as 8x10(-5), with a detection limit around 4 ‰.

  6. Development of silicon photonic microring resonator biosensors for multiplexed cytokine assays and in vitro diagnostics

    NASA Astrophysics Data System (ADS)

    Luchansky, Matthew Sam

    In order to guide critical care therapies that are personalized to a patient's unique disease state, a diagnostic or theranostic medical device must quickly provide a detailed biomolecular understanding of disease onset and progression. This detailed molecular understanding of cellular processes and pathways requires the ability to measure multiple analytes in parallel. Though many traditional sensing technologies for biomarker analysis and fundamental biological studies (i.e. enzyme-linked immunosorbent assays, real-time polymerase chain reaction, etc.) rely on single-parameter measurements, it has become increasingly clear that the inherent complexity of many human illnesses and pathways necessitates quantitative and multiparameter analysis of biological samples. Currently used analytical methods are deficient in that they often provide either highly quantitative data for a single biomarker or qualitative data for many targets, but methods that simultaneously provide highly quantitative analysis of many targets have yet to be adequately developed. Fields such as medical diagnostics and cellular biology would benefit greatly from a technology that enables rapid, quantitative and reproducible assays for many targets within a single sample. In an effort to fill this unmet need, this doctoral dissertation describes the development of a clinically translational biosensing technology based on silicon photonics and developed in the chemistry research laboratory of Ryan C. Bailey. Silicon photonic microring resonators, a class of high-Q optical sensors, represent a promising platform for rapid, multiparameter in vitro measurements. The original device design utilizes 32-ring arrays for real-time biomolecular sensing without fluorescent labels, and these optical biosensors display great potential for more highly multiplexed (100s-1000s) measurements based on the impressive scalability of silicon device fabrication. Though this technology can be used to detect a variety of

  7. Tunable Room Temperature THz Sources Based on Nonlinear Mixing in a Hybrid Optical and THz Micro-Ring Resonator

    PubMed Central

    Sinha, Raju; Karabiyik, Mustafa; Al-Amin, Chowdhury; Vabbina, Phani K.; Güney, Durdu Ö.; Pala, Nezih

    2015-01-01

    We propose and systematically investigate a novel tunable, compact room temperature terahertz (THz) source based on difference frequency generation in a hybrid optical and THz micro-ring resonator. We describe detailed design steps of the source capable of generating THz wave in 0.5–10 THz with a tunability resolution of 0.05 THz by using high second order optical susceptibility (χ(2)) in crystals and polymers. In order to enhance THz generation compared to bulk nonlinear material, we employ a nonlinear optical micro-ring resonator with high-Q resonant modes for infrared input waves. Another ring oscillator with the same outer radius underneath the nonlinear ring with an insulation of SiO2 layer supports the generated THz with resonant modes and out-couples them into a THz waveguide. The phase matching condition is satisfied by engineering both the optical and THz resonators with appropriate effective indices. We analytically estimate THz output power of the device by using practical values of susceptibility in available crystals and polymers. The proposed source can enable tunable, compact THz emitters, on-chip integrated spectrometers, inspire a broader use of THz sources and motivate many important potential THz applications in different fields. PMID:25800287

  8. Tunable Room Temperature THz Sources Based on Nonlinear Mixing in a Hybrid Optical and THz Micro-Ring Resonator

    NASA Astrophysics Data System (ADS)

    Sinha, Raju; Karabiyik, Mustafa; Al-Amin, Chowdhury; Vabbina, Phani K.; Güney, Durdu Ö.; Pala, Nezih

    2015-03-01

    We propose and systematically investigate a novel tunable, compact room temperature terahertz (THz) source based on difference frequency generation in a hybrid optical and THz micro-ring resonator. We describe detailed design steps of the source capable of generating THz wave in 0.5-10 THz with a tunability resolution of 0.05 THz by using high second order optical susceptibility (χ(2)) in crystals and polymers. In order to enhance THz generation compared to bulk nonlinear material, we employ a nonlinear optical micro-ring resonator with high-Q resonant modes for infrared input waves. Another ring oscillator with the same outer radius underneath the nonlinear ring with an insulation of SiO2 layer supports the generated THz with resonant modes and out-couples them into a THz waveguide. The phase matching condition is satisfied by engineering both the optical and THz resonators with appropriate effective indices. We analytically estimate THz output power of the device by using practical values of susceptibility in available crystals and polymers. The proposed source can enable tunable, compact THz emitters, on-chip integrated spectrometers, inspire a broader use of THz sources and motivate many important potential THz applications in different fields.

  9. Nonlinear distortions in silicon microring resonator filters and their impact on integrated photonic ADCs

    NASA Astrophysics Data System (ADS)

    Al Qubaisi, Kenaish; Khilo, Anatol

    2016-03-01

    We present a dynamic model based on temporal coupled-mode theory to model microring resonators considering silicon nonlinearities. By taking into account the vectorial nature of the optical modes propagating in strongly confining silicon waveguides, we introduce effective areas for two-photon absorption (TPA) and free-carrier distribution in order to adapt the rate equation describing the generation of free-carriers due to TPA and Sorefs equations for silicon waveguides. The performance of optical systems utilizing microring resonators can be degraded due to its nonlinear response. In this paper, we investigate the impact of silicon nonlinearities in microring resonators on the effective number of bits (ENOB) in integrated photonic analog-to-converters (ADCs). This is done by analyzing the nonlinear response of a first-order microring drop filter to a modulated optical pulse train. The dependence of the nonlinear response of the microring resonator, embodied in the input pulse energy vs output pulse energy, and the maximum ENOB on various filter and input pulse train parameters is analyzed by varying the finesse, microring waveguide geometry, modulation index, and average pulse energy.

  10. 3D simulation of silicon micro-ring resonator with Comsol

    NASA Astrophysics Data System (ADS)

    Degtyarev, S. A.; Podlipnov, V. V.; Verma, Payal; Khonina, S. N.

    2016-12-01

    In this paper we provide 3d full-vector static electromagnetic simulation of silicon micro-ring resonator operating. We show that geometrical and scalar approaches are not sufficiently accurate for calculating resonator parameters. Quite strong dependence of ring resonator radius on waveguide width is revealed.

  11. Photon pair generation in hydrogenated amorphous silicon microring resonators

    PubMed Central

    Hemsley, Elizabeth; Bonneau, Damien; Pelc, Jason; Beausoleil, Ray; O’Brien, Jeremy L.; Thompson, Mark G.

    2016-01-01

    We generate photon pairs in a-Si:H microrings using a CW pump, and find the Kerr coefficient of a-Si:H to be 3.73 ± 0.25 × 10−17m2/W. By measuring the Q factor with coupled power we find that the loss in the a-Si:H micro-rings scales linearly with power, and therefore cannot originate from two photon absorption. Theoretically comparing a-Si:H and c-Si micro-ring pair sources, we show that the high Kerr coefficient of this sample of a-Si:H is best utilized for microrings with Q factors below 103, but that for higher Q factor devices the photon pair rate is greatly suppressed due to the first order loss. PMID:27996014

  12. Photon pair generation in hydrogenated amorphous silicon microring resonators

    NASA Astrophysics Data System (ADS)

    Hemsley, Elizabeth; Bonneau, Damien; Pelc, Jason; Beausoleil, Ray; O’Brien, Jeremy L.; Thompson, Mark G.

    2016-12-01

    We generate photon pairs in a-Si:H microrings using a CW pump, and find the Kerr coefficient of a-Si:H to be 3.73 ± 0.25 × 10‑17m2/W. By measuring the Q factor with coupled power we find that the loss in the a-Si:H micro-rings scales linearly with power, and therefore cannot originate from two photon absorption. Theoretically comparing a-Si:H and c-Si micro-ring pair sources, we show that the high Kerr coefficient of this sample of a-Si:H is best utilized for microrings with Q factors below 103, but that for higher Q factor devices the photon pair rate is greatly suppressed due to the first order loss.

  13. Transmission performance of one waveguide and double micro-ring resonator using 3×3 optical fiber coupler

    NASA Astrophysics Data System (ADS)

    Zhao, Chao Ying; Tan, Wei Han

    2016-09-01

    This paper investigates theoretically the transmission characteristics of one waveguide and double micro-ring resonator using 3 × 3 optical fibre coupler. Our analytical solution of transmittance is suitable for either linearly distributed coupler or circularly symmetric distributed coupler. The all-optical analogue to electromagnetic inducted transparency spectrum of one waveguide and double micro-ring resonators can be controlled by changing the coupling strength between waveguide and micro-rings, the absorption coefficient around micro-rings, as well as the asymmetric coupling coefficients between non-adjacent waveguides. The curves show that the transitions of transmission spectra sensitively depend on asymmetric coupling coefficients.

  14. High Q silica microbubble resonators fabricated by arc discharge

    NASA Astrophysics Data System (ADS)

    Berneschi, S.; Farnesi, D.; Cosi, F.; Nunzi Conti, G.; Pelli, S.; Righini, G. C.; Soria, S.

    2011-09-01

    Microbubble resonators combine the unique properties of whispering gallery mode resonators with the intrinsic capability of integrated microfluidics. Here an improved fabrication method of microbubble resonators is presented, based on the heating of a slightly pressurized capillary by a rotating arc discharge. Rotation of the electrodes, moved out of a fiber splicer, ensures a homogeneous distribution of the heat all over the capillary surface. The demonstrated microbubble resonators have Q factors up to 6×107 at 1550nm. Microbubbles were filled with water and aqueous solutions of ethanol in order to test the refractive index sensing capabilities of such resonators, which also show a good temporal stability. The limit of detection of our microbubble resonator sensor is 10-6RIU.

  15. High Q silica microbubble resonators fabricated by arc discharge.

    PubMed

    Berneschi, S; Farnesi, D; Cosi, F; Conti, G Nunzi; Pelli, S; Righini, G C; Soria, S

    2011-09-01

    Microbubble resonators combine the unique properties of whispering gallery mode resonators with the intrinsic capability of integrated microfluidics. Here an improved fabrication method of microbubble resonators is presented, based on the heating of a slightly pressurized capillary by a rotating arc discharge. Rotation of the electrodes, moved out of a fiber splicer, ensures a homogeneous distribution of the heat all over the capillary surface. The demonstrated microbubble resonators have Q factors up to 6×10(7) at 1550 nm. Microbubbles were filled with water and aqueous solutions of ethanol in order to test the refractive index sensing capabilities of such resonators, which also show a good temporal stability. The limit of detection of our microbubble resonator sensor is 10(-6) RIU.

  16. Selective mode coupling in microring resonators for single mode semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Arbabi, Amir

    Single mode semiconductor laser diodes have many applications in optical communications, metrology and sensing. Edge-emitting single mode lasers commonly use distributed feedback structures, or narrowband reflectors such as distributed Bragg reflectors (DBRs) and sampled grating distributed Bragg reflectors (SGDBRs). Compact, narrowband reflectors with high reflectivities are of interest to replace the commonly used DBRs and SGDBRs. This thesis presents our work on the simulation, design, fabrication, and characterization of devices operating based on the coupling of degenerate modes of a microring resonator, and investigation of the possibility of using them for improving the performance of laser diodes. In particular, we demonstrate a new type of compact, narrowband, on-chip reflector realized by selectively coupling degenerate modes of a microring resonator. For the simulation and design of reflective microring resonators, a fast and accurate analysis method is required. Conventional numerical methods for solving Maxwell's equations such as the finite difference time domain and the finite element method (FEM) provide accurate results but are computationally intense and are not suitable for the design of large 3D structures. We formulated a set of coupled mode equations that, combined with 2D FEM simulations, can provide a fast and accurate tool for the modeling and design of reflective microrings. We developed fabrication processing recipes and fabricated passive reflective microrings on silicon substrates with a silicon nitride core and silicon dioxide cladding. Narrowband single wavelength reflectors were realized which are 70 times smaller than a conventional DBR with the same bandwidth. Compared to the conventional DBR, they have faster roll-off, and no side modes. The smaller footprint saves real estate, reduces tuning power and makes these devices attractive as in-line mirrors for low threshold narrow linewidth laser diodes. Self-heating caused by material

  17. Monolithic Cylindrical Fused Silica Resonators with High Q Factors

    PubMed Central

    Pan, Yao; Wang, Dongya; Wang, Yanyan; Liu, Jianping; Wu, Suyong; Qu, Tianliang; Yang, Kaiyong; Luo, Hui

    2016-01-01

    The cylindrical resonator gyroscope (CRG) is a typical Coriolis vibratory gyroscope whose performance is determined by the Q factor and frequency mismatch of the cylindrical resonator. Enhancing the Q factor is crucial for improving the rate sensitivity and noise performance of the CRG. In this paper, for the first time, a monolithic cylindrical fused silica resonator with a Q factor approaching 8 × 105 (ring-down time over 1 min) is reported. The resonator is made of fused silica with low internal friction and high isotropy, with a diameter of 25 mm and a center frequency of 3974.35 Hz. The structure of the resonator is first briefly introduced, and then the experimental non-contact characterization method is presented. In addition, the post-fabrication experimental procedure of Q factor improvement, including chemical and thermal treatment, is demonstrated. The Q factor improvement by both treatments is compared and the primary loss mechanism is analyzed. To the best of our knowledge, the work presented in this paper represents the highest reported Q factor for a cylindrical resonator. The proposed monolithic cylindrical fused silica resonator may enable high performance inertial sensing with standard manufacturing process and simple post-fabrication treatment. PMID:27483263

  18. Design and optimization of silicon concentric dual-microring resonators for refractive index sensing

    NASA Astrophysics Data System (ADS)

    Sun, Lei; Yuan, Jinhui; Ma, Tao; Sang, Xinzhu; Yan, Binbin; Wang, Kuiru; Yu, Chongxiu

    2017-07-01

    In this paper, a silicon concentric dual-microring resonator for refractive index sensing is designed. The influences of the mode effective index difference, extinction ratio (ER), and sensitivity on the homogeneous sensing of sucrose solutions are investigated by using 3-D finite-difference time-domain (FDTD) method. The geometry structures of the concentric dual-microring resonator are optimized to satisfy the desired sensing performance. Moreover, a refractive index sensor based on the designed concentric dual-microring resonator is proposed, which can realize the ER of 30 dB, sensitivity of 180 nm/refractive index units (RIU), and detection limit of 1.1×10-5 RIU. It is believed that the proposed refractive index sensor can find important application in the refractive index sensing.

  19. Influence of two-photon absorption on the dynamic behaviors of microring resonators.

    PubMed

    Li, Qiliang; Chen, Haowen; Xu, Jie; Hu, Miao; Zeng, Ran; Zhou, Xuefang; Li, Shuqin

    2017-04-01

    In this paper, we have investigated the influence of two-photon absorption (TPA) on the dynamic behaviors of all-pass and add-drop microring resonators by using two iterative methods along with the linear stability analysis method. While the incident field is above a certain value, the TPA coefficient has greater influence on the steady state for all-pass and add-drop microring resonators. We use the linear stability analysis method to analyze the stability of the steady state solutions and obtain stability conditions. Results obtained have shown that the change of TPA coefficient will lead to different dynamic behaviors; in addition, while the TPA coefficient is small and its change is slight, the dynamic behaviors of the microring resonators will not change much for most regions. At last, we observe the period windows and route from chaotic to period-N in some original chaotic regions due to the fluctuation of the TPA coefficient.

  20. Biomolecular Analysis with Microring Resonators: Applications in Multiplexed Diagnostics and Interaction Screening

    PubMed Central

    Kindt, Jared T.; Bailey, Ryan C.

    2013-01-01

    Silicon photonic microring resonators are a promising class of sensor whose value in bioanalytical applications has only begun to be explored. Utilized in the telecommunication industry for signal processing applications, microring resonators have more recently been re-tasked for biosensing due to their scalability, sensitivity, and versatility. Their sensing modality arises from light/matter interactions—light propagating through the microring and the resultant evanescent field extending beyond the structure is sensitive to the refractive index of the local environment, which modulates resonant wavelength of light supported by the cavity. This sensing capability has recently been utilized for the detection of numerous biological targets including proteins, nucleic acids, viruses, and small molecules. Herein we highlight some of the most exciting recent uses of this technology for biosensing applications, with an eye towards future developments in the field. PMID:23871688

  1. Photonic crystals as topological high-Q resonators.

    PubMed

    Merlin, R; Young, S M

    2014-07-28

    It is well known that defects, such as holes, inside an infinite photonic crystal can sustain localized resonant modes whose frequencies fall within a forbidden band. Here we prove that finite, defect-free photonic crystals behave as mirrorless resonant cavities for frequencies within but near the edges of an allowed band, regardless of the shape of their outer boundary. The resonant modes are extended, surface-avoiding (nearly-Dirichlet) states that may lie inside or outside the light cone. Independent of the dimensionality, quality factors and finesses are on the order of, respectively, (L/λ)3 and L/λ, where λ is the vacuum wavelength and L > λ is a typical size of the crystal. Similar topological modes exist in conventional Fabry-Pérot resonators, and in plasmonic media at frequencies just above those at which the refractive index vanishes.

  2. All-optical ultrafast XOR/XNOR logic gates, binary counter, and double-bit comparator with silicon microring resonators.

    PubMed

    Sethi, Purnima; Roy, Sukhdev

    2014-10-01

    We present designs of all-optical ultrafast YES/NOT, XOR/XNOR logic gates, binary counter, and double-bit comparator based on all-optical switching by two-photon absorption induced free-carrier injection in silicon 2 × 2 add-drop microring resonators. The proposed circuits have been theoretically analyzed using time-domain coupled-mode theory based on reported experimental values to realize low power (∼ 28 mW) ultrafast (∼ 22 ps) operation with high modulation (80%) and bit rate (45 Gb/s). The designs are complementary metal-oxide semiconductor compatible and provide advantages of high Q-factor, tunability, compactness, cascadibility, scalability, reconfigurability, simplicity, and minimal number of switches and inputs for realization of the desired logic. Although a two-bit counter has been shown, the scheme can easily be extended to N-bit counter through cascading.

  3. High-Q resonant cavities for terahertz quantum cascade lasers.

    PubMed

    Campa, A; Consolino, L; Ravaro, M; Mazzotti, D; Vitiello, M S; Bartalini, S; De Natale, P

    2015-02-09

    We report on the realization and characterization of two different designs for resonant THz cavities, based on wire-grid polarizers as input/output couplers, and injected by a continuous-wave quantum cascade laser (QCL) emitting at 2.55 THz. A comparison between the measured resonators parameters and the expected theoretical values is reported. With achieved quality factor Q ≈ 2.5 × 10(5), these cavities show resonant peaks as narrow as few MHz, comparable with the typical Doppler linewidth of THz molecular transitions and slightly broader than the free-running QCL emission spectrum. The effects of the optical feedback from one cavity to the QCL are examined by using the other cavity as a frequency reference.

  4. Hamiltonian optics formalism for microring resonator structures with varying ring resonances.

    PubMed

    Sun, Xiaolan; Yang, Zhenshan; Liu, Xiaohong; Li, Chao; Dong, Yanhua; Xie, Libin; Sipe, J E

    2011-04-11

    We develop a Hamiltonian optics formalism to quantitatively analyze a recently proposed scheme for increasing the delay-time-bandwidth product for microring resonator structures with varying ring resonances [Yang and Sipe, Opt. Lett. 32, 918 (2007)]. This theory is formally compact, simple and physically intuitive. We compare this formalism with the more rigorous transfer matrix method, and conclude that the Hamiltonian optics formalism correctly gives the average dispersion, which essentially determines the group delay as well as the dispersive distortion for pulses in the ps regime or longer.

  5. Microring resonators fabricated by electron beam bleaching of chromophore doped polymers

    SciTech Connect

    Sun Haishan; Chen Antao; Olbricht, Benjamin C.; Davies, Joshua A.; Sullivan, Philip A.; Liao Yi; Dalton, Larry R.

    2008-05-12

    Decomposition of chromophore molecules under direct electron beam irradiation reduces the refractive index of chromophore containing polymers. The induced refractive index contrast between the exposed and unexposed regions is high enough for waveguide bends of small radius and thus microring resonator devices. This electron beam bleaching of chromophore-containing polymers provides a fabrication approach for nonlinear polymer optical waveguide devices. Fabrication of high quality microring resonators with critical feature size on the order of 100 nm was demonstrated with this technique in an electro-optic polymer that contains YL124 chromophores.

  6. A simplified hollow-core microstructured optical fibre laser with microring resonators and strong radial emission

    NASA Astrophysics Data System (ADS)

    Li, Zhi-Li; Liu, Yan-Ge; Yan, Min; Zhou, Wen-Yuan; Ying, Cui-Feng; Ye, Qing; Tian, Jian-Guo

    2014-08-01

    A simplified hollow-core microstructured optical fibre (SHMOF) laser with microring resonators and strong radial emission is demonstrated. We propose that a submicron thickness silica ring embedded in the SHMOF can act as a microring resonator, with the advantages of being both compact and solid. Furthermore, the microfluidics can be easily controlled with a side pumping scheme. We also obtained a highly stable and tunable laser. The attractive possibility of developing microfluidic dye lasers within single SHMOFs presents opportunities for integrated optics applications and biomedical analysis.

  7. Analysis of Yb3+/Er3+-codoped microring resonator cross-grid matrices

    NASA Astrophysics Data System (ADS)

    Vallés, Juan A.; Gǎlǎtuş, Ramona

    2014-09-01

    An analytic model of the scattering response of a highly Yb3+/Er3+-codoped phosphate glass microring resonator matrix is considered to obtain the transfer functions of an M x N cross-grid microring resonator structure. Then a detailed model is used to calculate the pump and signal propagation, including a microscopic statistical formalism to describe the high-concentration induced energy-transfer mechanisms and passive and active features are combined to realistically simulate the performance as a wavelength-selective amplifier or laser. This analysis allows the optimization of these structures for telecom or sensing applications.

  8. Microring resonator-based optical router for photonic networks-on-chip

    NASA Astrophysics Data System (ADS)

    Zhihua, Yu; Qi, Zhang; Xin, Jin; Juan, Zhao; Hadi, Baghsiahi; Selviah, D. R.

    2016-07-01

    We report the design and analysis of a non-blocking microring resonator-based optical switched router, which can be used as a switch node to construct a large photonic routing network on chips. The proposed optical router has sixteen microrings, fourteen crossings and four 90° waveguide bends, which could be tuned through the thermo-optic (TO) or electro-optic (EO) effect. Compared with a previously described 5 × 5 optical switching router, our router comprises fewer microring resonators (MRRs), crossings and bends, which results in a more compact design, a higher switching speed, a lower loss and a lower optical power consumption. In addition, all the rings operate at the same wavelength making it scalable to a network of any size.

  9. High-Q 3D coaxial resonators for cavity QED

    NASA Astrophysics Data System (ADS)

    Yoon, Taekwan; Owens, John C.; Naik, Ravi; Lachapelle, Aman; Ma, Ruichao; Simon, Jonathan; Schuster, David I.

    Three-dimensional microwave resonators provide an alternative approach to transmission-line resonators used in most current circuit QED experiments. Their large mode volume greatly reduces the surface dielectric losses that limits the coherence of superconducting circuits, and the well-isolated and controlled cavity modes further suppress coupling to the environment. In this work, we focus on unibody 3D coaxial cavities which are only evanescently coupled and free from losses due to metal-metal interfaces, allowing us to reach extremely high quality-factors. We achieve quality-factor of up to 170 million using 4N6 Aluminum at superconducting temperatures, corresponding to an energy ringdown time of ~4ms. We extend our methods to other materials including Niobium, NbTi, and copper coated with Tin-Lead solder. These cavities can be further explored to study their properties under magnetic field or upon coupling to superconducting Josephson junction qubits, e.g. 3D transmon qubits. Such 3D cavity QED system can be used for quantum information applications, or quantum simulation in coupled cavity arrays.

  10. Ultra-High Q Acoustic Resonance in Superfluid ^4He

    NASA Astrophysics Data System (ADS)

    De Lorenzo, L. A.; Schwab, K. C.

    2017-02-01

    We report the measurement of the acoustic quality factor of a gram-scale, kilohertz-frequency superfluid resonator, detected through the parametric coupling to a superconducting niobium microwave cavity. For temperatures between 400 mK and 50 mK, we observe a T^{-4} temperature dependence of the quality factor, consistent with a 3-phonon dissipation mechanism. We observe Q factors up to 1.4× 10^8, consistent with the dissipation due to dilute ^3He impurities, and expect that significant further improvements are possible. These experiments are relevant to exploring quantum behavior and decoherence of massive macroscopic objects, the laboratory detection of continuous gravitational waves from pulsars, and the probing of possible limits to physical length scales.

  11. High-Q GaN nanowire resonators and oscillators

    SciTech Connect

    Tanner, S. M.; Gray, J. M.; Rogers, C. T.; Bertness, K. A.; Sanford, N. A.

    2007-11-12

    We report high mechanical quality factors Q for GaN nanowire cantilevers grown by molecular beam epitaxy. Nanowires with 30-500 nm diameters and 5-20 {mu}m lengths having resonance frequencies from 400 kHz to 2.8 MHz were measured. Q near room temperature and 10{sup -4} Pa ranged from 2700 to above 60 000 with most above 10 000. Positive feedback to a piezoelectric stack caused spontaneous nanowire oscillations with Q exceeding 10{sup 6}. Spontaneous oscillations also occurred with direct e-beam excitation of unintentionally doped nanowires. Doped nanowires showed no oscillations, consistent with oscillation arising via direct actuation of piezoelectric GaN.

  12. All-optical Photonic Oscillator with High-Q Whispering Gallery Mode Resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy A.; Matsko, Andrey B.; Strekalov, Dmitry; Mohageg, Makan; Iltchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We demonstrated low threshold optical photonic hyper-parametric oscillator in a high-Q 10(exp 10) CaF2 whispering gallery mode resonator which generates stable 8.5 GHz signal. The oscillations result from the resonantly enhanced four wave mixing occurring due to Kerr nonlinearity of the material.

  13. Microring and microdisk resonator-based devices for on-chip optical interconnects, particle manipulation, and biosensing

    NASA Astrophysics Data System (ADS)

    Poon, Andrew W.; Feng, Shaoqi; Cai, Hong; Lei, Ting; Chen, Hui; Luo, Xianshu

    2011-03-01

    Silicon photonics using microdisk and microring resonators are finding technologically important applications from telecommunications and on-chip optical interconnects to optofluidics and biosensing. Silicon-based microresonators that partially confine light by total internal reflection are versatile device structures which are highly wavelength-selective, reconfigurable via various refractive index tuning mechanisms, micrometer-scale footprint, and readily in/out-coupled with integrated waveguides. In this paper, we will highlight our latest progress in silicon photonics using microdisk and microring resonators for on-chip optical interconnects, optofluidics and biosensing applications including the experimental demonstrations of: (i) optical time delay and advance using silicon microring resonators integrated with pi- n diodes; (ii) photocurrent spectroscopy of microdisk resonators using two-photon-absorption induced photocarriers; (iii) optical trapping and transporting of microparticles using a water-clad silicon nitride microring resonator; and (iv) coupled microdisk resonator optical waveguide-based refractive index sensors.

  14. Optically-controlled extinction ratio and Q-factor tunable silicon microring resonators based on optical forces.

    PubMed

    Long, Yun; Wang, Jian

    2014-06-24

    Tunability is a desirable property of microring resonators to facilitate superior performance. Using light to control light, we present an alternative simple approach to tuning the extinction ratio (ER) and Q-factor of silicon microring resonators based on optical forces. We design an opto-mechanical tunable silicon microring resonator consisting of an add-drop microring resonator and a control-light-carrying waveguide ("controlling" waveguide). One of the two bus waveguides of the microring resonator is a deformable nanostring put in parallel with the "controlling" waveguide. The tuning mechanism relies on the optical force induced deflection of suspended nanostring, leading to the change of coupling coefficient of microring and resultant tuning of ER and Q-factor. Two possible geometries, i.e. double-clamped nanostring and cantilever nanostring, are studied in detail for comparison. The obtained results imply a favorable structure with the microring positioned at the end of the cantilever nanostring. It features a wide tuning range of ER from 5.6 to 39.9 dB and Q-factor from 309 to 639 as changing the control power from 0 to 1.4 mW.

  15. Optically-controlled extinction ratio and Q-factor tunable silicon microring resonators based on optical forces

    NASA Astrophysics Data System (ADS)

    Long, Yun; Wang, Jian

    2014-06-01

    Tunability is a desirable property of microring resonators to facilitate superior performance. Using light to control light, we present an alternative simple approach to tuning the extinction ratio (ER) and Q-factor of silicon microring resonators based on optical forces. We design an opto-mechanical tunable silicon microring resonator consisting of an add-drop microring resonator and a control-light-carrying waveguide (``controlling'' waveguide). One of the two bus waveguides of the microring resonator is a deformable nanostring put in parallel with the ``controlling'' waveguide. The tuning mechanism relies on the optical force induced deflection of suspended nanostring, leading to the change of coupling coefficient of microring and resultant tuning of ER and Q-factor. Two possible geometries, i.e. double-clamped nanostring and cantilever nanostring, are studied in detail for comparison. The obtained results imply a favorable structure with the microring positioned at the end of the cantilever nanostring. It features a wide tuning range of ER from 5.6 to 39.9 dB and Q-factor from 309 to 639 as changing the control power from 0 to 1.4 mW.

  16. Label-free quantitation of a cancer biomarker in complex media using silicon photonic microring resonators.

    PubMed

    Washburn, Adam L; Gunn, L Cary; Bailey, Ryan C

    2009-11-15

    Recent advances in label-free biosensing techniques have shown the potential to simplify clinical analyses. With this motivation in mind, this paper demonstrates for the first time the use of silicon-on-insulator microring optical resonator arrays for the robust and label-free detection of a clinically important protein biomarker in undiluted serum, using carcinoembryonic antigen (CEA) as the test case. We utilize an initial-slope-based quantitation method to sensitively detect CEA at clinically relevant levels and to determine the CEA concentrations of unknown samples in both buffer and undiluted fetal bovine serum. Comparison with a commercial enzyme-linked immunosorbent assay (ELISA) kit reveals that the label-free microring sensor platform has a comparable limit of detection (2 ng/mL) and superior accuracy in the measurement of CEA concentration across a 3 order of magnitude dynamic range. Notably, we report the lowest limit of detection to date for a microring resonator sensor applied to a clinically relevant cancer biomarker. Although this report describes the robust biosensing capabilities of silicon photonic microring resonator arrays for a single parameter assay, future work will focus on utilizing the platform for highly multiplexed, label-free bioanalysis.

  17. Design of a lithium niobate-on-insulator-based optical microring resonator for biosensing applications

    NASA Astrophysics Data System (ADS)

    Naznin, Shakila; Sher, Md. Sohel Mahmud

    2016-08-01

    A label-free optical microring resonator biosensor based on lithium niobate-on-insulator (LNOI) technology is designed and simulated for biosensing applications. Although silicon-on-insulator technology is quite mature over LNOI for fabricating more compact microring resonators, the latter is attractive for its excellent electro-optic, ferroelectric, piezoelectric, photoelastic, and nonlinear optic properties, which can offer a wide range of tuning facilities for sensing. To satisfy the requirement of high sensitivity in biosensing, the dual-microring resonator model is applied to design the proposed sensor. The transmission spectrum obtained from two-dimensional simulations based on finite-difference time-domain method demonstrates that the designed LNOI microring sensor consisting of a 10-μm outer ring and a 5-μm inner ring offers a sensitivity of ˜68 nm/refractive index unit (RIU) and a minimum detection limit of 10-2 RIU. Finally, the sensor's performance is simulated for glucose sensing, a biosensing application.

  18. High-Q plasmonic infrared absorber for sensing of molecular resonances in hybrid lead halide perovskites

    NASA Astrophysics Data System (ADS)

    Dayal, Govind; Solanki, Ankur; Yu Chin, Xin; Sum, Tze Chien; Soci, Cesare; Singh, Ranjan

    2017-08-01

    Plasmonic resonances in sub-wavelength metal-dielectric-metal cavities have been shown to exhibit strong optical field enhancement. The large field enhancements that occur in sub-wavelength regions of the cavity can drastically boost the performance of microcavity based detectors, electromagnetic wave absorbers, metasurface hologram, and nonlinear response of the material in a cavity. The performance efficiencies of these plasmonic devices can be further improved by designing tunable narrow-band high-Q cavities. Here, we experimentally and numerically demonstrate high-Q resonances in metal-dielectric-metal cavity consisting of an array of conductively coupled annular and rectangular apertures separated from the bottom continuous metal film by a thin dielectric spacer. Both, the in-plane and out of plane coupling between the resonators and the continuous metal film have been shown to support fundamental and higher order plasmonic resonances which result in high-Q response at mid-infrared frequencies. As a sensor application of the high-Q cavity, we sense the vibrational resonances of an ultrathin layer of solution-processed organic-inorganic hybrid lead halide perovskites.

  19. High-order micro-ring resonator with perfect transmission using symmetrical Fibonacci structures.

    PubMed

    Tsao, C W; Cheng, Y H; Hsueh, W J

    2015-09-15

    A symmetrical Fibonacci micro-ring resonator (SFMR) has been presented to avoid the coupled resonator optical waveguide (CROW) bottle, which is a bottle-shaped distribution for high orders in transmission spectra. The SFMR features three advantages that improve filtering quality compared to that provided by traditional periodic micro-ring resonators. First, sharper resonances are obtained by eliminating the CROW bottle from the mini gaps that appear in the major-band region. Second, peaks with perfect transmission are always obtained without a radius and coupling modulation in the mini-band regions and major-band regions. Third, the full width at half-maximum of the band-edge peak decreases with the increasing generation order.

  20. Conversion between EIT and Fano spectra in a microring-Bragg grating coupled-resonator system

    NASA Astrophysics Data System (ADS)

    Zhang, Zecen; Ng, Geok Ing; Hu, Ting; Qiu, Haodong; Guo, Xin; Wang, Wanjun; Rouifed, Mohamed Saïd; Liu, Chongyang; Wang, Hong

    2017-08-01

    A conversion between the electromagnetically induced transparency (EIT) transmission and Fano transmission is theoretically and experimentally demonstrated in an all-pass microring-Bragg grating (APMR-BG) coupled-resonator system. In this work, the coupling between the two resonators (the microring resonator and the Fabry-Perot resonator formed by two Bragg gratings) gives rise to the EIT and Fano transmissions. The resonant status strongly depends on the round-trip attenuation of the microring and the coupling strength. By tuning the coupling strength, the EIT and Fano transmissions can be controlled and converted. The device performance has been theoretically calculated and analyzed with a specially developed numerical model based on the transfer matrix method. The APMR-BG coupled-resonator systems with different gap widths were designed, fabricated, and characterized on a silicon-on-insulator (SOI) platform. The conversion of resonance was experimentally observed and verified. In addition, this on-chip system has the advantage of a small footprint, and the fabrication process is compatible with the planar waveguide fabrication process.

  1. Guided mode resonance with extremely high Q-factors in terahertz metamaterials

    NASA Astrophysics Data System (ADS)

    Chen, Hang; Liu, Jianjun; Hong, Zhi

    2017-01-01

    We proposed and demonstrated that guided mode resonance (GMR) response with extremely high quality factor can be achieved in a planar terahertz metamaterial (MM) by rotating split ring resonators (SRRs) or moving the gaps of SRRs in a two-SRR composed MM. Furthermore, a novel extremely sharp asymmetric Fano resonance or electromagnetically induced transparency (EIT) like spectral response can be easily realized by manipulating the coherent interaction between this high Q GMR and the dipole resonance of MM. The new method can be extended to other ranges of the electromagnetic spectrum, and open new horizons for the design of ultra-high Q metamaterials for multifunctional applications, such as ultra-sensitive sensors, narrowband filters, or slow light based devices.

  2. Low-loss and high index-contrast tantalum pentoxide microring resonators and grating couplers on silicon substrates.

    PubMed

    Rabiei, Payam; Rao, Ashutosh; Chiles, Jeff; Ma, Jichi; Fathpour, Sasan

    2014-09-15

    A platform for high index-contrast integrated photonics based on tantalum pentoxide submicrometer waveguides on silicon substrates is introduced. The platform allows demonstration of microring resonators with loaded quality factor, Q, of 67,000 and waveguides with a propagation loss of 4.9 dB/cm. Grating couplers, with an insertion loss of ~6 dB per coupler and 3 dB bandwidth of ~50 nm, are also demonstrated and integrated with microring resonators.

  3. Optimized design of high-order series coupler Yb3+/Er3+ codoped phosphate glass microring resonator filters

    NASA Astrophysics Data System (ADS)

    Galatus, Ramona; Valles, Juan

    2016-04-01

    The optimized geometry based on high-order active microring resonators (MRR) geometry is proposed. The solution possesses both the filtering and amplifying functions for the signal at around 1534nm (pump 976 nm). The cross-grid resonator with laterally, series-coupled triple-microrings, having 15.35μm radius, in a co-propagation topology between signal and pump, is the structure under analysis (commonly termed an add-drop filter).

  4. Droplet sensing using small and compact high-Q planar resonator based on impedance matching technique.

    PubMed

    Lee, Hee-Jo; Yook, Jong-Gwan

    2016-09-01

    In this paper, we demonstrate the sensing feasibility of the proposed high-Q resonator using a phosphate-buffered saline droplet at microwave frequencies. In the experimental results, the resonant frequency, signal level, and Q-factor of the S21-parameter with and without a 1-μl droplet were changed to about 230 MHz, 32 dB, and 1500, respectively. The resonator system was found to be suitable for droplet sensing with a small volume due to its small and compact scheme. This resonator system is expected to play an important role in droplet sensing with different dielectric constants.

  5. Droplet sensing using small and compact high-Q planar resonator based on impedance matching technique

    NASA Astrophysics Data System (ADS)

    Lee, Hee-Jo; Yook, Jong-Gwan

    2016-09-01

    In this paper, we demonstrate the sensing feasibility of the proposed high-Q resonator using a phosphate-buffered saline droplet at microwave frequencies. In the experimental results, the resonant frequency, signal level, and Q-factor of the S21-parameter with and without a 1-μl droplet were changed to about 230 MHz, 32 dB, and 1500, respectively. The resonator system was found to be suitable for droplet sensing with a small volume due to its small and compact scheme. This resonator system is expected to play an important role in droplet sensing with different dielectric constants.

  6. High quality factor trapezoidal subwavelength grating waveguide micro-ring resonator

    NASA Astrophysics Data System (ADS)

    Wang, Zheng; Xu, Xiaochuan; Fan, D. L.; Wang, Yaguo; Chen, Ray T.

    2016-03-01

    In recent decades, silicon photonics has attracted intensive research interest in optical communications due to its advantageous compact dimensions and high-volume manufacturability. Particularly, micro-ring resonators on silicon-oninsulator (SOI) platform have been widely exploited as a basic building block for a vast range of applications such as switches, modulators, and sensors. A majority of these applications involve light-matter interaction, which can be substantially enhanced by the high quality factor micro-ring resonators. However, conventional strip waveguide based micro-ring resonators suffer from the intrinsic dilemma in achieving high light confinement and strong light-matter interaction simultaneously. Subwavelength grating (SWG) waveguides, comprised of periodically interleaved high and low refractive index materials with a pitch less than one wavelength, have been demonstrated as a promising alternative. For SWG waveguides built on SOI wafers, the ratio of silicon and cladding materials can be engineered microscopically to achieve desired macroscopic properties. The control of these properties could potentially lead to significant performance improvements compared with conventional micro-ring resonators based photonic devices, such as filters and sensors. However, SWG waveguide based micro-ring resonators (SWGMRs) that have been demonstrated so far can only provide a moderate quality factor (~5600) with a large radius (e.g. 15 μm), which greatly jeopardize the wide spread research efforts in this area. In this paper, we propose to use trapezoidal silicon pillars to reduce the bend loss of SWGMRs to improve the quality factor. For the first time, we experimentally demonstrate the smallest SWGMR (the micro-ring radius equals to 5 μm) with an applicable quality factor as high as 11,500. This approach also can be applied to SWGMRs with larger radii for higher quality factors. We also experimentally demonstrated a 10 μm radius SWGMR that can provide

  7. Continuously tunable photonic fractional Hilbert transformer using a high-contrast germanium-doped silica-on-silicon microring resonator.

    PubMed

    Shahoei, Hiva; Dumais, Patrick; Yao, Jianping

    2014-05-01

    We propose and experimentally demonstrate a continuously tunable fractional Hilbert transformer (FHT) based on a high-contrast germanium-doped silica-on-silicon (SOS) microring resonator (MRR). The propagation loss of a high-contrast germanium-doped SOS waveguide can be very small (0.02 dB/cm) while the lossless bend radius can be less than 1 mm. These characteristics lead to the fabrication of an MRR with a high Q-factor and a large free-spectral range (FSR), which is needed to implement a Hilbert transformer (HT). The SOS MRR is strongly polarization dependent. By changing the polarization direction of the input signal, the phase shift introduced at the center of the resonance spectrum is changed. The tunable phase shift at the resonance wavelength can be used to implement a tunable FHT. A germanium-doped SOS MRR with a high-index contrast of 3.8% is fabricated. The use of the fabricated MRR for the implementation of a tunable FHT with tunable orders at 1, 0.85, 0.95, 1.05, and 1.13 for a Gaussian pulse with the temporal full width at half-maximum of 80 ps is experimentally demonstrated.

  8. Bandwidth-limited control and ringdown suppression in high-Q resonators.

    PubMed

    Borneman, Troy W; Cory, David G

    2012-12-01

    We describe how the transient behavior of a tuned and matched resonator circuit and a ringdown suppression pulse may be integrated into an optimal control theory (OCT) pulse-design algorithm to derive control sequences with limited ringdown that perform a desired quantum operation in the presence of resonator distortions of the ideal waveform. Inclusion of ringdown suppression in numerical pulse optimizations significantly reduces spectrometer deadtime when using high quality factor (high-Q) resonators, leading to increased signal-to-noise ratio (SNR) and sensitivity of inductive measurements. To demonstrate the method, we experimentally measure the free-induction decay of an inhomogeneously broadened solid-state free radical spin system at high Q. The measurement is enabled by using a numerically optimized bandwidth-limited OCT pulse, including ringdown suppression, robust to variations in static and microwave field strengths. We also discuss the applications of pulse design in high-Q resonators to universal control of anisotropic-hyperfine coupled electron-nuclear spin systems via electron-only modulation even when the bandwidth of the resonator is significantly smaller than the hyperfine coupling strength. These results demonstrate how limitations imposed by linear response theory may be vastly exceeded when using a sufficiently accurate system model to optimize pulses of high complexity. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Novel ultrasound detector based on small slot micro-ring resonator with ultrahigh Q factor

    NASA Astrophysics Data System (ADS)

    Zhang, Senlin; Chen, Jian; He, Sailing

    2017-01-01

    An ultrasound detector based on a novel slot micro-ring resonator (SMRR) with ultrahigh Q factor and small size is proposed in this study. The theoretical Q factor of SMRR can be approximately 8.34×108 with bending radius of merely 12 μm. The ultrahigh Q factor leads to an enhanced sensitivity that is approximately two orders of that of state-of-the-art ultrasound detector based on polymer micro-ring resonator. Moreover, the 3 dB bandwidth of the ultrasound detector is approximately 540 MHz, thereby leading to an ultrahigh axial resolution of 1.2 μm. The proposed detector is also CMOS compatible and can be easily and extensively integrated to be maximized in photoacoustic microscopy.

  10. Highly sensitive optical biosensor based on silicon-microring-resonator-loaded Mach-Zehnder interferometer

    NASA Astrophysics Data System (ADS)

    Yoshida, Soichiro; Ishihara, Shintaro; Arakawa, Taro; Kokubun, Yasuo

    2017-04-01

    We propose and demonstrate a novel biosensor based on a silicon-single-microring-resonator-loaded Mach-Zehnder interferometer (MRR-MZI), and discuss the design of the sensor theoretically. Owing to the combination of an MZI and the enhanced phase change in a microring resonator (MRR), high sensitivity is expected to be realized. The designed MRR-MZI sensor is fabricated using a CMOS-compatible process, and its sensing characteristics are measured using ethanol solutions with a concentration of less than 3 wt % and avidin solutions. The sensitivity of the MRR-MZI to changes in the environmental refractive index is increased by approximately 50 times compared with that of a simple MRR. In addition, avidin solution with a concentration as low as 20 pM was successfully detected.

  11. Submicron optical waveguides and microring resonators fabricated by selective oxidation of tantalum.

    PubMed

    Rabiei, Payam; Ma, Jichi; Khan, Saeed; Chiles, Jeff; Fathpour, Sasan

    2013-03-25

    Submicron tantalum pentoxide ridge and channel optical waveguides and microring resonators are demonstrated on silicon substrates by selective oxidation of the refractory metal, tantalum. The novel method eliminates the surface roughness problem normally introduced during dry etching of waveguide sidewalls and also simplifies fabrication of directional couplers. It is shown that the measured propagation loss is independent of the waveguide structure and thereby limited by the material loss of tantalum pentoxide in waveguides core regions. The achieved microring resonators have cross-sectional dimensions of ~600 nm × ~500 nm, diameters as small as 80 µm with a quality, Q, factor of 4.5 × 10(4), and a finesse of 120.

  12. Design and optimization of optical modulators based on graphene-on-silicon nitride microring resonators

    NASA Astrophysics Data System (ADS)

    Wu, Zeru; Chen, Yujie; Zhang, Tianyou; Shao, Zengkai; Wen, Yuanhui; Xu, Pengfei; Zhang, Yanfeng; Yu, Siyuan

    2017-04-01

    In order to overcome the challenge of obtaining high modulation depth due to weak graphene–light interaction, a graphene-on-silicon nitride (SiNx) microring resonator based on graphene’s gate-tunable optical conductivity is proposed and studied. Geometrical parameters of graphene-on-SiNx waveguide are systematically analyzed and optimized, yielding a loss tunability of 0.04 dB μm‑1 and an effective index variation of 0.0022. We explicitly study the interaction between graphene and a 40 μm-radius microring resonator, where electro-absorptive and electro-refractive modulation are both taken into account. By choosing appropriate graphene coverage and coupling coefficient, a high modulation depth of over 40 dB with large fabrication tolerance is obtained.

  13. Label-free biosensor based on an electrical tracing-assisted silicon microring resonator with a low-cost broadband source.

    PubMed

    Kim, Kyung Woo; Song, Junfeng; Kee, Jack Sheng; Liu, Qing; Lo, Guo-Qiang; Park, Mi Kyoung

    2013-08-15

    We present a novel biosensor based on an electrical tracing-assisted silicon dual-microring resonator sensor system. The dual-microring system comprises one microring resonator as a sensing element and the other microring resonator integrated with an electrical controller as a tracing element. The resonance wavelength shift of the sensing microring induced by the refractive index change due to antigen-ligand bindings is traced and determined by direct voltage applied to the electrical tunable tracing microring. The sensor system enables the use of a low-cost broadband light source instead of a bulky and expensive tunable laser, which allows the development of cost-effective point-of-care diagnostic devices by significantly reducing the device cost and increasing its portability. The sensing capability of the developed dual-microring sensor was investigated using biotin-streptavidin binding as a model system. We have demonstrated the quantitative detection of streptavidin over a broad range of concentrations down to 190 pM by monitoring the electrical power applied to the tracing ring. We have also validated the sensing principle of the dual-microring system by a direct comparison between the calculated and measured values for the resonance wavelength shift of the sensing microring. Furthermore, we have shown the quantitative and specific detection of a well-known breast cancer biomarker, human epidermal growth factor receptor 2 (HER2), in a bovine serum albumin solution using the antibody-modified dual-microring sensor system.

  14. Microfluidics-integrated cascaded double-microring resonators for label-free biosensing

    NASA Astrophysics Data System (ADS)

    Chen, Yangqing; Yu, Fang; Yang, Chang; Li, Mingyu; Tang, Longhua; Song, Jinyan; He, Jian-Jun

    2014-11-01

    A highly-sensitive optical waveguide biosensor integrated with microfluidic channels based on silicon-on-insulator (SOI) was investigated in this paper. Experimental results of the label-free detection exhibits this novel biosensor with the superior reliability for quantitative and kinetic measurement of the interaction between biological molecules, dramatically improving the sensitivity due to the Vernier effect induced by cascaded double-microring resonators.

  15. Photoacoustic probe using a micro-ring resonator ultrasonic sensor for endoscopic applications

    PubMed Central

    Dong, Biqin; Chen, Siyu; Zhang, Zhen; Sun, Cheng; Zhang, Hao F.

    2015-01-01

    We designed an all-optical photoacoustic probe for endoscopic applications by employing an optically-transparent, coverslip-type, polymeric micro-ring resonator ultrasonic sensor. We experimentally quantified the axial, tangential, and radial resolutions and angular sensitive stability of this probe. Using this probe, we achieved volumetric imaging of several phantoms. Our all-optical probe design offers clear benefit in integrating photoacoustic endoscope with other optical endoscopic imaging modalities to facilitate the transformation from bench to bedside. PMID:25078180

  16. Label-free, single-object sensing with a microring resonator: FDTD simulation.

    PubMed

    Nguyen, Dan T; Norwood, Robert A

    2013-01-14

    Label-free, single-object sensing with a microring resonator is investigated numerically using the finite difference time-domain (FDTD) method. A pulse with ultra-wide bandwidth that spans over several resonant modes of the ring and of the sensing object is used for simulation, enabling a single-shot simulation of the microring sensing. The FDTD simulation not only can describe the circulation of the light in a whispering-gallery-mode (WGM) microring and multiple interactions between the light and the sensing object, but also other important factors of the sensing system, such as scattering and radiation losses. The FDTD results show that the simulation can yield a resonant shift of the WGM cavity modes. Furthermore, it can also extract eigenmodes of the sensing object, and therefore information from deep inside the object. The simulation method is not only suitable for a single object (single molecule, nano-, micro-scale particle) but can be extended to the problem of multiple objects as well.

  17. A Highly Sensitive Refractometric Sensor Based on Cascaded SiN Microring Resonators

    PubMed Central

    Zamora, Vanessa; Lützow, Peter; Weiland, Martin; Pergande, Daniel

    2013-01-01

    We investigate a highly sensitive optical sensor based on two cascaded microring resonators exploiting the Vernier effect. The architecture consists of two microrings with a slight difference in their free spectral ranges. This allows the generation of the Vernier effect for achieving ultra-high sensitivities. The sensor chip was fabricated using a silicon nitride platform and characterized with isopropanol/ethanol mixtures. A sensitivity of 0.95 nm/% was found for isopropanol concentrations in ethanol ranging from 0% to 10%. Furthermore, a collection of measurements was carried out using aqueous sodium chloride (NaCl) in solutions of different concentrations, confirming a high sensitivity of 10.3 nm/% and a bulk refractive index sensitivity of 6,317 nm/RIU. A limit of detection of 3.16 × 10−6 RIU was determined. These preliminary results show the potential features of cascaded silicon nitride microring resonators for real-time and free-label monitoring of biomolecules for a broad range of applications. PMID:24169543

  18. Single domain antibodies for the detection of ricin using silicon photonic microring resonator arrays.

    PubMed

    Shia, Winnie W; Bailey, Ryan C

    2013-01-15

    Ricin is a lethal protein toxin derived from the castor bean plant. Given its notorious history as a biowarfare agent and homicidal weapon, ricin has been classified as a category B bioterrorism agent. Current ricin detection methods based on immunoassays lack the required sensitivity and specificity for many homeland security surveillance applications. Importantly, many conventional antibody-based methodologies are unable to distinguish ricin from RCA 120, a nontoxic protein also found in the castor bean plant. Single domain antibodies (sdAbs), which are recombinantly derived from immunized llamas, are known to have high affinities for ricin A or B chains and low cross-reactivity with RCA 120. Herein, we demonstrate the use of silicon photonic microring resonators for antibody affinity profiling and one-step ricin detection at concentrations down to 300 pM using a 15 min, label-free assay format. These sdAbs were also simultaneously compared with a commercial anti-RCA IgG antibody in a multicapture agent, single target immunoassay using arrays of microrings, which allowed direct comparison of sensitivity and specificity. A selected sdAb was also found to exhibit outstanding specificity against another biotoxin, saporin, which has mechanism of action similar to ricin. Given the rapidity, scalability, and multiplexing capability of this silicon-based technology, this work represents a step toward using microring resonator arrays for the sensitive and specific detection of biowarfare agents.

  19. Optimized design of Yb3+/Er3+-codoped cross-coupled integrated microring resonator arrays

    NASA Astrophysics Data System (ADS)

    Gǎlǎtus, Ramona; Vallés, Juan A.

    2014-09-01

    In this work the analytical model of the scattering response of a highly Yb3+/Er3+-codoped phosphate glass microring resonator array is developed. The microscopic statistical formalism is used to simulate its performance as a wavelengthselective amplifier. The performance of the integrated add-drop filter was investigated based on the signal transfer functions for Through and Drop ports, correlated the with gain coefficient and its dependence on pump power, signal power and Yb3+/Er3+- dopants concentration. In consequence, microring arrays with gain operating in the near infrared spectral range and, in particular, in the 1.5-mm wavelength band (emission band of Er-doped fiber amplifiers and lasers, already used in several bio/chemical sensing tasks) are highly attractive.

  20. Stimulated Brillouin laser and frequency comb generation in high-Q microbubble resonators.

    PubMed

    Lu, Qijing; Liu, Sheng; Wu, Xiang; Liu, Liying; Xu, Lei

    2016-04-15

    We report on the stimulated Brillouin laser (SBL) and over-dense frequency comb generation in high-Q microbubble resonators (MBRs). Both first-order and cascaded SBL are achieved due to the rich high-order axial modes in the MBRs, although the free spectral range (FSR) of azimuthal mode of the MBR is severely mismatched with the Brillouin shift. The SBL is also generated by varying the internal pressure of MBR at fixed initially non-resonant pump light wavelength. In addition, over-dense frequency combs are realized with comb spacings that are one and two FSRs of aixal mode.

  1. Low power and compact reconfigurable multiplexing devices based on silicon microring resonators.

    PubMed

    Dong, Po; Qian, Wei; Liang, Hong; Shafiiha, Roshanak; Feng, Ning-Ning; Feng, Dazeng; Zheng, Xuezhe; Krishnamoorthy, Ashok V; Asghari, Mehdi

    2010-05-10

    We present thermally reconfigurable multiplexing devices based on silicon microring resonators with low tuning power and low thermal crosstalk. Micro-heaters on top of the rings are employed to tune the resonant wavelengths through the thermo-optic effect of silicon. We achieve a low tuning power of 21 mW per free spectral range for a single ring by exploiting thermal isolation trenches close to the ring waveguides. Negligible thermal crosstalk is demonstrated for rings spaced by 15 microm, enabling compact multiplexing devices. The tuning time constant is demonstrated to be less than 10 micros.

  2. Ultra-flat and broad optical frequency combs generation based on novel dispersion-flattened double-slot microring resonator

    NASA Astrophysics Data System (ADS)

    Wang, Yuanwu; Zhang, Minming; Lu, Luluzi; Li, Meifeng; Wang, Jinghao; Zhou, Feiya; Dai, Jing; Deng, Lei; Liu, Deming

    2016-01-01

    In this paper, a novel double-slot microring resonator is proposed to produce flat dispersion of 0-3.8 ps/(nm km) over 1150 nm wavelength range. Moreover, the dispersion tailoring with different structural parameters of the proposed microring resonator is analyzed and simulated. The simulation results show that the dispersion fluctuation can be tailored by the height of the central and bottom As2S3 layer, and the slope can be adjusted by the waveguide width and lower SiO2 slot thickness. Furthermore, by means of the Lugiato-Lefever equation, an ultra-flat and broad optical frequency comb with 7-dB bandwidth of 1155 nm (1855-3010 nm) is obtained based on such dispersion-optimized resonator. The proposed double-slot microring resonator shows potential application in both telecommunication and mid-infrared research domain.

  3. High-Q AlN Contour Mode Resonators with Unattached, Voltage-Actuated Electrodes

    NASA Astrophysics Data System (ADS)

    Schneider, Robert Anthony

    High-Q narrowband filters at ultra-high frequencies hold promise for reducing noise and suppressing interferers in wireless transceivers, yet research efforts confront a daunting challenge. So far, no existing resonator technology can provide the simultaneous high-Q, high electromechanical coupling ( k2eff), frequency tunability, low motional resistance (Rx), stopband rejection, self-switchability, frequency accuracy, and power handling desired to select individual channels or small portions of a band over a wide RF range. Indeed, each technology provides only a subset of the desired properties. Recently introduced "capacitive-piezoelectric" resonators, i.e., piezoelectric resonators with non-contacting transduction electrodes, known for achieving very good Q's, have recently emerged (in the early 2010's) as a contender among existing technologies to address the needs of RF narrowband selection. Several reports of such devices, made from aluminum nitride (AlN), have demonstrated improved Q's over attached electrode counterparts at frequencies up to 1.2 GHz, albeit with reduced transduction efficiency due to the added capacitive gaps. Fabrication challenges, while still allowing for a glimpse of the promise of this technology, have, until now, hindered attempts at more complex devices than just simple resonators with improved Q's. This thesis project demonstrates several key improvements to capacitive-piezo technology, which, taken together, further bolster its case for deployment for frequency control applications. (Abstract shortened by ProQuest.).

  4. Applications of optical micro-ring and micro-disk resonators as physical, chemical, and biological sensors

    NASA Astrophysics Data System (ADS)

    Bhola, Bipin

    This dissertation presents the applications of optical micro-ring and micro-disk resonators as various sensors in physical, chemical, and biological applications. This work describes the functioning of 5 different sensors and suggests ways for optimizing the performance of each of them. All of these sensors work on the principle of shift in the resonance wavelength of the micro-ring or the micro-disk in response to an external physical, chemical or biological perturbation. The first portion describes the functioning of a ring resonator device and details the various parameters which are important in sensing applications. Then a strain sensor, an accelerometer, and a humidity sensor based on polymer micro-ring resonator are described. The strain sensor has a sensitivity of 0.32pm/muε and a dynamic range of 17000muε, the accelerometer has a sensitivity of 31pm/g and a dynamic range of +/-7g, whereas, the humidity sensor has a sensitivity of 16pm/%RH and a dynamic range of 72%. The dependency of each of their sensitivities and dynamic ranges on various geometrical parameters are also discussed. The response time of the humidity sensor was reduced to less than 200ms which enables us to utilize this device as a human breathing monitor in hospitals. The second portion of the thesis, discusses the possible incorporation of ultra-high-Q silica micro-disk resonators, developed at the Jet Propulsion Laboratory by Mr. Thanh M. Le, into various sensing devices. This device is first proposed as a biosensor for detecting trace amounts of specific biomolecules. The first experiments are performed for developing the silica micro-disk as a biosensor. In this experiment, the sensitivity of the micro-disk as a function of change in refractive index of the surrounding medium is demonstrated. The observed sensitivity is 11.82nm/RIU (Refractive Index Units). Then, the possibility of using this device as a specific biosensor is explored. The method for surface functionalization of the

  5. High-Q lattice mode matched structural resonances in terahertz metasurfaces

    SciTech Connect

    Xu, Ningning; Zhang, Weili; Singh, Ranjan

    2016-07-11

    The quality (Q) factor of metamaterial resonances is limited by the radiative and non-radiative losses. At terahertz frequencies, the dominant loss channel is radiative in nature since the non-radiative losses are low due to high conductivity of metals. Radiative losses could be suppressed by engineering the meta-atom structure. However, such suppression usually occurs at the fundamental resonance mode which is typically a closed mode resonance such as an inductive-capacitive resonance or a Fano resonance. Here, we report an order of magnitude enhancement in Q factor of all the structural eigenresonances of a split-ring resonator fueled by the lattice mode matching. We match the fundamental order diffractive mode to each of the odd and even eigenresonances, thus leading to a tremendous line-narrowing of all the resonances. Such precise tailoring and control of the structural resonances in a metasurface lattice could have potential applications in low-loss devices, sensing, and design of high-Q metamaterial cavities.

  6. Laser-machined ultra-high-Q microrod resonators for nonlinear optics

    NASA Astrophysics Data System (ADS)

    Del'Haye, Pascal; Diddams, Scott A.; Papp, Scott B.

    2013-06-01

    Optical whispering-gallery microresonators are useful tools in microphotonics and non-linear optics at very low threshold powers. Here, we present details about the fabrication of ultra-high-Q whispering-gallery-mode resonators made by CO2-laser lathe machining of fused-quartz rods. The resonators can be fabricated in less than 1 min and the obtained optical quality factors exceed Q = 1 × 109. Demonstrated resonator diameters are in the range between 170 μm and 8 mm (free spectral ranges between 390 GHz and 8 GHz). Using these microresonators, a variety of optical nonlinearities are observed, including Raman scattering, Brillouin scattering, and four-wave mixing.

  7. Coupling Light from a High-Q Microsphere Resonator Using a UV-induced Surface Grating

    NASA Technical Reports Server (NTRS)

    Ilchenko, V. S.; Starodubov, D. S.; Gorodetsky, M. L.; Maleki, L.; Feinberg, J.

    2000-01-01

    High-Q microspheres with whispering-gallery modes have very narrow resonances that can be used for fiber-optic filters, ultra-compact narrow-linewidth lasers and optical/microwave oscillators. Whispering-gallery modes were previously excited in microspheres using evanescent optical fields. The necessary phase synchronism was obtained by adjusting the incident angle of input light beam (prism coupler) or adjustment of the waveguide propagation constant (fiber taper coupler). For many applications, however, bulky near-field couplers are undesirable. They compromise the symmetry and generate stray fields. Also, the control of coupling is crucial for the performance of microsphere resonators: in analogy with radio frequency circuits, the loading Q-factor should be less than the intrinsic Q-factor, Q(sub L) less than or equal to Q(sub O). Ideally one should combine a stable coupling element and a resonator into a single microsphere component.

  8. Enhancing the resonance stability of a high-Q micro/nanoresonator by an optical means

    NASA Astrophysics Data System (ADS)

    Sun, Xuan; Luo, Rui; Zhang, Xi-Cheng; Lin, Qiang

    2016-02-01

    High-quality optical resonators underlie many important applications ranging from optical frequency metrology, precision measurement, nonlinear/quantum photonics, to diverse sensing such as detecting single biomolecule, electromagnetic field, mechanical acceleration/rotation, among many others. All these applications rely essentially on the stability of optical resonances, which, however, is ultimately limited by the fundamental thermal fluctuations of the devices. The resulting thermo-refractive and thermo-elastic noises have been widely accepted for nearly two decades as the fundamental thermodynamic limit of an optical resonator, limiting its resonance uncertainty to a magnitude 10-12 at room temperature. Here we report a novel approach that is able to significantly improve the resonance stability of an optical resonator. We show that, in contrast to the common belief, the fundamental temperature fluctuations of a high-Q micro/nanoresonator can be suppressed remarkably by pure optical means without cooling the device temperature, which we term as temperature squeezing. An optical wave with only a fairly moderate power launched into the device is able to produce strong photothermal backaction that dramatically suppresses the spectral intensity of temperature fluctuations by five orders of magnitudes and squeezes the overall level (root-mean-square value) of temperature fluctuations by two orders of magnitude. The proposed approach is universally applicable to various micro/nanoresonator platforms and the optimal temperature squeezing can be achieved with an optical Q around 106-107 that is readily available in various current devices. The proposed photothermal temperature squeezing is expected to have profound impact on broad applications of high-Q cavities in sensing, metrology, and integrated nonlinear/quantum photonics.

  9. [Study on Strain Detection with Si Based on Bicyclic Cascade Optical Microring Resonator].

    PubMed

    Tang, Jun; Lei, Long-hai; Zhang, Wei; Zhang, Tian-en; Xue, Chen-yang; Zhang, Wen-dong; Liu, Jun

    2016-03-01

    Optical micro-ring resonator prepared on Silicon-On-Insulator (SOI) has high sensitivity, small size and low mode volume. Its high sensitivity has been widely applied to the optical information transmission and inertial navigation devices field, while it is rarely applied in the testing of Mechanics. This paper presents a cantilever stress/strain gauge with an optical microring resonator. It is proposed the using of radius change of ring waveguide for the sensing element. When external stress is put on the structure, the radius of the SOI ring waveguide will be subjected to variation, which causes the optical resonant parameters to change. This ultimately leads to a red-shift of resonant spectrum, and shows the excellent characteristics of the structure's stress/strain sensitivity. Designed a bicyclic cascade embedded optical micro-cavity structure, which was prepared by employing MEMS lithography and ICP etching process. The characteristic of stress/strain sensitivity was calculated theoretically. Two values of 0.185 pm x kPa(-1) and 18.04 pm x microstrain(-1) were obtained experimentally, which also was verified by theoretical simulations. Comparing with the single-loop micro-cavity structure, its measuring range and stress sensitivity increased by nearly 50.3%, 10.6%, respectively. This paper provides a new method to develop micro-opto-electromechanical system (MOEMS) sensors.

  10. Tunable complex-valued multi-tap microwave photonic filter based on single silicon-on-insulator microring resonator.

    PubMed

    Lloret, Juan; Sancho, Juan; Pu, Minhao; Gasulla, Ivana; Yvind, Kresten; Sales, Salvador; Capmany, José

    2011-06-20

    A complex-valued multi-tap tunable microwave photonic filter based on single silicon-on-insulator microring resonator is presented. The degree of tunability of the approach involving two, three and four taps is theoretical and experimentally characterized, respectively. The constraints of exploiting the optical phase transfer function of a microring resonator aiming at implementing complex-valued multi-tap filtering schemes are also reported. The trade-off between the degree of tunability without changing the free spectral range and the number of taps is studied in-depth. Different window based scenarios are evaluated for improving the filter performance in terms of the side-lobe level.

  11. Label-free biosensing using cascaded double-microring resonators integrated with microfluidic channels

    NASA Astrophysics Data System (ADS)

    Chen, Yangqing; Yu, Fang; Yang, Chang; Song, Jinyan; Tang, Longhua; Li, Mingyu; He, Jian-Jun

    2015-06-01

    Fast and accurate quantitative measurement of biologically relevant molecules has been demonstrated for medical diagnostics and drug applications in photonic integrated circuits. Herein, we reported a highly-sensitive optical biosensor based on cascaded double-microring resonators. The sensor was integrated with microfluidic channels and investigated with its label-free detection capability. With a wavelength resolution of 0.47 nm, the measured binding capacity of the antibody on the surface exhibits reliable detection limit down to 7.10 μg/mL using human immunoglobulin G (hIgG).

  12. Reconfigurable non-blocking four-port optical router based on microring resonators.

    PubMed

    Yang, Lin; Jia, Hao; Zhao, Yunchou; Chen, Qiaoshan

    2015-03-15

    A reconfigurable non-blocking four-port optical router with the least optical switches is demonstrated. The device is based on microring resonators tuned through thermo-optic effect. The optical signal-to-noise ratio of the device at its nine routing states is about 15 dB. A 25 Gbps data transmission has been performed on its whole 12 optical links, and 8-channel wavelength division multiplexing data transmission has been implemented to expand its communication capacity. The energy efficiency of the device is 23 fJ/bit, and the response time of the device is about 25 μs.

  13. An interleaver with tunable bandwidth ratio based on microring resonator coupled Mach-Zehnder interferometer

    NASA Astrophysics Data System (ADS)

    Xu, Chi; Zhang, Yundong; Zhang, Xuenan; Wang, Kaiyang; Wu, Yongfeng; Zhai, Xianxin; Yuan, Ping

    2015-03-01

    A fundamental structure of a passive interleaver based on microring resonator coupled Mach-Zehnder interferometer is proposed in this paper. The most conspicuous advantage is the simplicity, compactness of the structure and the flatness of the passband top. Then we propose two methods of realizing a bandwidth tunability in this structure. A further analysis shows that both methods have their own strengths. We expect the compact and flexible interleaver can provide some potential and important implications for upgrading a hybrid Dense Wavelength Division Multiplexing (DWDM) system.

  14. High-order all-optical differential equation solver based on microring resonators.

    PubMed

    Tan, Sisi; Xiang, Lei; Zou, Jinghui; Zhang, Qiang; Wu, Zhao; Yu, Yu; Dong, Jianji; Zhang, Xinliang

    2013-10-01

    We propose and experimentally demonstrate a feasible integrated scheme to solve all-optical differential equations using microring resonators (MRRs) that is capable of solving first- and second-order linear ordinary differential equations with different constant coefficients. Employing two cascaded MRRs with different radii, an excellent agreement between the numerical simulation and the experimental results is obtained. Due to the inherent merits of silicon-based devices for all-optical computing, such as low power consumption, small size, and high speed, this finding may motivate the development of integrated optical signal processors and further extend optical computing technologies.

  15. Mid-infrared ultra-high-Q resonators based on fluoride crystalline materials

    PubMed Central

    Lecaplain, C.; Javerzac-Galy, C.; Gorodetsky, M. L.; Kippenberg, T. J.

    2016-01-01

    The unavailability of highly transparent materials in the mid-infrared has been the main limitation in the development of ultra-sensitive molecular sensors or cavity-based spectroscopy applications. Whispering gallery mode microresonators have attained ultra-high-quality (Q) factor resonances in the near-infrared and visible. Here we report ultra-high Q factors in the mid-infrared using polished alkaline earth metal fluoride crystals. Using an uncoated chalcogenide tapered fibre as a high-ideality coupler in the mid-infrared, we study via cavity ringdown technique the losses of BaF2, CaF2, MgF2 and SrF2 microresonators. We show that MgF2 is limited by multiphonon absorption by studying the temperature dependence of the Q factor. In contrast, in SrF2 and BaF2 the lower multiphonon absorption leads to ultra-high Q factors at 4.5 μm. These values correspond to an optical finesse of , the highest value achieved for any type of mid-infrared resonator to date. PMID:27869119

  16. Mid-infrared ultra-high-Q resonators based on fluoride crystalline materials

    NASA Astrophysics Data System (ADS)

    Lecaplain, C.; Javerzac-Galy, C.; Gorodetsky, M. L.; Kippenberg, T. J.

    2016-11-01

    The unavailability of highly transparent materials in the mid-infrared has been the main limitation in the development of ultra-sensitive molecular sensors or cavity-based spectroscopy applications. Whispering gallery mode microresonators have attained ultra-high-quality (Q) factor resonances in the near-infrared and visible. Here we report ultra-high Q factors in the mid-infrared using polished alkaline earth metal fluoride crystals. Using an uncoated chalcogenide tapered fibre as a high-ideality coupler in the mid-infrared, we study via cavity ringdown technique the losses of BaF2, CaF2, MgF2 and SrF2 microresonators. We show that MgF2 is limited by multiphonon absorption by studying the temperature dependence of the Q factor. In contrast, in SrF2 and BaF2 the lower multiphonon absorption leads to ultra-high Q factors at 4.5 μm. These values correspond to an optical finesse of , the highest value achieved for any type of mid-infrared resonator to date.

  17. Mid-infrared ultra-high-Q resonators based on fluoride crystalline materials.

    PubMed

    Lecaplain, C; Javerzac-Galy, C; Gorodetsky, M L; Kippenberg, T J

    2016-11-21

    The unavailability of highly transparent materials in the mid-infrared has been the main limitation in the development of ultra-sensitive molecular sensors or cavity-based spectroscopy applications. Whispering gallery mode microresonators have attained ultra-high-quality (Q) factor resonances in the near-infrared and visible. Here we report ultra-high Q factors in the mid-infrared using polished alkaline earth metal fluoride crystals. Using an uncoated chalcogenide tapered fibre as a high-ideality coupler in the mid-infrared, we study via cavity ringdown technique the losses of BaF2, CaF2, MgF2 and SrF2 microresonators. We show that MgF2 is limited by multiphonon absorption by studying the temperature dependence of the Q factor. In contrast, in SrF2 and BaF2 the lower multiphonon absorption leads to ultra-high Q factors at 4.5 μm. These values correspond to an optical finesse of , the highest value achieved for any type of mid-infrared resonator to date.

  18. Thermoelastic damping in microrings with circular cross-section

    NASA Astrophysics Data System (ADS)

    Li, Pu; Fang, Yuming; Zhang, Jianrun

    2016-01-01

    Predicting thermoelastic damping (TED) is crucial in the design of high Q micro-resonators. Microrings are often critical components in many micro-resonators. Some analytical models for TED in microrings have already been developed in the past. However, the previous works are limited to the microrings with rectangular cross-section. The temperature field in the rectangular cross-section is one-dimensional. This paper deals with TED in the microrings with circular cross-section. The temperature field in the circular cross-section is two-dimensional. This paper first presents a 2-D analytical model for TED in the microrings with circular cross-section. Only the two-dimensional heat conduction in the circular cross-section is considered. The heat conduction along the circumferential direction of the microring is neglected in the 2-D model. Then the 2-D model has been extended to cover the circumferential heat conduction, and a 3-D analytical model for TED has been developed. The analytical results from the present 2-D and 3-D models show good agreement with the numerical results of FEM model. The limitations of the present 2-D analytical model are assessed.

  19. Casimir probe based upon metallized high Q SiN nanomembrane resonator.

    PubMed

    Garcia-Sanchez, Daniel; Fong, King Yan; Bhaskaran, Harish; Lamoreaux, Steve; Tang, Hong X

    2013-01-01

    We present the instrumentation and measurement scheme of a new Casimir force probe that bridges Casimir force measurements at microscale and macroscale. A metallized high Q silicon nitride nanomembrane resonator is employed as a sensitive force probe. The high tensile stress present in the nanomembrane not only enhances the quality factor but also maintains high flatness over large area serving as the bottom electrode in a sphere-plane configuration. A fiber interferometer is used to readout the oscillation of the nanomembrane and a phase-locked loop scheme is applied to track the change of the resonance frequency. Because of the high quality factor of the nanomembrane and the high stability of the setup, a frequency resolution down to 2 × 10(-9) and a corresponding force gradient resolution of 3 μN/m is achieved. Besides sensitive measurement of Casimir force, our measurement technique simultaneously offers Kelvin probe measurement capability that allows in situ imaging of the surface potentials.

  20. Time-domain measurement of optical transport in silicon micro-ring resonators.

    PubMed

    Pernice, Wolfram H P; Li, Mo; Tang, Hong X

    2010-08-16

    We perform time-domain measurements of optical transport dynamics in silicon nano-photonic devices. Using pulsed optical excitation the thermal and carrier induced optical nonlinearities of micro-ring resonators are investigated, allowing for identification of their individual contributions. Under pulsed excitation build-up of free carriers and heat in the waveguides leads to a beating oscillation of the cavity resonance frequency. When employing a burst of pulse trains shorter than the carrier life-time, the slower heating effect can be separated from the faster carrier effect. Our scheme provides a convenient way to thermally stabilize optical resonators for high-power time-domain applications and nonlinear optical conversion.

  1. Selective and reversible ammonia gas detection with nanoporous film functionalized silicon photonic micro-ring resonator.

    PubMed

    Yebo, Nebiyu A; Sree, Sreeprasanth Pulinthanathu; Levrau, Elisabeth; Detavernier, Christophe; Hens, Zeger; Martens, Johan A; Baets, Roel

    2012-05-21

    Portable, low cost and real-time gas sensors have a considerable potential in various biomedical and industrial applications. For such applications, nano-photonic gas sensors based on standard silicon fabrication technology offer attractive opportunities. Deposition of high surface area nano-porous coatings on silicon photonic sensors is a means to achieve selective, highly sensitive and multiplexed gas detection on an optical chip. Here we demonstrate selective and reversible ammonia gas detection with functionalized silicon-on-insulator optical micro-ring resonators. The micro-ring resonators are coated with acidic nano-porous aluminosilicate films for specific ammonia sensing, which results in a reversible response to NH(3)with selectivity relative to CO(2). The ammonia detection limit is estimated at about 5 ppm. The detectors reach a steady response to NH(3) within 30 and return to their base level within 60 to 90 seconds. The work opens perspectives on development of nano-photonic sensors for real-time, non-invasive, low cost and light weight biomedical and industrial sensing applications.

  2. Refractive Index-Based Detection of Gradient Elution Liquid Chromatography using Chip-Integrated Microring Resonator Arrays

    PubMed Central

    Wade, James H.; Bailey, Ryan C.

    2014-01-01

    Refractive index-based sensors offer attractive characteristics as non-destructive and universal detectors for liquid chromatographic separations, but a small dynamic range and sensitivity to minor thermal perturbations limit the utility of commercial RI detectors for many potential applications, especially those requiring the use of gradient elutions. As such, RI detectors find use almost exclusively in sample abundant, isocratic separations when interfaced with HPLC. Silicon photonic microring resonators are refractive index-sensitive optical devices that feature good sensitivity and tremendous dynamic range. The large dynamic range of microring resonators allows the sensors to function across a wide spectrum of refractive indices, such as that encountered when moving from an aqueous to organic mobile phase during a gradient elution – a key analytical advantage not supported in commercial RI detectors. Microrings are easily configured into sensor arrays, and chip-integrated control microrings enable real-time corrections of thermal drift. Thermal controls allow for analyses at any temperature and in the absence of rigorous temperature control, obviating extended detector equilibration wait times. Herein, proof of concept isocratic and gradient elution separations were performed using well characterized model analytes (e.g., caffeine, ibuprofen) in both neat buffer and more complex sample matrices. These experiments demonstrate the ability of microring arrays to perform isocratic and gradient elutions under ambient conditions, avoiding two major limitations of commercial RI-based detectors and maintaining comparable bulk RI sensitivity. Further benefit may be realized in the future through selective surface functionalization to impart degrees of post-column (bio)molecular specificity at the detection phase of a separation. The chip-based and microscale nature of microring resonators also makes it an attractive potential detection technology that could be

  3. Development of high-Q superconducting resonators for use as Kinetic Inductance detectors

    NASA Astrophysics Data System (ADS)

    Baselmans, J.; Barends, R.; Hovenier, N.; Gao, J.; Hoevers, H.; de Korte, P.; Klapwijk, T.

    One of the largest challenges in the development of future radiation detectors for space applications is the fabrication of large detector arrays This because future missions require camera s with many pixels in combination with background limited sensitivity Within this context we have started the development of Microwave Kinetic Inductance Detectors MKID s The MKID is a relatively new detector concept pioneered by J Zmuidzinas and P Day et al 1 which belongs to the class of pair breaking detectors where radiation is absorbed in a superconducting film by breaking Cooper pairs into quasiparticles The operating temperature of the device is 1 10 of the transition temperature of the superconducting film Hence an Aluminum KID should be operated at 100 mK The MKID measures the change in quasiparticle and Cooper pair density by probing the complex surface impedance of the superconductor This is done by making use of an extremely high Q superconducting quarter wavelength microwave thin film resonator Every resonator each with slightly different resonance frequency can be observed simultaneously With only one wideband cryogenic amplifier 2 coaxial cables from room temperature to the cold stage and commercially available readout electronics a camera with in excess of 100 000 pixels could become a reality KIDs can address the spectrum from far infrared to X-ray depending on the antenna or absorber coupled to the microwave resonator 1 P K Day H G LeDuc B A Mazin A Vayonakis and J Zmuidzinas Nature 425 p 817-821 2003

  4. High performance SOI microring resonator for biochemical sensing

    NASA Astrophysics Data System (ADS)

    Ciminelli, C.; Dell'Olio, F.; Conteduca, D.; Campanella, C. M.; Armenise, M. N.

    2014-07-01

    In this work we have investigated different silicon-on-insulator (SOI) microcavities based on a planar geometry having a footprint on chip as small as 100 μm2 with a ring, disk and hybrid configurations with the aim of being poorly intrusive for both in-body and out-of-body biosensing purposes. Accurate numerical results have been achieved by using the 3D finite element method and compared to 3D finite discrete time domain ones with a good agreement for both methods. The most promising resonator among the devices we have analyzed shows a Q-factor of the order of 105, that allows a limit of detection for the sensor equal to 10-6 RIU and a sensor sensitivity of 120 nm/RIU. The resonator has been designed for glucose biosensing, considering both the homogeneous sensing and the surface one, that enhances the sensor selectivity by the device functionalization with a glucose-oxidase (GOD) layer. The glucose concentration has been evaluated both with the microcavity surrounded by a water solution and with water only in the inner part of the cavity.

  5. Fano resonances in a multimode waveguide coupled to a high-Q silicon nitride ring resonator.

    PubMed

    Ding, Dapeng; de Dood, Michiel J A; Bauters, Jared F; Heck, Martijn J R; Bowers, John E; Bouwmeester, Dirk

    2014-03-24

    Silicon nitride (Si3N4) optical ring resonators provide exceptional opportunities for low-loss integrated optics. Here we study the transmission through a multimode waveguide coupled to a Si3N4 ring resonator. By coupling single-mode fibers to both input and output ports of the waveguide we selectively excite and probe combinations of modes in the waveguide. Strong asymmetric Fano resonances are observed and the degree of asymmetry can be tuned through the positions of the input and output fibers. The Fano resonance results from the interference between modes of the waveguide and light that couples resonantly to the ring resonator. We develop a theoretical model based on the coupled mode theory to describe the experimental results. The large extension of the optical modes out of the Si3N4 core makes this system promising for sensing applications.

  6. Photoconductive effect on p-i-p micro-heaters integrated in silicon microring resonators.

    PubMed

    Zhou, Linjie; Zhu, Haike; Zhang, Heng; Chen, Jianping

    2014-01-27

    We study the photoconductive effect of a p-i-p micro-heater integrated in a microring resonator. Due to the surface state absorption (SSA) and two photon absorption (TPA) of optical wave around 1550 nm, free carriers are generated in the silicon waveguide, leading to the modulation of silicon conductivity and thus the current flowing through it. The current-voltage (I-V) response of the p-i-p diode is dependent on the bias voltage and can be divided into ohmic-law regime and space-charge-limited regime. The resonance peak current is more sensitive to optical power in the ohmic-law regime. Such a phenomenon can also be utilized to monitor the optical power in the waveguide.

  7. Theoretical analysis of microring resonator-based biosensor with high resolution and free of temperature influence

    NASA Astrophysics Data System (ADS)

    Jian, Aoqun; Zou, Lu; Tang, Haiquan; Duan, Qianqian; Ji, Jianlong; Zhang, Qianwu; Zhang, Xuming; Sang, Shengbo

    2017-06-01

    The issue of thermal effects is inevitable for the ultrahigh refractive index (RI) measurement. A biosensor with parallel-coupled dual-microring resonator configuration is proposed to achieve high resolution and free thermal effects measurement. Based on the coupled-resonator-induced transparency effect, the design and principle of the biosensor are introduced in detail, and the performance of the sensor is deduced by simulations. Compared to the biosensor based on a single-ring configuration, the designed biosensor has a 10-fold increased Q value according to the simulation results, thus the sensor is expected to achieve a particularly high resolution. In addition, the output signal of the mathematical model of the proposed sensor can eliminate the thermal influence by adopting an algorithm. This work is expected to have great application potentials in the areas of high-resolution RI measurement, such as biomedical discoveries, virus screening, and drinking water safety.

  8. Ultrasensitive Detection of Testosterone Using Microring Resonator with Molecularly Imprinted Polymers

    PubMed Central

    Chen, Yangqing; Liu, Yong; Shen, Xiaodan; Chang, Zhimin; Tang, Longhua; Dong, Wen-Fei; Li, Mingyu; He, Jian-Jun

    2015-01-01

    We report ultrasensitive and highly selective detection of testosterone based on microring resonance sensor using molecularly imprinted polymers (MIP). A silicon-on-insulator (SOI) micoring resonator was modified by MIP films (MIPs) on a surface. The MIPs was synthesized by thermopolymerization using methacrylic acid as functional monomer and ethylene glycol dimethacrylate as crosslinking agent. The concentration of detected testosterone varies from 0.05 ng/mL to 10 ng/mL. The detection limit reaches 48.7 pg/mL. Ultrahigh sensitivity, good specificity and reproducibility have been demonstrated, indicating the great potential of making a cost effective and easy to operate lab-on-Chip and down scaling micro-fluidics devices in biosensing. PMID:26694390

  9. Reconfigurable electro-optical directed-logic circuit using carrier-depletion micro-ring resonators.

    PubMed

    Qiu, Ciyuan; Gao, Weilu; Soref, Richard; Robinson, Jacob T; Xu, Qianfan

    2014-12-15

    Here we demonstrate a reconfigurable electro-optical directed-logic circuit based on a regular array of integrated optical switches. Each 1×1 optical switch consists of a micro-ring resonator with an embedded lateral p-n junction and a micro-heater. We achieve high-speed on-off switching by applying electrical logic signals to the p-n junction. We can configure the operation mode of each switch by thermal tuning the resonance wavelength. The result is an integrated optical circuit that can be reconfigured to perform any combinational logic operation. As a proof-of-principle, we fabricated a multi-spectral directed-logic circuit based on a fourfold array of switches and showed that this circuit can be reconfigured to perform arbitrary two-input logic functions with speeds up to 3  GB/s.

  10. Requirements for gain/oscillation in Yb3+/Er3+-codoped microring resonators

    NASA Astrophysics Data System (ADS)

    Vallés, Juan A.; Gǎlǎtuş, R.

    2015-03-01

    A detailed model of the performance of a highly Yb3+/Er3+-codoped phosphate glass add-drop filter, which combines the propagation at resonance of both pump and signal powers inside the microring resonator with their interaction with the dopant ions, is used to analyze the requirements for gain/oscillation in these structures. Special attention is paid to the influence of additional coupling losses and asymmetry between the input/output couplers. It is concluded that, due to small signal gain saturation and the limited range of pump amplitude coupling coefficients, asymmetry does not greatly influence gain/oscillation requirements through the pump intensity build-up inside the ring. Asymmetry effect on small signal intensity transfer rate and threshold gain instead allows a significant lightening of the demanding doping ions concentrations requirements to achieve oscillation.

  11. Ultrasensitive Detection of Testosterone Using Microring Resonator with Molecularly Imprinted Polymers.

    PubMed

    Chen, Yangqing; Liu, Yong; Shen, Xiaodan; Chang, Zhimin; Tang, Longhua; Dong, Wen-Fei; Li, Mingyu; He, Jian-Jun

    2015-12-15

    We report ultrasensitive and highly selective detection of testosterone based on microring resonance sensor using molecularly imprinted polymers (MIP). A silicon-on-insulator (SOI) micoring resonator was modified by MIP films (MIPs) on a surface. The MIPs was synthesized by thermopolymerization using methacrylic acid as functional monomer and ethylene glycol dimethacrylate as crosslinking agent. The concentration of detected testosterone varies from 0.05 ng/mL to 10 ng/mL. The detection limit reaches 48.7 pg/mL. Ultrahigh sensitivity, good specificity and reproducibility have been demonstrated, indicating the great potential of making a cost effective and easy to operate lab-on-Chip and down scaling micro-fluidics devices in biosensing.

  12. Circular High-Q Resonating Isotropic Strain Sensors with Large Shift of Resonance Frequency under Stress

    PubMed Central

    Melik, Rohat; Unal, Emre; Perkgoz, Nihan Kosku; Puttlitz, Christian; Demir, Hilmi Volkan

    2009-01-01

    We present circular architecture bioimplant strain sensors that facilitate a strong resonance frequency shift with mechanical deformation. The clinical application area of these sensors is for in vivo assessment of bone fractures. Using a rectangular geometry, we obtain a resonance shift of 330 MHz for a single device and 170 MHz for its triplet configuration (with three side-by-side resonators on chip) under an applied load of 3,920 N. Using the same device parameters with a circular isotropic architecture, we achieve a resonance frequency shift of 500 MHz for the single device and 260 MHz for its triplet configuration, demonstrating substantially increased sensitivity. PMID:22303132

  13. Development of indium gallium arsenic phosphide/indium phosphide single-mode lasers using microring resonators for photonic integrated circuits

    NASA Astrophysics Data System (ADS)

    Park, Seoijin

    Microring resonators are a good candidate for high- density monolithically integrated photonic circuits due to their compact sizes. The microring resonators have a large resonant free spectral range because of their small cavity sizes. The free spectral range of 10 nm to 42 nm can be achieved with 20 μm to 5 μm diameter ring resonators. The wide free spectral ranges are very useful for developing single-mode lasers. The microring resonators can be realized with nanoscale strongly-confined waveguides. To characterize these waveguides, simulation tools involving finite difference method (FDM) tools have been developed. The simulation tools are verified for strongly confined straight and curved waveguides. Using the tools, the modification of spontaneous emission rates into guided modes from quantum wells in a strongly-confined waveguide is calculated. The calculation shows that by varying the aspect ratio of the waveguide, spontaneous emission into a desirable lasing mode is enhanced while emission into other modes is suppressed. To characterize beam propagation in the nanoscale strongly confined waveguides made of a semiconductor gain medium, finite difference time domain (FDTD) method as been developed and verified for one- dimensional case. The semiclassical density-matrix equations obtained with Markovian and non-Markovian approximations are combined with the Maxwell's equations and the combined equations are solved using FDTD approach. In our experimental study, we present InGaAsP/InP single- mode lasers using mircoring resonators for photonic integrated circuits. To fabricate the lasers composed of nanoscale strongly-lateral-confined waveguides, high density plasma etching methods such as inductively coupled plasma (ICP) etching and electron cyclotron resonance (ECR) etching using Cl2/N 2 based gas mixtures have been developed. The good etching results are demonstrated by using the etching method to realize room temperature operations of In

  14. Note: Vector network analyzer-ferromagnetic resonance spectrometer using high Q-factor cavity.

    PubMed

    Lo, C K; Lai, W C; Cheng, J C

    2011-08-01

    A ferromagnetic resonance (FMR) spectrometer whose main components consist of an X-band resonator and a vector network analyzer (VNA) was developed. This spectrometer takes advantage of a high Q-factor (9600) cavity and state-of-the-art VNA. Accordingly, field modulation lock-in technique for signal to noise ratio (SNR) enhancement is no longer necessary, and FMR absorption can therefore be extracted directly. Its derivative for the ascertainment of full width at half maximum height of FMR peak can be found by taking the differentiation of original data. This system was characterized with different thicknesses of permalloy (Py) films and its multilayer, and found that the SNR of 5 nm Py on glass was better than 50, and did not have significant reduction even at low microwave excitation power (-20 dBm), and at low Q-factor (3000). The FMR other than X-band can also be examined in the same manner by using a suitable band cavity within the frequency range of VNA.

  15. Note: Vector network analyzer-ferromagnetic resonance spectrometer using high Q-factor cavity

    NASA Astrophysics Data System (ADS)

    Lo, C. K.; Lai, W. C.; Cheng, J. C.

    2011-08-01

    A ferromagnetic resonance (FMR) spectrometer whose main components consist of an X-band resonator and a vector network analyzer (VNA) was developed. This spectrometer takes advantage of a high Q-factor (9600) cavity and state-of-the-art VNA. Accordingly, field modulation lock-in technique for signal to noise ratio (SNR) enhancement is no longer necessary, and FMR absorption can therefore be extracted directly. Its derivative for the ascertainment of full width at half maximum height of FMR peak can be found by taking the differentiation of original data. This system was characterized with different thicknesses of permalloy (Py) films and its multilayer, and found that the SNR of 5 nm Py on glass was better than 50, and did not have significant reduction even at low microwave excitation power (-20 dBm), and at low Q-factor (3000). The FMR other than X-band can also be examined in the same manner by using a suitable band cavity within the frequency range of VNA.

  16. Optimizing photon-pair generation electronically using a p-i-n diode incorporated in a silicon microring resonator

    NASA Astrophysics Data System (ADS)

    Savanier, Marc; Kumar, Ranjeet; Mookherjea, Shayan

    2015-09-01

    Silicon photonic microchips may be useful for compact, inexpensive, room-temperature optically pumped photon-pair sources, which unlike conventional photon-pair generators based on crystals or optical fibers, can be manufactured using CMOS-compatible processes on silicon wafers. It has been shown that photon pairs can be created in simple structures such as microring resonators at a rate of a few hundred kilohertz using less than a milliwatt of optical pump power, based on the process of spontaneous four-wave mixing. To create a practical photon-pair source, however, also requires some way of monitoring the device and aligning the pump wavelength when the temperature varies, since silicon resonators are highly sensitive to temperature. In fact, monitoring photodiodes are standard components in classical laser diodes, but the incorporation of germanium or InGaAs photodiodes would raise the cost and fabrication complexity. Here, we present a simple and effective all-electronic technique for finding the optimum operating point for the microring used to generate photon pairs, based on measuring the reverse-biased current in a silicon p-i-n junction diode fabricated across the waveguide that constitutes the silicon microring. We show that by monitoring the current, and using it to tune the pump laser wavelength, the photon-pair generation properties of the microring can be preserved over a temperature range of more than 30 °C.

  17. Optimizing photon-pair generation electronically using a p-i-n diode incorporated in a silicon microring resonator

    SciTech Connect

    Savanier, Marc Kumar, Ranjeet; Mookherjea, Shayan

    2015-09-28

    Silicon photonic microchips may be useful for compact, inexpensive, room-temperature optically pumped photon-pair sources, which unlike conventional photon-pair generators based on crystals or optical fibers, can be manufactured using CMOS-compatible processes on silicon wafers. It has been shown that photon pairs can be created in simple structures such as microring resonators at a rate of a few hundred kilohertz using less than a milliwatt of optical pump power, based on the process of spontaneous four-wave mixing. To create a practical photon-pair source, however, also requires some way of monitoring the device and aligning the pump wavelength when the temperature varies, since silicon resonators are highly sensitive to temperature. In fact, monitoring photodiodes are standard components in classical laser diodes, but the incorporation of germanium or InGaAs photodiodes would raise the cost and fabrication complexity. Here, we present a simple and effective all-electronic technique for finding the optimum operating point for the microring used to generate photon pairs, based on measuring the reverse-biased current in a silicon p-i-n junction diode fabricated across the waveguide that constitutes the silicon microring. We show that by monitoring the current, and using it to tune the pump laser wavelength, the photon-pair generation properties of the microring can be preserved over a temperature range of more than 30 °C.

  18. Solitons and frequency combs in silica microring resonators: Interplay of the Raman and higher-order dispersion effects

    NASA Astrophysics Data System (ADS)

    Milián, C.; Gorbach, A. V.; Taki, M.; Yulin, A. V.; Skryabin, D. V.

    2015-09-01

    The influence of Raman scattering and higher order dispersions on solitons and frequency comb generation in silica microring resonators is investigated. The Raman effect introduces a threshold value in the resonator quality factor above which the frequency-locked solitons cannot exist, and instead, a rich dynamics characterized by generation of self-frequency-shifting solitons and dispersive waves is observed. A mechanism for broadening the Cherenkov radiation through Hopf instability of the frequency-locked solitons is also reported.

  19. Modelling and simulation of a thermally induced optical transparency in a dual micro-ring resonator

    NASA Astrophysics Data System (ADS)

    Lydiate, Joseph

    2017-07-01

    This paper introduces the simulation and modelling of a novel dual micro-ring resonator. The geometric configuration of the resonators, and the implementation of a simulated broadband excitation source, results in the realization of optical transparencies in the combined through port output spectrum. The 130 nm silicon on insulator rib fabrication process is adopted for the simulation of the dual-ring configuration. Two titanium nitride heaters are positioned over the coupling regions of the resonators, which can be operated independently, to control the spectral position of the optical transparency. A third heater, centrally located above the dual resonator rings, can be used to red shift the entire spectrum to a required reference resonant wavelength. The free spectral range with no heater currents applied is 4.29 nm. For a simulated heater current of 7 mA (55.7 mW heater power) applied to one of the through coupling heaters, the optical transparency exhibits a red shift of 1.79 nm from the reference resonant wavelength. The ring-to-ring separation of approximately 900 nm means that it can be assumed that there is a zero ring-to-ring coupling field in this model. This novel arrangement has potential applications as a gas mass airflow sensor or a gas species identification sensor.

  20. Modelling and simulation of a thermally induced optical transparency in a dual micro-ring resonator.

    PubMed

    Lydiate, Joseph

    2017-07-01

    This paper introduces the simulation and modelling of a novel dual micro-ring resonator. The geometric configuration of the resonators, and the implementation of a simulated broadband excitation source, results in the realization of optical transparencies in the combined through port output spectrum. The 130 nm silicon on insulator rib fabrication process is adopted for the simulation of the dual-ring configuration. Two titanium nitride heaters are positioned over the coupling regions of the resonators, which can be operated independently, to control the spectral position of the optical transparency. A third heater, centrally located above the dual resonator rings, can be used to red shift the entire spectrum to a required reference resonant wavelength. The free spectral range with no heater currents applied is 4.29 nm. For a simulated heater current of 7 mA (55.7 mW heater power) applied to one of the through coupling heaters, the optical transparency exhibits a red shift of 1.79 nm from the reference resonant wavelength. The ring-to-ring separation of approximately 900 nm means that it can be assumed that there is a zero ring-to-ring coupling field in this model. This novel arrangement has potential applications as a gas mass airflow sensor or a gas species identification sensor.

  1. Modelling and simulation of a thermally induced optical transparency in a dual micro-ring resonator

    PubMed Central

    2017-01-01

    This paper introduces the simulation and modelling of a novel dual micro-ring resonator. The geometric configuration of the resonators, and the implementation of a simulated broadband excitation source, results in the realization of optical transparencies in the combined through port output spectrum. The 130 nm silicon on insulator rib fabrication process is adopted for the simulation of the dual-ring configuration. Two titanium nitride heaters are positioned over the coupling regions of the resonators, which can be operated independently, to control the spectral position of the optical transparency. A third heater, centrally located above the dual resonator rings, can be used to red shift the entire spectrum to a required reference resonant wavelength. The free spectral range with no heater currents applied is 4.29 nm. For a simulated heater current of 7 mA (55.7 mW heater power) applied to one of the through coupling heaters, the optical transparency exhibits a red shift of 1.79 nm from the reference resonant wavelength. The ring-to-ring separation of approximately 900 nm means that it can be assumed that there is a zero ring-to-ring coupling field in this model. This novel arrangement has potential applications as a gas mass airflow sensor or a gas species identification sensor. PMID:28791167

  2. Frequency-Temperature Compensation Techniques for High-Q Microwave Resonators

    NASA Astrophysics Data System (ADS)

    Hartnett, John G.; Tobar, Michael E.

    Low-noise high-stability resonator oscillators based on high-Q monolithic sapphire ``Whispering Gallery'' (WG)-mode resonators have become important devices for telecommunication, radar and metrological applications. The extremely high quality factor of sapphire, of 2 x10^5 at room temperature, 5 x10^7 at liquid nitrogen temperature and 5 x10^9 at liquid helium temperature has enabled the lowest phase noise and highly frequency-stable oscillators in the microwave regime to be constructed. To create an oscillator with exceptional frequency stability, the resonator must have its frequency-temperature dependence annulled at some temperature, as well as a high quality factor. The Temperature Coefficient of Permittivity (TCP) for sapphire is quite large, at 10-100parts per million/K above 77K. This mechanism allows temperature fluctuations to transform to resonator frequency fluctuations.A number of research groups worldwide have investigated various methods of compensating the TCP of a sapphire dielectric resonator at different temperatures. The usual electromagnetic technique of annulment involves the use of paramagnetic impurities contributing an opposite temperature coefficient of the magnetic susceptibility to the TCP. This technique has only been realized successfully in liquid helium environments. Near 4K the thermal expansion and permittivity effects are small and only small quantities of the paramagnetic ions are necessary to compensate the mode frequency. Compensation is due to impurity ions that were incidentally left over from the manufacturing process.Recently, there has been an effort to dispense with the need for liquid helium and make a compact flywheel oscillator for the new generation of primary frequency standards such as the cesium fountain at the Laboratoire Primaire du Temps et des Fréquences (LPTF), France. To achieve the stability limit imposed

  3. Four-channel optical add-drop multiplexer based on dual racetrack micro-ring resonators

    NASA Astrophysics Data System (ADS)

    Wu, Danning; Wu, Yuanda; Wang, Yue; An, Junming; Hu, Xiongwei

    2015-11-01

    In this paper we report on a four-channel optical add-drop multiplexer based on dual racetrack micro-ring resonators in submicron SOI rib waveguides. The free spectral range (FSR) is about 18.6 nm. The device can add/drop four optical channels in half C-band. When the device acts as an optical drop multiplexer, the channel spacing is about 1.5 nm, maximum extinction ratio is 23.75 dB, the minimum insertion loss 9.94 dB and the maximum adjacent channels crosstalk is -12.12 dB. When the device acts as an optical add multiplexer, the maximum extinction ratio is 28.72 dB and the minimum insertion loss 7.35 dB. The fabricated device has effectively and perfectly realized the signals upload and download.

  4. Microring-resonator-based four-port optical router for photonic networks-on-chip.

    PubMed

    Ji, Ruiqiang; Yang, Lin; Zhang, Lei; Tian, Yonghui; Ding, Jianfeng; Chen, Hongtao; Lu, Yangyang; Zhou, Ping; Zhu, Weiwei

    2011-09-26

    We design and fabricate a four-port optical router, which is composed of eight microring-resonator-based switching elements, four optical waveguides and six waveguide crossings. The extinction ratio is about 13 dB for the through port and larger than 30 dB for the drop port. The crosstalk of the measured optical links is less than -13 dB. The average tuning power consumption is about 10.37 mW and the tuning efficiency is 5.398 mW/nm. The routing functionality and optical signal integrity are verified by transmitting a 12.5 Gb/s PRBS optical signal. © 2011 Optical Society of America

  5. Deterministic single soliton generation and compression in microring resonators avoiding the chaotic region.

    PubMed

    Jaramillo-Villegas, Jose A; Xue, Xiaoxiao; Wang, Pei-Hsun; Leaird, Daniel E; Weiner, Andrew M

    2015-04-20

    A path within the parameter space of detuning and pump power is demonstrated in order to obtain a single cavity soliton (CS) with certainty in SiN microring resonators in the anomalous dispersion regime. Once the single CS state is reached, it is possible to continue a path to compress it, broadening the corresponding single free spectral range (FSR) Kerr frequency comb. The first step to achieve this goal is to identify the stable regions in the parameter space via numerical simulations of the Lugiato-Lefever equation (LLE). Later, using this identification, we define a path from the stable modulation instability (SMI) region to the stable cavity solitons (SCS) region avoiding the chaotic and unstable regions.

  6. Electro-optic directed XOR logic circuits based on parallel-cascaded micro-ring resonators.

    PubMed

    Tian, Yonghui; Zhao, Yongpeng; Chen, Wenjie; Guo, Anqi; Li, Dezhao; Zhao, Guolin; Liu, Zilong; Xiao, Huifu; Liu, Guipeng; Yang, Jianhong

    2015-10-05

    We report an electro-optic photonic integrated circuit which can perform the exclusive (XOR) logic operation based on two silicon parallel-cascaded microring resonators (MRRs) fabricated on the silicon-on-insulator (SOI) platform. PIN diodes embedded around MRRs are employed to achieve the carrier injection modulation. Two electrical pulse sequences regarded as two operands of operations are applied to PIN diodes to modulate two MRRs through the free carrier dispersion effect. The final operation result of two operands is output at the Output port in the form of light. The scattering matrix method is employed to establish numerical model of the device, and numerical simulator SG-framework is used to simulate the electrical characteristics of the PIN diodes. XOR operation with the speed of 100Mbps is demonstrated successfully.

  7. Demonstration of a 3-bit optical digital-to-analog converter based on silicon microring resonators.

    PubMed

    Yang, Lin; Ding, Jianfeng; Chen, Qiaoshan; Zhou, Ping; Zhang, Fanfan; Zhang, Lei

    2014-10-01

    We propose an N-bit optical digital-to-analog converter based on silicon microring resonators (MRRs), which can transform an N-bit electrical digital signal to an optical analog signal. A 3-bit optical digital-to-analog convertor is fabricated as proof of concept through a CMOS-compatible process on a silicon-on-insulator platform. The silicon MRRs are modulated through the electric-field-induced carrier injection in forward biased PN junctions embedded in the ring waveguides. The electro-optical 3-dB bandwidths of the silicon MRRs are approximately 800 MHz. The device works well at a speed of 500  MSample/s under driving voltage swings of 0.75 V.

  8. Optical bistability in a silicon nitride microring resonator with azo dye-doped liquid crystal as cladding material.

    PubMed

    Wang, Chun-Ta; Tseng, Chih-Wei; Yu, Jui-Hao; Li, Yuan-Cheng; Lee, Chun-Hong; Jau, Hung-Chang; Lee, Ming-Chang; Chen, Yung-Jui; Lin, Tsung-Hsien

    2013-05-06

    This investigation reports observations of optical bistability in a silicon nitride (SiN) micro-ring resonator with azo dye-doped liquid crystal cladding. The refractive index of the cladding can be changed by switching the liquid crystal between nematic (NLC) and photo-induced isotropic (PHI) states by. Both the NLC and the PHI states can be maintained for many hours, and can be rapidly switched from one state to the other by photo-induced isomerization using 532 nm and 408 nm addressing light, respectively. The proposed device exhibits optical bistable switching of the resonance wavelength without sustained use of a power source. It has a 1.9 nm maximum spectral shift with a Q-factor of over 10000. The hybrid SiN- LC micro-ring resonator possesses easy switching, long memory, and low power consumption. It therefore has the potential to be used in signal processing elements and switching elements in optically integrated circuits.

  9. Carbon Nanofiber-Based, High-Frequency, High-Q, Miniaturized Mechanical Resonators

    NASA Technical Reports Server (NTRS)

    Kaul, Anupama B.; Epp, Larry W.; Bagge, Leif

    2011-01-01

    High Q resonators are a critical component of stable, low-noise communication systems, radar, and precise timing applications such as atomic clocks. In electronic resonators based on Si integrated circuits, resistive losses increase as a result of the continued reduction in device dimensions, which decreases their Q values. On the other hand, due to the mechanical construct of bulk acoustic wave (BAW) and surface acoustic wave (SAW) resonators, such loss mechanisms are absent, enabling higher Q-values for both BAW and SAW resonators compared to their electronic counterparts. The other advantages of mechanical resonators are their inherently higher radiation tolerance, a factor that makes them attractive for NASA s extreme environment planetary missions, for example to the Jovian environments where the radiation doses are at hostile levels. Despite these advantages, both BAW and SAW resonators suffer from low resonant frequencies and they are also physically large, which precludes their integration into miniaturized electronic systems. Because there is a need to move the resonant frequency of oscillators to the order of gigahertz, new technologies and materials are being investigated that will make performance at those frequencies attainable. By moving to nanoscale structures, in this case vertically oriented, cantilevered carbon nanotubes (CNTs), that have larger aspect ratios (length/thickness) and extremely high elastic moduli, it is possible to overcome the two disadvantages of both bulk acoustic wave (BAW) and surface acoustic wave (SAW) resonators. Nano-electro-mechanical systems (NEMS) that utilize high aspect ratio nanomaterials exhibiting high elastic moduli (e.g., carbon-based nanomaterials) benefit from high Qs, operate at high frequency, and have small force constants that translate to high responsivity that results in improved sensitivity, lower power consumption, and im - proved tunablity. NEMS resonators have recently been demonstrated using topdown

  10. Meta-metallic coils and resonators: Methods for high Q-value resonant geometries

    SciTech Connect

    Mett, R. R.; Sidabras, J. W.; Hyde, J. S.

    2016-08-15

    A novel method of decreasing ohmic losses and increasing Q-value in metallic resonators at high frequencies is presented. The method overcomes the skin-depth limitation of rf current flow cross section. The method uses layers of conductive foil of thickness less than a skin depth and capacitive gaps between layers. The capacitive gaps can substantially equalize the rf current flowing in each layer, resulting in a total cross-sectional dimension for rf current flow many times larger than a skin depth. Analytic theory and finite-element simulations indicate that, for a variety of structures, the Q-value enhancement over a single thick conductor approaches the ratio of total conductor thickness to skin depth if the total number of layers is greater than one-third the square of the ratio of total conductor thickness to skin depth. The layer number requirement is due to counter-currents in each foil layer caused by the surrounding rf magnetic fields. We call structures that exhibit this type of Q-enhancement “meta-metallic.” In addition, end effects due to rf magnetic fields wrapping around the ends of the foils can substantially reduce the Q-value for some classes of structures. Foil structures with Q-values that are substantially influenced by such end effects are discussed as are five classes of structures that are not. We focus particularly on 400 MHz, which is the resonant frequency of protons at 9.4 T. Simulations at 400 MHz are shown with comparison to measurements on fabricated structures. The methods and geometries described here are general for magnetic resonance and can be used at frequencies much higher than 400 MHz.

  11. Meta-metallic coils and resonators: Methods for high Q-value resonant geometries.

    PubMed

    Mett, R R; Sidabras, J W; Hyde, J S

    2016-08-01

    A novel method of decreasing ohmic losses and increasing Q-value in metallic resonators at high frequencies is presented. The method overcomes the skin-depth limitation of rf current flow cross section. The method uses layers of conductive foil of thickness less than a skin depth and capacitive gaps between layers. The capacitive gaps can substantially equalize the rf current flowing in each layer, resulting in a total cross-sectional dimension for rf current flow many times larger than a skin depth. Analytic theory and finite-element simulations indicate that, for a variety of structures, the Q-value enhancement over a single thick conductor approaches the ratio of total conductor thickness to skin depth if the total number of layers is greater than one-third the square of the ratio of total conductor thickness to skin depth. The layer number requirement is due to counter-currents in each foil layer caused by the surrounding rf magnetic fields. We call structures that exhibit this type of Q-enhancement "meta-metallic." In addition, end effects due to rf magnetic fields wrapping around the ends of the foils can substantially reduce the Q-value for some classes of structures. Foil structures with Q-values that are substantially influenced by such end effects are discussed as are five classes of structures that are not. We focus particularly on 400 MHz, which is the resonant frequency of protons at 9.4 T. Simulations at 400 MHz are shown with comparison to measurements on fabricated structures. The methods and geometries described here are general for magnetic resonance and can be used at frequencies much higher than 400 MHz.

  12. Meta-metallic coils and resonators: Methods for high Q-value resonant geometries

    NASA Astrophysics Data System (ADS)

    Mett, R. R.; Sidabras, J. W.; Hyde, J. S.

    2016-08-01

    A novel method of decreasing ohmic losses and increasing Q-value in metallic resonators at high frequencies is presented. The method overcomes the skin-depth limitation of rf current flow cross section. The method uses layers of conductive foil of thickness less than a skin depth and capacitive gaps between layers. The capacitive gaps can substantially equalize the rf current flowing in each layer, resulting in a total cross-sectional dimension for rf current flow many times larger than a skin depth. Analytic theory and finite-element simulations indicate that, for a variety of structures, the Q-value enhancement over a single thick conductor approaches the ratio of total conductor thickness to skin depth if the total number of layers is greater than one-third the square of the ratio of total conductor thickness to skin depth. The layer number requirement is due to counter-currents in each foil layer caused by the surrounding rf magnetic fields. We call structures that exhibit this type of Q-enhancement "meta-metallic." In addition, end effects due to rf magnetic fields wrapping around the ends of the foils can substantially reduce the Q-value for some classes of structures. Foil structures with Q-values that are substantially influenced by such end effects are discussed as are five classes of structures that are not. We focus particularly on 400 MHz, which is the resonant frequency of protons at 9.4 T. Simulations at 400 MHz are shown with comparison to measurements on fabricated structures. The methods and geometries described here are general for magnetic resonance and can be used at frequencies much higher than 400 MHz.

  13. Meta-metallic coils and resonators: Methods for high Q-value resonant geometries

    PubMed Central

    Mett, R. R.; Hyde, J. S.

    2016-01-01

    A novel method of decreasing ohmic losses and increasing Q-value in metallic resonators at high frequencies is presented. The method overcomes the skin-depth limitation of rf current flow cross section. The method uses layers of conductive foil of thickness less than a skin depth and capacitive gaps between layers. The capacitive gaps can substantially equalize the rf current flowing in each layer, resulting in a total cross-sectional dimension for rf current flow many times larger than a skin depth. Analytic theory and finite-element simulations indicate that, for a variety of structures, the Q-value enhancement over a single thick conductor approaches the ratio of total conductor thickness to skin depth if the total number of layers is greater than one-third the square of the ratio of total conductor thickness to skin depth. The layer number requirement is due to counter-currents in each foil layer caused by the surrounding rf magnetic fields. We call structures that exhibit this type of Q-enhancement “meta-metallic.” In addition, end effects due to rf magnetic fields wrapping around the ends of the foils can substantially reduce the Q-value for some classes of structures. Foil structures with Q-values that are substantially influenced by such end effects are discussed as are five classes of structures that are not. We focus particularly on 400 MHz, which is the resonant frequency of protons at 9.4 T. Simulations at 400 MHz are shown with comparison to measurements on fabricated structures. The methods and geometries described here are general for magnetic resonance and can be used at frequencies much higher than 400 MHz. PMID:27587143

  14. Multiplexed detection of lectins using integrated glycan-coated microring resonators.

    PubMed

    Ghasemi, Farshid; Hosseini, Ehsan Shah; Song, Xuezheng; Gottfried, David S; Chamanzar, Maysamreza; Raeiszadeh, Mehrsa; Cummings, Richard D; Eftekhar, Ali A; Adibi, Ali

    2016-06-15

    We present the systematic design, fabrication, and characterization of a multiplexed label-free lab-on-a-chip biosensor using silicon nitride (SiN) microring resonators. Sensor design is addressed through a systematic approach that enables optimizing the sensor according to the specific noise characteristics of the setup. We find that an optimal 6 dB undercoupled resonator consumes 40% less power in our platform to achieve the same limit-of-detection as the conventional designs using critically coupled resonators that have the maximum light-matter interaction. We lay out an optimization framework that enables the generalization of our method for any type of optical resonator and noise characteristics. The device is fabricated using a CMOS-compatible process, and an efficient swabbing lift-off technique is introduced for the deposition of the protective oxide layer. This technique increases the lift-off quality and yield compared to common lift-off methods based on agitation. The complete sensor system, including microfluidic flow cell and surface functionalization with glycan receptors, is tested for the multiplexed detection of Aleuria Aurantia Lectin (AAL) and Sambucus Nigra Lectin (SNA). Further analysis shows that the sensor limit of detection is 2 × 10(-6) RIU for bulk refractive index, 1 pg/mm(2) for surface-adsorbed mass, and ∼ 10 pM for the glycan/lectins studied here. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. An optic fiber sensor for multiple gases based on fiber loop ring-down spectroscopy and microring resonator arrays

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Jian, Jia-wen; Zheng, Yan-gong; Jin, Han; Zou, Jie

    2016-07-01

    A high-sensitivity sensor for multiple gases based on microring array filter and fiber loop ring-down spectroscopy system is proposed and demonstrated. The parameters of the resonators are designed so that the filtered signal from a broadband light source can be tuned with an absorption spectral line of gas. Therefore, through adding microring resonators horizontally and vertically, the number of target gases and filter range are increased. In this research, in the broad spectral range of about 0.9 μm, only the absorption spectral lines of target gases are filtered. The simulation results show that three target gases, CH4, CO2 and HF, can be simultaneously detected by the sensing system. Owing to the fiber loop ring-down spectroscopy, the whole system is optimized in mini-size and sensitivity, and we can choose different sensing methods to enhance the measurement accuracy for high and low concentration conditions.

  16. Proof of concept of directed OR/NOR and AND/NAND logic circuit consisting of two parallel microring resonators.

    PubMed

    Tian, Yonghui; Zhang, Lei; Ji, Ruiqiang; Yang, Lin; Zhou, Ping; Chen, Hongtao; Ding, Jianfeng; Zhu, Weiwei; Lu, Yangyang; Jia, Lianxi; Fang, Qing; Yu, Mingbin

    2011-05-01

    We propose and demonstrate a directed OR/NOR and AND/NAND logic circuit consisting of two parallel microring resonators (MRRs). We use two electrical signals representing the two operands of the logical operation to modulate the two MRRs through the thermo-optic effect, respectively. The final operation results are represented by the output optical signals. Both OR/NOR and AND/NAND operations at 10 kbps are demonstrated.

  17. Integrated label-free optical biochemical sensor with a large measurement range based on an angular grating-microring resonator.

    PubMed

    Ma, Tao; Sun, Lei; Yuan, Jinhui; Sang, Xinzhu; Yan, Binbin; Wang, Kuiru; Yu, Chongxiu

    2016-06-20

    We propose and design a photonic-integrated optical biochemical sensor, which comprises a microring resonator and angular gratings in a silicon-on-insulator waveguide. With the combination of the angular gratings, the measurement range of the angular grating-microring resonator-based sensor significantly increases without the restriction of a free spectral range. Optimization of the several key structural parameters is investigated to achieve favorable transmission properties. A high-quality factor of more than 1.03×105 can meet the requirements of high sensitivity and low detection limit. The simulation results on the biochemical bulk sensing show that a concentration sensitivity of more than 95.27 pm/% and detection limit of less than 0.329% can be obtained. A large measurement range of 50.2 nm is achieved by the combination of the angular gratings. The investigation on the combination of microring resonator and angular grating is a valuable exploration of the liquid and gas biomedical sensing for the ultra-large measurement range.

  18. Anti-DNA:RNA antibodies and silicon photonic microring resonators: increased sensitivity for multiplexed microRNA detection.

    PubMed

    Qavi, Abraham J; Kindt, Jared T; Gleeson, Martin A; Bailey, Ryan C

    2011-08-01

    In this paper, we present a method for the sensitive detection of microRNAs (miRNAs) utilizing an antibody that specifically recognizes DNA:RNA heteroduplexes and a silicon photonic microring resonator array transduction platform. Microring resonator arrays are covalently functionalized with DNA capture probes that are complementary to solution phase miRNA targets. Following hybridization on the sensor, the anti-DNA:RNA antibody is introduced and binds selectively to the heteroduplexes, giving a larger signal than the original miRNA hybridization due to the increased mass of the antibody, as compared to the 22-mer oligoribonucleotide. Furthermore, the secondary recognition step is performed in neat buffer solution and at relatively higher antibody concentrations, facilitating the detection of miRNAs of interest. The intrinsic sensitivity of the microring resonator platform coupled with the amplification provided by the anti-DNA:RNA antibodies allows for the detection of microRNAs at concentrations as low as 10 pM (350 amol). The simplicity and sequence generality of this amplification method position it as a promising tool for high-throughput, multiplexed miRNA analysis as well as a range of other RNA based detection applications.

  19. The effects of periodic and quasi-periodic orders on the photonic bandgap structures of microring coupled-resonator optical waveguides.

    PubMed

    Ang, Thomas Y L; Chin, Mee Koy

    2009-03-30

    We present a coupling matrix formalism to investigate the effects of periodic and quasi-periodic orders on the photonic bandgap (PBG) structures of coupled-resonator optical waveguides (CROWs) based on microring resonators. For the periodic order case, size-tuned defects are introduced at periodic locations among the regular rings, which are size-untuned, to form a periodic ordered CROW system. The periodic coupled defects result in multiple localization states that lead to the formation of mini-defect bands and mini-PBGs within the PBG of a defect-free CROW. The position and number of such mini-defect bands depend on the size tuning of the defects. For the quasi-periodic order case, the arrangement of the defects and the regular rings in the ring cascade is an intermediate between periodic order and randomness, thus forming a quasi-periodic ordered CROW system. The effects of quasi-periodicity on the PBG structures are illustrated using the Fibonacci sequences, which result in a single high-Q localized state to appear that gradually transits to a mini-band within a wide photonic stop band as the number of lattice cells increases.

  20. Numerical investigation into a surface plasmon resonance sensor based on optical fiber microring

    NASA Astrophysics Data System (ADS)

    Zhao, Chunliu; Wang, Yanru; Wang, Dongning; Ding, Zhewen

    2017-06-01

    A reflective surface plasmon resonance (SPR) sensor based on optical fiber microring is proposed. In such a sensor, plasmons on the outer surface of the metallized channels containing analyte can be excited by a fundamental mode of a thin-core fiber (TCF). The refractive index (RI) sensing can be achieved as the surface plasmons are sensitive to changes in the refrective index of the analyte. Numerical simulation results show that the resonance spectrum shifts toward the shorter wavelength gradually when the analyte refractive index increases from 1.0 to 1.33, whereas it shifts toward the longer wavelength gradually when the analyte refractive index increases from 1.33 to 1.43, and there is a turning point at the refractive index value of 1.33. The highest sensitivity achieved is up to 2.30×103 nm/RIU near the refractive index value of 1.0. Such a compact sensor has potential in gaseous substance monitoring.

  1. Numerical investigation into a surface plasmon resonance sensor based on optical fiber microring

    NASA Astrophysics Data System (ADS)

    Zhao, Chunliu; Wang, Yanru; Wang, Dongning; Ding, Zhewen

    2017-01-01

    A reflective surface plasmon resonance (SPR) sensor based on optical fiber microring is proposed. In such a sensor, plasmons on the outer surface of the metallized channels containing analyte can be excited by a fundamental mode of a thin-core fiber (TCF). The refractive index (RI) sensing can be achieved as the surface plasmons are sensitive to changes in the refrective index of the analyte. Numerical simulation results show that the resonance spectrum shifts toward the shorter wavelength gradually when the analyte refractive index increases from 1.0 to 1.33, whereas it shifts toward the longer wavelength gradually when the analyte refractive index increases from 1.33 to 1.43, and there is a turning point at the refractive index value of 1.33. The highest sensitivity achieved is up to 2.30×103 nm/RIU near the refractive index value of 1.0. Such a compact sensor has potential in gaseous substance monitoring.

  2. Wide-range and fast thermally-tunable silicon photonic microring resonators using the junction field effect.

    PubMed

    Wang, Xiaoxi; Lentine, Anthony; DeRose, Christopher; Starbuck, Andrew L; Trotter, Douglas; Pomerene, Andrew; Mookherjea, Shayan

    2016-10-03

    Tunable silicon microring resonators with small, integrated micro-heaters which exhibit a junction field effect were made using a conventional silicon-on-insulator (SOI) photonic foundry fabrication process. The design of the resistive tuning section in the microrings included a "pinched" p-n junction, which limited the current at higher voltages and inhibited damage even when driven by a pre-emphasized voltage waveform. Dual-ring filters were studied for both large (>4.9 THz) and small (850 GHz) free-spectral ranges. Thermal red-shifting was demonstrated with microsecond-scale time constants, e.g., a dual-ring filter was tuned over 25 nm in 0.6 μs 10%-90% transition time, and with efficiency of 3.2 μW/GHz.

  3. Wide-range and fast thermally-tunable silicon photonic microring resonators using the junction field effect

    DOE PAGES

    Wang, Xiaoxi; Lentine, Anthony; DeRose, Christopher; ...

    2016-09-26

    Tunable silicon microring resonators with small, integrated micro-heaters which exhibit a junction field effect were made using a conventional silicon-on-insulator (SOI) photonic foundry fabrication process. The design of the resistive tuning section in the microrings included a “pinched” p-n junction, which limited the current at higher voltages and inhibited damage even when driven by a pre-emphasized voltage waveform. Dual-ring filters were studied for both large (>4.9 THz) and small (850 GHz) free-spectral ranges. In conclusion, thermal red-shifting was demonstrated with microsecond-scale time constants, e.g., a dual-ring filter was tuned over 25 nm in 0.6 μs 10%–90% transition time, and withmore » efficiency of 3.2 μW/GHz.« less

  4. Wide-range and fast thermally-tunable silicon photonic microring resonators using the junction field effect

    DOE PAGES

    Wang, Xiaoxi; Lentine, Anthony; DeRose, Christopher; ...

    2016-09-26

    Tunable silicon microring resonators with small, integrated micro-heaters which exhibit a junction field effect were made using a conventional silicon-on-insulator (SOI) photonic foundry fabrication process. The design of the resistive tuning section in the microrings included a “pinched” p-n junction, which limited the current at higher voltages and inhibited damage even when driven by a pre-emphasized voltage waveform. Dual-ring filters were studied for both large (>4.9 THz) and small (850 GHz) free-spectral ranges. In conclusion, thermal red-shifting was demonstrated with microsecond-scale time constants, e.g., a dual-ring filter was tuned over 25 nm in 0.6 μs 10%–90% transition time, and withmore » efficiency of 3.2 μW/GHz.« less

  5. Wide-range and fast thermally-tunable silicon photonic microring resonators using the junction field effect

    SciTech Connect

    Wang, Xiaoxi; Lentine, Anthony; DeRose, Christopher; Starbuck, Andrew L.; Trotter, Douglas; Pomerene, Andrew; Mookherjea, Shayan

    2016-09-26

    Tunable silicon microring resonators with small, integrated micro-heaters which exhibit a junction field effect were made using a conventional silicon-on-insulator (SOI) photonic foundry fabrication process. The design of the resistive tuning section in the microrings included a “pinched” p-n junction, which limited the current at higher voltages and inhibited damage even when driven by a pre-emphasized voltage waveform. Dual-ring filters were studied for both large (>4.9 THz) and small (850 GHz) free-spectral ranges. In conclusion, thermal red-shifting was demonstrated with microsecond-scale time constants, e.g., a dual-ring filter was tuned over 25 nm in 0.6 μs 10%–90% transition time, and with efficiency of 3.2 μW/GHz.

  6. High quality factor subwavelength grating waveguide micro-ring resonator based on trapezoidal silicon pillars.

    PubMed

    Wang, Zheng; Xu, Xiaochuan; Fan, Donglei; Wang, Yaguo; Chen, Ray T

    2016-07-15

    Subwavelength grating waveguide-based micro-ring resonators (SWGMRs) are a promising platform for research in light-matter interaction. However, it is extremely difficult to achieve small radius SWGMR devices (e.g., 5 μm) with satisfying quality factors (e.g., ∼10,000). One major issue is the large bend loss of small radius SWGMRs. In this work, we report the use of trapezoidal silicon pillars instead of conventional rectangular silicon pillars as building blocks of SWGMRs. We found that an asymmetric effective refractive index profile created by trapezoidal silicon pillars can significantly reduce the bend loss and therefore increase the quality factors of SWGMRs. For the first time to the best of our knowledge, we have experimentally demonstrated a 5 μm radius SWGMR made of trapezoidal silicon pillars (T-SWGMR) with an applicable quality factor as high as 11,500, 4.6 times of that (∼2800) offered by a conventional SWGMR made of rectangular silicon pillars, which indicates an 81.4% reduction of the propagation loss. This approach can also be readily employed to enhance SWGMRs with larger radii. We have also experimentally demonstrated a 10 μm radius T-SWGMR with a quality factor as high as 45,000, which indicates a propagation loss as low as 6.07 dB/cm.

  7. A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy

    PubMed Central

    Li, Hao; Dong, Biqin; Zhang, Zhen; Zhang, Hao F.; Sun, Cheng

    2014-01-01

    Photoacoustic microscopy (PAM) does not rely on contrast agent to image the optical absorption contrast in biological tissue. It is uniquely suited for measuring several tissue physiological parameters, such as hemoglobin oxygen saturation, that would otherwise remain challenging. Researchers are designing new clinical diagnostic tools and multimodal microscopic systems around PAM to fully unleash its potential. However, the sizeable and opaque piezoelectric ultrasonic detectors commonly used in PAM impose a serious constraint. Our solution is a coverslip-style optically transparent ultrasound detector based on a polymeric optical micro-ring resonator (MRR) with a total thickness of 250 μm. It enables highly-sensitive ultrasound detection over a wide receiving angle with a bandwidth of 140 MHz, which corresponds to a photoacoustic saturation limit of 287 cm−1, at an estimated noise-equivalent pressure (NEP) of 6.8 Pa. We also established a theoretical framework for designing and optimizing the MRR for PAM. PMID:24675547

  8. Rectangular optical filter based on high-order silicon microring resonators

    NASA Astrophysics Data System (ADS)

    Bao, Jia-qi; Yu, Kan; Wang, Li-jun; Yin, Juan-juan

    2017-07-01

    The rectangular optical filter is one of the most important optical switching components in the dense wavelength division multiplexing (DWDM) fiber-optic communication system and the intelligent optical network. The integrated highorder silicon microring resonator (MRR) is one of the best candidates to achieve rectangular filtering spectrum response. In general, the spectrum response rectangular degree of the single MRR is very low, so it cannot be used in the DWDM system. Using the high-order MRRs, the bandwidth of flat-top pass band, the out-of-band rejection degree and the roll-off coefficient of the edge will be improved obviously. In this paper, a rectangular optical filter based on highorder MRRs with uniform couplers is presented and demonstrated. Using 15 coupled race-track MRRs with 10 μm in radius, the 3 dB flat-top pass band of 2 nm, the out-of-band rejection ratio of 30 dB and the rising and falling edges of 48 dB/nm can be realized successfully.

  9. Zwitterionic polymer-modified silicon microring resonators for label-free biosensing in undiluted human plasma.

    PubMed

    Kirk, James T; Brault, Norman D; Baehr-Jones, Tom; Hochberg, Michael; Jiang, Shaoyi; Ratner, Daniel M

    2013-04-15

    A widely acknowledged goal in personalized medicine is to radically reduce the costs of highly parallelized, small fluid volume, point-of-care and home-based diagnostics. Recently, there has been a surge of interest in using complementary metal-oxide-semiconductor (CMOS)-compatible silicon photonic circuits for biosensing, with the promise of producing chip-scale integrated devices containing thousands of orthogonal sensors, at minimal cost on a per-chip basis. A central challenge in biosensor translation is to engineer devices that are both sensitive and specific to a target analyte within unprocessed biological fluids. Despite advances in the sensitivity of silicon photonic biosensors, poor biological specificity at the sensor surface remains a significant factor limiting assay performance in complex media (i.e. whole blood, plasma, serum) due to the non-specific adsorption of proteins and other biomolecules. Here, we chemically modify the surface of silicon microring resonator biosensors for the label-free detection of an analyte in undiluted human plasma. This work highlights the first application of a non-fouling zwitterionic surface coating to enable silicon photonic-based label-free detection of a protein analyte at clinically relevant sensitivities in undiluted human plasma.

  10. Chip-integrated optical power limiter based on an all-passive micro-ring resonator.

    PubMed

    Yan, Siqi; Dong, Jianji; Zheng, Aoling; Zhang, Xinliang

    2014-10-20

    Recent progress in silicon nanophotonics has dramatically advanced the possible realization of large-scale on-chip optical interconnects integration. Adopting photons as information carriers can break the performance bottleneck of electronic integrated circuit such as serious thermal losses and poor process rates. However, in integrated photonics circuits, few reported work can impose an upper limit of optical power therefore prevent the optical device from harm caused by high power. In this study, we experimentally demonstrate a feasible integrated scheme based on a single all-passive micro-ring resonator to realize the optical power limitation which has a similar function of current limiting circuit in electronics. Besides, we analyze the performance of optical power limiter at various signal bit rates. The results show that the proposed device can limit the signal power effectively at a bit rate up to 20 Gbit/s without deteriorating the signal. Meanwhile, this ultra-compact silicon device can be completely compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may pave the way of very large scale integrated photonic circuits for all-optical information processors and artificial intelligence systems.

  11. Chip-integrated optical power limiter based on an all-passive micro-ring resonator

    PubMed Central

    Yan, Siqi; Dong, Jianji; Zheng, Aoling; Zhang, Xinliang

    2014-01-01

    Recent progress in silicon nanophotonics has dramatically advanced the possible realization of large-scale on-chip optical interconnects integration. Adopting photons as information carriers can break the performance bottleneck of electronic integrated circuit such as serious thermal losses and poor process rates. However, in integrated photonics circuits, few reported work can impose an upper limit of optical power therefore prevent the optical device from harm caused by high power. In this study, we experimentally demonstrate a feasible integrated scheme based on a single all-passive micro-ring resonator to realize the optical power limitation which has a similar function of current limiting circuit in electronics. Besides, we analyze the performance of optical power limiter at various signal bit rates. The results show that the proposed device can limit the signal power effectively at a bit rate up to 20 Gbit/s without deteriorating the signal. Meanwhile, this ultra-compact silicon device can be completely compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may pave the way of very large scale integrated photonic circuits for all-optical information processors and artificial intelligence systems. PMID:25327538

  12. Chip-integrated optical power limiter based on an all-passive micro-ring resonator

    NASA Astrophysics Data System (ADS)

    Yan, Siqi; Dong, Jianji; Zheng, Aoling; Zhang, Xinliang

    2014-10-01

    Recent progress in silicon nanophotonics has dramatically advanced the possible realization of large-scale on-chip optical interconnects integration. Adopting photons as information carriers can break the performance bottleneck of electronic integrated circuit such as serious thermal losses and poor process rates. However, in integrated photonics circuits, few reported work can impose an upper limit of optical power therefore prevent the optical device from harm caused by high power. In this study, we experimentally demonstrate a feasible integrated scheme based on a single all-passive micro-ring resonator to realize the optical power limitation which has a similar function of current limiting circuit in electronics. Besides, we analyze the performance of optical power limiter at various signal bit rates. The results show that the proposed device can limit the signal power effectively at a bit rate up to 20 Gbit/s without deteriorating the signal. Meanwhile, this ultra-compact silicon device can be completely compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may pave the way of very large scale integrated photonic circuits for all-optical information processors and artificial intelligence systems.

  13. A study on refractive index sensors based on optical micro-ring resonators

    NASA Astrophysics Data System (ADS)

    Tsigaridas, Georgios N.

    2017-09-01

    In this work, the behavior of refractive index sensors based on optical micro-ring resonators is studied in detail. Using a result of waveguide perturbation theory in combination with numerical simulations, the optimum design parameters of the system, maximizing the sensitivity of the sensor, are determined. It is found that, when optimally designed, the sensor can detect relative refractive index changes of the order of Δ n/ n≈3×10-4, assuming that the experimental setup can detect relative wavelength shifts of the order of Δ λ/λ≈3×10-5. The behavior of the system as bio-sensor has also been examined. It is found that, when optimally designed, the system can detect refractive index changes of the order of Δ n≈10-3 for a layer thickness of t=10 nm, and changes in the layer thickness of the order of λ t≈0.24 nm, for a refractive index change of Δ n=0.05.

  14. On-chip interrogation of a silicon-on-insulator microring resonator-based ethanol vapor sensor with an arrayed waveguide grating (AWG) spectrometer

    NASA Astrophysics Data System (ADS)

    Yebo, Nebiyu A.; Bogaerts, Wim; Hens, Zeger; Baets, Roel

    2012-01-01

    Silicon -on -insulator (SOI) optical microring resonators fabricated with the standard CMOS fabrication technology have recently gained considerable attention for energy efficient, compact and low cost biomedical and environmental sensing applications. High sensitivity to the surrounding refractive index variations, high compactness, direct wavelength multiplexing capabilities, simplicity, and the promise for mass fabrication are among the interesting features supported by SOI microring resonators. On the other hand, despite the strong case for microring resonators for sensing, there exist some issues which need to be addressed in order to ensure the feasibility of such sensors. One major limitation currently is the cost of optical sources and /or spectrum analyzers required to drive and interrogate these sensors. Either expensive light sources or spectrum analyzers are usually used with sensors built around microring resonators. An attractive approach to address this problem is the use of on-chip spectrometers along with cheap broadband light sources. We experimentally demonstrate on-chip interrogation of an SOI microring resonator based gas sensor with a compact Arrayed Waveguide Grating (AWG) spectrometer. We have designed and fabricated a 200GHz AWG with strongly overlapping output channels, and used it to interrogate the wavelength shift from a ring resonator based ethanol vapor sensor on the same chip. Ethanol vapor concentrations in 100-1000ppm range are readily detected by monitoring the intensity ratio between two adjacent AWG channels to which the microring resonance overlaps. Such an integrated sensor-interrogator approach is presented as an alternative to the current costly and off-chip read-out systems used for ring resonator based sensors.

  15. Differentially piezoresistive transduction of high-Q encapsulated SOI-MEMS resonators with sub-100 nm gaps.

    PubMed

    Li, Cheng-Syun; Li, Ming-Huang; Li, Sheng-Shian

    2015-01-01

    A differentially piezoresistive (piezo-R) readout proposed for single-crystal-silicon (SCS) microelectromechanical systems (MEMS) resonators is implemented in a foundrybased resonator platform, demonstrating effective feedthrough cancellation using just simple piezoresistors from the resonator supports while maximizing their capacitively transduced driving areas. The SCS resonators are fabricated by a CMOS foundry using an SOI-MEMS technology together with a polysilicon refill process. A high electromechanical coupling coefficient is attained by the use of 50-nm transducer gap spacing. Moreover, a vacuum package of the fabricated resonators is carried out through wafer-level bonding process. In this work, the corner supporting beams of the resonator serve not only mechanical supports but also piezoresistors for detecting the motional signal, hence substantially simplifying the overall resonator design to realize the piezo-R sensing. In addition, the fabricated resonators are capable of either capacitive sensing or piezo-R detection under the same capacitive drive. To mitigate feedthrough signals from parasitics, a differential measurement configuration of the piezo-R transduction is implemented in this work, featuring more than 30-dB improvement on the feedthrough level as compared with the single-ended piezo-R counterpart and purely capacitive sensing readout. Furthermore, the high-Q design of the mechanical supports is also investigated, offering Q more than 10 000 with efficient piezo-R transduction for MEMS resonators.

  16. Ultrafast all-optical arithmetic logic based on hydrogenated amorphous silicon microring resonators

    NASA Astrophysics Data System (ADS)

    Gostimirovic, Dusan; Ye, Winnie N.

    2016-03-01

    For decades, the semiconductor industry has been steadily shrinking transistor sizes to fit more performance into a single silicon-based integrated chip. This technology has become the driving force for advances in education, transportation, and health, among others. However, transistor sizes are quickly approaching their physical limits (channel lengths are now only a few silicon atoms in length), and Moore's law will likely soon be brought to a stand-still despite many unique attempts to keep it going (FinFETs, high-k dielectrics, etc.). This technology must then be pushed further by exploring (almost) entirely new methodologies. Given the explosive growth of optical-based long-haul telecommunications, we look to apply the use of high-speed optics as a substitute to the digital model; where slow, lossy, and noisy metal interconnections act as a major bottleneck to performance. We combine the (nonlinear) optical Kerr effect with a single add-drop microring resonator to perform the fundamental AND-XOR logical operations of a half adder, by all-optical means. This process is also applied to subtraction, higher-order addition, and the realization of an all-optical arithmetic logic unit (ALU). The rings use hydrogenated amorphous silicon as a material with superior nonlinear properties to crystalline silicon, while still maintaining CMOS-compatibility and the many benefits that come with it (low cost, ease of fabrication, etc.). Our method allows for multi-gigabit-per-second data rates while maintaining simplicity and spatial minimalism in design for high-capacity manufacturing potential.

  17. Microring resonator-based diamond optothermal switch: a building block for a quantum computing network

    NASA Astrophysics Data System (ADS)

    Huang, Zhihong; Faraon, Andrei; Santori, Charles; Acosta, Victor; Beausoleil, Raymond G.

    2013-03-01

    The negatively-charged nitrogen-vacancy centers in diamond has motivated many groups building scalable quantum information processors based on diamond photonics. This is owning to the long-lived electronic spin coherence and the capability for spin manipulation and readout of NV centers.1-4 The primitive operation is to create entanglement between two NV centers, based on schemes such as 'atom-photon entanglement' proposed by Cabrillo et al.5To scale this type of scheme beyond two qubits, one important component is an optical switch that allows light emitted from a particular device to be routed to multiple locations. With such a switch, one has choices of routing photons to specified paths and has the benefit of improving the entanglement speed by entangling multiple qubits at the same time. Yield of the existing diamond cavities coupled with NV centers are inevitably low, due to the nature of randomness for NV placement and orientation, variation of spectral stability, and variation of cavity resonance frequency and quality factor. An optical switch provides the capability to tolerate a large fraction of defective devices by routing only to the working devices. Many type of switching devices were built on conventional semiconductor materials with mechanisms from mechanical, thermal switching to carrier injection, photonics crystal, and polymer refractive index tuning .6-8 In this paper, we build an optical-thermal switch on diamond with micro-ring waveguides, mainly for the simplicity of the diamond fabrication. The the switching function was realized by locally tuning the temperature of the diamond waveguides. Switching efficiency of 31% at 'drop' port and 73% at 'through' port were obtained.

  18. High-Q cross-plate phononic crystal resonator for enhanced acoustic wave localization and energy harvesting

    NASA Astrophysics Data System (ADS)

    Yang, Aichao; Li, Ping; Wen, Yumei; Yang, Chao; Wang, Decai; Zhang, Feng; Zhang, Jiajia

    2015-05-01

    A high-Q cross-plate phononic crystal resonator (Cr-PCR) coupled with an electromechanical Helmholtz resonator (EMHR) is proposed to improve acoustic wave localization and energy harvesting. Owing to the strongly directional wave-scattering effect of the cross-plate corners, strong confinement of acoustic waves emerges. Consequently, the proposed Cr-PCR structure exhibits ∼353.5 times higher Q value and ∼6.1 times greater maximum pressure amplification than the phononic crystal resonator (Cy-PCR) (consisting of cylindrical scatterers) of the same size. Furthermore, the harvester using the proposed Cr-PCR and the EMHR has ∼22 times greater maximum output-power volume density than the previous harvester using Cy-PCR and EMHR structures.

  19. High-Q enhancement of attractive and repulsive optical forces between coupled whispering-gallery- mode resonators.

    PubMed

    Povinelli, Michelle; Johnson, Steven; Lonèar, Marko; Ibanescu, Mihai; Smythe, Elizabeth; Capasso, Federico; Joannopoulos, J

    2005-10-03

    We have calculated the optically-induced force between coupled high-Q whispering gallery modes of microsphere resonators. Attractive and repulsive forces are found, depending whether the bi-sphere mode is symmetric or antisymmetric. The magnitude of the force is linearly proportional to the total power in the spheres and consequently linearly enhanced by Q. Forces on the order of 100 nN are found for Q=108, large enough to cause displacements in the range of 1mum when the sphere is attached to a fiber stem with spring constant 0.004 N/m.

  20. Compact, lower-power-consumption wavelength tunable laser fabricated with silicon photonic-wire waveguide micro-ring resonators.

    PubMed

    Chu, Tao; Fujioka, Nobuhide; Ishizaka, Masashige

    2009-08-03

    A wavelength tunable laser with an SOA and external double micro-ring resonator, which is fabricated with silicon photonic-wire waveguides, is demonstrated. To date, it is the first wavelength tunable laser fabricated with silicon photonic technology. The device is ultra compact, and its external resonator footprint is 700 x 450 microm, which is about 1/25 that of conventional tunable lasers fabricated with SiON waveguides. The silicon resonator shows a wide tuning range covering the C or L bands for DWDM optical communication. We obtained a maximum tuning span of 38 nm at a tuning power consumption of 26 mW, which is about 1/8 that of SiON-type resonators.

  1. High-Q Superconducting Coplanar Waveguide Resonators for Integration into Molecule Ion Traps

    DTIC Science & Technology

    2010-05-01

    quality factor. We fabricated the resonators as two dimensional coplanar waveguides in niobium on R-plane sapphire using optical lithography. Resist was...patterned on the niobium using optical lithography, developed then reactive-ion etched to transfer the pattern into the niobium . The resonators were...resonators as two dimensional coplanar waveguides in niobium on R-plane sapphire using optical lithography. Resist was patterned on the niobium using

  2. Design Considerations for High-Q Bandpass Microwave Oscillator Sensors Based Upon Resonant Amplification

    SciTech Connect

    Jones, Anthony M.; Kelly, James F.; Tedeschi, Jonathan R.; McCloy, John S.

    2014-06-23

    A series of microwave resonant oscillator sensors were designed and characterized using bandpass planar and volumetric electrical resonators having loaded quality factor (Q) values in the range of 2 to 20. The use of these resonators in positive feedback circuits yielded sensor Q-factors of up to 2 x 107, demonstrating Q-factor amplifications on the order of 106. It is shown that the Q-factor amplification can be increased in a positive feedback system through the selection of feedback loop group delay, allowing use of resonators with lower Qstat values. A low-frequency electromagnetic interference sensing application is demonstrated for two resonant oscillator configurations, showing considerable frequency sensitivity to 45 kHz emitters.

  3. High-Q nested resonator in an actively stabilized optomechanical cavity

    NASA Astrophysics Data System (ADS)

    Buters, F. M.; Heeck, K.; Eerkens, H. J.; Weaver, M. J.; Luna, F.; de Man, S.; Bouwmeester, D.

    2017-03-01

    Experiments involving micro- and nanomechanical resonators need to be carefully designed to reduce mechanical environmental noise. A small scale on-chip approach is to add a resonator to the system as a mechanical low-pass filter. However, the inherent low frequency of the low-pass filter causes the system to be easily excited mechanically. We solve this problem by applying active feedback to the resonator, thereby minimizing the motion with respect to the front mirror of an optomechanical cavity. Not only does this method actively stabilize the cavity length but it also retains the on-chip vibration isolation.

  4. Radio frequency spectral characterization and model parameters extraction of high Q optical resonators

    PubMed Central

    Abdallah, Zeina; Boucher, Yann G.; Fernandez, Arnaud; Balac, Stéphane; Llopis, Olivier

    2016-01-01

    A microwave domain characterization approach is proposed to determine the properties of high quality factor optical resonators. This approach features a very high precision in frequency and aims to acquire a full knowledge of the complex transfer function (amplitude and phase) characterizing an optical resonator using a microwave vector network analyzer. It is able to discriminate between the different coupling regimes, from the under-coupling to the selective amplification, and it is used together with a model from which the main resonator parameters are extracted, i.e. coupling factor, intrinsic losses, phase slope, intrinsic and external quality factor. PMID:27251460

  5. Demonstration of high-Q mid-infrared chalcogenide glass-on-silicon resonators.

    PubMed

    Lin, Hongtao; Li, Lan; Zou, Yi; Danto, Sylvain; Musgraves, J David; Richardson, Kathleen; Kozacik, Stephen; Murakowski, Maciej; Prather, Dennis; Lin, Pao T; Singh, Vivek; Agarwal, Anu; Kimerling, Lionel C; Hu, Juejun

    2013-05-01

    We demonstrated high-index-contrast, waveguide-coupled As2Se3 chalcogenide glass resonators monolithically integrated on silicon fabricated using optical lithography and a lift-off process. The resonators exhibited a high intrinsic quality factor of 2×10(5) at 5.2 μm wavelength, which is among the highest values reported in on-chip mid-infrared (mid-IR) photonic devices. The resonator can serve as a key building block for mid-IR planar photonic circuits.

  6. Simultaneous electrical and optical readout of graphene-coated high Q silicon nitride resonators

    NASA Astrophysics Data System (ADS)

    Adiga, V. P.; De Alba, R.; Storch, I. R.; Yu, P. A.; Ilic, B.; Barton, R. A.; Lee, S.; Hone, J.; McEuen, P. L.; Parpia, J. M.; Craighead, H. G.

    2013-09-01

    Resonant mechanics of high quality factor (Q) graphene coated silicon nitride devices have been explored using optical and electrical transduction schemes. With the addition of the graphene layer, we retain the desirable mechanical properties of silicon nitride but utilize the electrical and optical properties of graphene to transduce and tune the resonant motion by both optical and electrical means. By positioning the graphene-on-silicon-nitride drums in a tunable optical cavity, we observe position dependent damping and resonant frequency control of the devices due to optical absorption by graphene.

  7. High-Q silicon-on-insulator optical rib waveguide racetrack resonators

    NASA Astrophysics Data System (ADS)

    Kiyat, Isa; Aydinli, Atilla; Dagli, Nadir

    2005-03-01

    In this work, detailed design and realization of high quality factor (Q) racetrack resonators based on silicon-on-insulator rib waveguides are presented. Aiming to achieve critical coupling, suitable waveguide geometry is determined after extensive numerical studies of bending loss. The final design is obtained after coupling factor calculations and estimation of propagation loss. Resonators with quality factors (Q) as high as 119000 has been achieved, the highest Q value for resonators based on silicon-on-insulator rib waveguides to date with extinction ratios as large as 12 dB.

  8. Monolithic integration of high-Q wedge resonators with vertically coupled waveguides

    NASA Astrophysics Data System (ADS)

    Ramiro-Manzano, Fernando; Prtljaga, Nikola; Pavesi, Lorenzo; Pucker, Georg; Ghulinyan, Mher

    2013-05-01

    Typical UHQ resonators, microspheres and microtoroids, lack the possibility of integration into lightwave circuits due to their planarity constrains. In this context, CMOS-compatible alternatives in the form of wedge resonators have been proposed. However, the mode retraction from the wedge cavity inhibits the possibility to side couple with integrated waveguides and therefore, halts the full integration within a planar lightwave circuit. In this work, we propose and demonstrate experimentally the complete integration of wedge resonators with vertically coupled dielectric bus waveguides. This coupling scheme permits to use arbitrary gaps, geometries and materials, enables simplified and precise control of the light injection into the cavity and opens the door to an industrial mass-fabrication of UHQ resonators.

  9. Selective excitation of high-Q resonant modes in a bottle/quasi-cylindrical microresonator

    NASA Astrophysics Data System (ADS)

    Dong, Yongchao; Jin, Xueying; Wang, Keyi

    2016-08-01

    We fabricate a bottle/quasi-cylindrical microresonator by using a fusion splicer. This method does not require a real-time control of the translation stages and can easily fabricate a resonator with expected size and shape. Selective excitation of whispering gallery modes (WGMs) in the resonator is realized with a fiber taper coupled at various positions of the resonator along the bottle axis. Most importantly, we obtain a clean and regular spectrum with very high quality factor (Q) modes up to 3.1×107 in the quasi-cylindrical region of the resonator. Moreover, we package the coupling system into a whole device that can be moved freely. The vibration performance tests of the packaged device show that the coupling system with the taper coupled at the quasi-cylindrical region has a remarkable anti-vibration ability. The portability and robustness of the device make it attractive in practical applications.

  10. High Q silica microbubble resonators fabricated by heating a pressurized glass capillary

    NASA Astrophysics Data System (ADS)

    Yu, Zhe; Liu, Tiegen; Jiang, Junfeng; Liu, Kun; Chen, Wenjie; Zhang, Xuezhi; Lin, Xujun; Liu, Wenhui

    2014-11-01

    Microbubble resonators combine the unique properties of whispering gallery mode resonators with the capability of integrated microfluidics. The microbubble resonator is fabricated by heating the tapered tip of a pressurized glass capillary with oxyhydrogen flame. Firstly, a microtube with a diameter of 250um is stretched under heating of oxyhydrogen flame, the heating zone length is set to be 20mm and the length of stretch is set to be 7000um.Then nitrogen will be pumped in to the tapered microtube with the pressure of 0.1Mpa, the tapered tip will be heated by the oxyhydrogen flame continuously until a microbubble forms. An optical fiber taper with a diameter of 2 um, fabricated by stretching a single-mode optical fiber under flame was brought in contact with the microbubble to couple the light from a 1550nm tunable diode laser into the whispering gallery mode. The microbubble resonator has a Q factors up to 1.5 × 107 around 1550nm. Different concentrations of ethanol solution (from 5% to 30%) are filled into it in order to test the refractive index sensing capabilities of such resonator, which shows a sensitivity of 82nm/RIU.

  11. Extremely high Q-factor mechanical modes in quartz bulk acoustic wave resonators at millikelvin temperature

    SciTech Connect

    Goryachev, M.; Creedon, D. L.; Ivanov, E. N.; Tobar, M. E.; Galliou, S.; Bourquin, R.

    2014-12-04

    We demonstrate that Bulk Acoustic Wave (BAW) quartz resonator cooled down to millikelvin temperatures are excellent building blocks for hybrid quantum systems with extremely long coherence times. Two overtones of the longitudinal mode at frequencies of 15.6 and 65.4 MHz demonstrate a maximum f.Q product of 7.8×10{sup 16} Hz. With this result, the Q-factor in such devices near the quantum ground state can be four orders of magnitude better than previously attained in other mechanical systems. Tested quartz resonators possess the ultra low acoustic losses crucial for electromagnetic cooling to the phonon ground state.

  12. Ultralow loss, high Q, four port resonant couplers for quantum optics and photonics.

    PubMed

    Rokhsari, H; Vahala, K J

    2004-06-25

    We demonstrate a low-loss, optical four port resonant coupler (add-drop geometry), using ultrahigh Q (>10(8)) toroidal microcavities. Different regimes of operation are investigated by variation of coupling between resonator and fiber taper waveguides. As a result, waveguide-to-waveguide power transfer efficiency of 93% (0.3 dB loss) and nonresonant insertion loss of 0.02% (<0.001 dB) for narrow bandwidth (57 MHz) four port couplers are achieved in this work. The combination of low-loss, fiber compatibility, and wafer-scale design would be suitable for a variety of applications ranging from quantum optics to photonic networks.

  13. High-Q photonic resonators and electro-optic coupling using silicon-on-lithium-niobate

    NASA Astrophysics Data System (ADS)

    Witmer, Jeremy D.; Valery, Joseph A.; Arrangoiz-Arriola, Patricio; Sarabalis, Christopher J.; Hill, Jeff T.; Safavi-Naeini, Amir H.

    2017-04-01

    Future quantum networks, in which superconducting quantum processors are connected via optical links, will require microwave-to-optical photon converters that preserve entanglement. A doubly-resonant electro-optic modulator (EOM) is a promising platform to realize this conversion. Here, we present our progress towards building such a modulator by demonstrating the optically-resonant half of the device. We demonstrate high quality (Q) factor ring, disk and photonic crystal resonators using a hybrid silicon-on-lithium-niobate material system. Optical Q factors up to 730,000 are achieved, corresponding to propagation loss of 0.8 dB/cm. We also use the electro-optic effect to modulate the resonance frequency of a photonic crystal cavity, achieving a electro-optic modulation coefficient between 1 and 2 pm/V. In addition to quantum technology, we expect that our results will be useful both in traditional silicon photonics applications and in high-sensitivity acousto-optic devices.

  14. High-Q photonic resonators and electro-optic coupling using silicon-on-lithium-niobate

    PubMed Central

    Witmer, Jeremy D.; Valery, Joseph A.; Arrangoiz-Arriola, Patricio; Sarabalis, Christopher J.; Hill, Jeff T.; Safavi-Naeini, Amir H.

    2017-01-01

    Future quantum networks, in which superconducting quantum processors are connected via optical links, will require microwave-to-optical photon converters that preserve entanglement. A doubly-resonant electro-optic modulator (EOM) is a promising platform to realize this conversion. Here, we present our progress towards building such a modulator by demonstrating the optically-resonant half of the device. We demonstrate high quality (Q) factor ring, disk and photonic crystal resonators using a hybrid silicon-on-lithium-niobate material system. Optical Q factors up to 730,000 are achieved, corresponding to propagation loss of 0.8 dB/cm. We also use the electro-optic effect to modulate the resonance frequency of a photonic crystal cavity, achieving a electro-optic modulation coefficient between 1 and 2 pm/V. In addition to quantum technology, we expect that our results will be useful both in traditional silicon photonics applications and in high-sensitivity acousto-optic devices. PMID:28406177

  15. High-Q photonic resonators and electro-optic coupling using silicon-on-lithium-niobate.

    PubMed

    Witmer, Jeremy D; Valery, Joseph A; Arrangoiz-Arriola, Patricio; Sarabalis, Christopher J; Hill, Jeff T; Safavi-Naeini, Amir H

    2017-04-13

    Future quantum networks, in which superconducting quantum processors are connected via optical links, will require microwave-to-optical photon converters that preserve entanglement. A doubly-resonant electro-optic modulator (EOM) is a promising platform to realize this conversion. Here, we present our progress towards building such a modulator by demonstrating the optically-resonant half of the device. We demonstrate high quality (Q) factor ring, disk and photonic crystal resonators using a hybrid silicon-on-lithium-niobate material system. Optical Q factors up to 730,000 are achieved, corresponding to propagation loss of 0.8 dB/cm. We also use the electro-optic effect to modulate the resonance frequency of a photonic crystal cavity, achieving a electro-optic modulation coefficient between 1 and 2 pm/V. In addition to quantum technology, we expect that our results will be useful both in traditional silicon photonics applications and in high-sensitivity acousto-optic devices.

  16. High sensitivity dual microring sensor based on intensity detection

    NASA Astrophysics Data System (ADS)

    Yi, H.; Citrin, D. S.; Zhou, Z.

    2010-12-01

    By employing the enhanced phase transfer of single microring resonator, the enhanced intensity sensing is obtained based on the dual microring resonator with coupled mode theory. The two times higher sensitivity than the conventional microring sensor is demonstrated based on the FDTD simulation.

  17. Energy correlations of photon pairs generated by a silicon microring resonator probed by Stimulated Four Wave Mixing

    PubMed Central

    Grassani, Davide; Simbula, Angelica; Pirotta, Stefano; Galli, Matteo; Menotti, Matteo; Harris, Nicholas C.; Baehr-Jones, Tom; Hochberg, Michael; Galland, Christophe; Liscidini, Marco; Bajoni, Daniele

    2016-01-01

    Compact silicon integrated devices, such as micro-ring resonators, have recently been demonstrated as efficient sources of quantum correlated photon pairs. The mass production of integrated devices demands the implementation of fast and reliable techniques to monitor the device performances. In the case of time-energy correlations, this is particularly challenging, as it requires high spectral resolution that is not currently achievable in coincidence measurements. Here we reconstruct the joint spectral density of photons pairs generated by spontaneous four-wave mixing in a silicon ring resonator by studying the corresponding stimulated process, namely stimulated four wave mixing. We show that this approach, featuring high spectral resolution and short measurement times, allows one to discriminate between nearly-uncorrelated and highly-correlated photon pairs. PMID:27032688

  18. Broadband microwave photonic phase shifter based on a feedback-coupled microring resonator with small radio frequency power variations.

    PubMed

    Tang, Jian; Li, Ming; Sun, Shuqian; Li, Zhiyong; Li, Wei; Zhu, Ninghua

    2016-10-15

    An on-chip microwave photonic phase shifter based on an electrically tunable feedback-coupled microring resonator (FCMR) is proposed and experimentally demonstrated. By properly adjusting the voltage applied on the FCMR, the transmission spectrum with different optical extinction ratios is realized while the phase shift range remains almost unchanged. This proposal solves the conflict between the large range of phase shift and small radio frequency (RF) power variation in the ring-resonator-based microwave photonics phase shifter. Finally, a microwave photonic phase shifter with phase tuning of over 172 deg from 20 to 30 GHz is obtained, and the RF power variation can be compressed less than 5 dB under a certain status tuned by the bias voltage.

  19. Energy correlations of photon pairs generated by a silicon microring resonator probed by Stimulated Four Wave Mixing.

    PubMed

    Grassani, Davide; Simbula, Angelica; Pirotta, Stefano; Galli, Matteo; Menotti, Matteo; Harris, Nicholas C; Baehr-Jones, Tom; Hochberg, Michael; Galland, Christophe; Liscidini, Marco; Bajoni, Daniele

    2016-04-01

    Compact silicon integrated devices, such as micro-ring resonators, have recently been demonstrated as efficient sources of quantum correlated photon pairs. The mass production of integrated devices demands the implementation of fast and reliable techniques to monitor the device performances. In the case of time-energy correlations, this is particularly challenging, as it requires high spectral resolution that is not currently achievable in coincidence measurements. Here we reconstruct the joint spectral density of photons pairs generated by spontaneous four-wave mixing in a silicon ring resonator by studying the corresponding stimulated process, namely stimulated four wave mixing. We show that this approach, featuring high spectral resolution and short measurement times, allows one to discriminate between nearly-uncorrelated and highly-correlated photon pairs.

  20. Molybdenum-rhenium alloy based high-Q superconducting microwave resonators

    SciTech Connect

    Singh, Vibhor Schneider, Ben H.; Bosman, Sal J.; Merkx, Evert P. J.; Steele, Gary A.

    2014-12-01

    Superconducting microwave resonators (SMRs) with high quality factors have become an important technology in a wide range of applications. Molybdenum-Rhenium (MoRe) is a disordered superconducting alloy with a noble surface chemistry and a relatively high transition temperature. These properties make it attractive for SMR applications, but characterization of MoRe SMR has not yet been reported. Here, we present the fabrication and characterization of SMR fabricated with a MoRe 60–40 alloy. At low drive powers, we observe internal quality-factors as high as 700 000. Temperature and power dependence of the internal quality-factors suggest the presence of the two level systems from the dielectric substrate dominating the internal loss at low temperatures. We further test the compatibility of these resonators with high temperature processes, such as for carbon nanotube chemical vapor deposition growth, and their performance in the magnetic field, an important characterization for hybrid systems.

  1. Neutral Pion Electroproduction in the Resonance Region at High $Q^2$

    SciTech Connect

    Villano, A N; Bosted, P E; Connell, S H; Dalton, M M; Jones, M K; Adams, G S; Afanasev, A; Ahmidouch, A; Angelescu, T; Arrington, J; Asaturyan, R; Baker, O K; Benmouna, N; Berman, B L; Breuer, H; Christy, M E; Cui, Y; Danagoulian, S; Day, D; Dodario, T; Dunne, J A; Dutta, D; El Khayari, N; Elliot, B; Ent, R; Fenker, H C; Frolov, V V; Gan, L; Gaskell, D; Gasparian, A; Grullon, S; Hafidi, K; Hinton, W; Holt, R J; Huber, G M; Hungerford, E; Joo, K; Kalantarians, N; Keppel, C E; Kinney, E R; Kubarovsky, V; Li, Y; Liang, Y; Lu, M; Lung, A; Mack, D; Malace, S; Markowitz, P; McKee, P; Meekins, D G; Mkrtchhyan, H; Napolitano, J; Niculescu, G; Niculescu, I; Opper, A K; Pamela, P; Potterveld, D H; Reimer, Paul E; Reinhold, J; Roche, J; Rock, S E; Schulte, E; Segbefia, E; Smith, C; Smith, G R

    2009-09-01

    The process $ep \\to e^{\\prime}p^{\\prime}\\pi^0$ has been measured at $Q^2$ = 6.4 and 7.7 \\ufourmomts in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center of mass frame considering the process $\\gamma^{\\ast}p \\to p^{\\prime}\\pi^0$. Various details relating to the background subtractions, radiative corrections and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well known $\\Delta(1232)$ resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios $R_{EM}$ and $R_{SM}$ along with the magnetic transition form factor $G_M^{\\ast}$. It is found that the rapid fall off of the $\\Delta(1232)$ contribution continues into this region of momentum transfer and that other resonances

  2. Characterization of the evanescent field profile and bound mass sensitivity of a label-free silicon photonic microring resonator biosensing platform.

    PubMed

    Luchansky, Matthew S; Washburn, Adam L; Martin, Teresa A; Iqbal, Muzammil; Gunn, L Cary; Bailey, Ryan C

    2010-12-15

    Silicon photonic microring resonators have emerged as a sensitive and highly multiplexed platform for real-time biomolecule detection. Herein, we profile the evanescent decay of device sensitivity towards molecular binding as a function of distance from the microring surface. By growing multilayers of electrostatically bound polymers extending from the sensor surface, we are able to empirically determine that the evanescent field intensity is characterized by a 1/e response decay distance of 63 nm. We then applied this knowledge to study the growth of biomolecular assemblies consisting of alternating layers of biotinylated antibody and streptavidin, which follow a more complex growth pattern. Additionally, by monitoring the shift in microring resonance wavelength upon the deposition of a radioactively labeled protein, the mass sensitivity of the ring resonator platform was determined to be 14.7±6.7 [pg/mm(2)]/Δpm. By extrapolating to the instrument noise baseline, the mass/area limit of detection is found to be 1.5±0.7 pg/mm(2). Taking the small surface area of the microring sensor into consideration, this value corresponds to an absolute mass detection limit of 125 ag (i.e. 0.8 zmol of IgG), demonstrating the remarkable sensitivity of this promising label-free biomolecular sensing platform.

  3. Dispersion engineering of thick high-Q silicon nitride ring-resonators via atomic layer deposition.

    PubMed

    Riemensberger, Johann; Hartinger, Klaus; Herr, Tobias; Brasch, Victor; Holzwarth, Ronald; Kippenberg, Tobias J

    2012-12-03

    We demonstrate dispersion engineering of integrated silicon nitride based ring resonators through conformal coating with hafnium dioxide deposited on top of the structures via atomic layer deposition. Both, magnitude and bandwidth of anomalous dispersion can be significantly increased. The results are confirmed by high resolution frequency-comb-assisted-diode-laser spectroscopy and are in very good agreement with the simulated modification of the mode spectrum.

  4. Tapered Glass-Fiber Microspike: High-Q Flexural Wave Resonator and Optically Driven Knudsen Pump

    NASA Astrophysics Data System (ADS)

    Pennetta, Riccardo; Xie, Shangran; Russell, Philip St. J.

    2016-12-01

    Appropriately designed optomechanical devices are ideal for making ultra-sensitive measurements. Here we report a fused-silica microspike that supports a flexural resonance with a quality factor greater than 100 000 at room temperature in vacuum. Fashioned by tapering single-mode fiber (SMF), it is designed so that the core-guided optical mode in the SMF evolves adiabatically into the fundamental mode of the air-glass waveguide at the tip. The very narrow mechanical linewidth (20 mHz) makes it possible to measure extremely small changes in resonant frequency. In a vacuum chamber at low pressure, the weak optical absorption of the glass is sufficient to create a temperature gradient along the microspike, which causes it to act as a microscopic Knudsen pump, driving a flow of gas molecules towards the tip where the temperature is highest. The result is a circulating molecular flow within the chamber. Momentum exchange between the vibrating microspike and the flowing molecules causes an additional restoring force that can be measured as a tiny shift in the resonant frequency. The effect is strongest when the mean free path of the gas molecules is comparable with the dimensions of the vacuum chamber. The system offers a novel means of monitoring the behavior of weakly absorbing optomechanical sensors operating in vacuum.

  5. Electroproduction of 0̂ and η in the resonance region at high Q^2 with CLAS

    NASA Astrophysics Data System (ADS)

    Ungaro, Maurizio; Joo, Kyungseon

    2009-10-01

    We report the analysis of exclusive single 0̂ and η electroproduction in the resonance region at Jefferson Lab in the Q^2 range 2 to 6 GeV^2/c^2. A longitudinally polarized 5.75 GeV electron beam was incident on a 5 cm long liquid Hydrogen target. The CLAS spectrometer at Jefferson Lab was used to detect the final state particles. The goal of this analysis is to extract 0̂ and η c.m. differential cross sections over the entire 4π c.m. solid angle, up to W=2 GeV, and their beam spin asymmetries.

  6. Ultra-high-Q thin-silicon nitride strip-loaded ring resonators.

    PubMed

    Stefan, L; Bernard, M; Guider, R; Pucker, G; Pavesi, L; Ghulinyan, M

    2015-07-15

    We report on the design, fabrication, and characterization of thin Si3N4 ultra-high-quality (UHQ) factor ring resonators monolithically integrated on a silicon chip. The devices are based on a strip-loaded configuration and operate at both near-infrared (NIR) and third-telecom wavelengths. This approach allows us to use a guiding Si3N4 core that is one order of magnitude thinner than what has been reported in the past for obtaining similar device performances. Our strip-loaded devices benefit from the absence of physically etched lateral boundaries to show minute light scattering and, therefore, reducing significantly scattering-related losses. Consequently, UHQs of 3.7×10(6) in the NIR and high-quality factors of up to 9×10(5) in the C-band were measured for the guiding material thickness of 80 nm and 115 nm, respectively. These first results are subject to further improvements that may allow employing strip-loaded resonators in nonlinear frequency conversion or quantum computing schemes within the desired spectral range provided by the material transparency.

  7. Neutral pion electroproduction in the resonance region at high Q{sup 2}.

    SciTech Connect

    Villano, A. N.; Stoler, P.; Bosted, P. E.; Connell, S. H.; Dalton, M. M.; Arrington, J.; Hafidi, K.; Holt, R. J.; Schulte, E.; Reimer, P. E.; Zheng, X.; Physics; Rensselaer Polytechnic Inst.; Thomas Jefferson National Accelerator Facility; Univ. of the Johannesburg; Univ. of the Witwatersrand

    2009-09-01

    The process ep {yields} ep{pi}{sup 0} has been measured at Q{sup 2} = 6.4 and 7.7 (GeV/c{sup 2}){sup 2} in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center-of-mass frame considering the process {gamma}*p {yields} p{pi}{sup 0}. Various details relating to the background subtractions, radiative corrections, and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well-known {Delta}(1232) resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios R{sub EM} and R{sub SM} along with the magnetic transition form factor G*{sub M}. It is found that the rapid falloff of the {Delta}(1232) contribution continues into this region of momentum transfer and that other resonances may be making important contributions in this region.

  8. Neutral pion electroproduction in the resonance region at high Q{sup 2}

    SciTech Connect

    Villano, A. N.; Stoler, P.; Kubarovsky, V.; Adams, G. S.; Napolitano, J.; Bosted, P. E.; Jones, M. K.; Ent, R.; Fenker, H. C.; Gaskell, D.; Lung, A.; Mack, D.; Meekins, D. G.; Roche, J.; Smith, G. R.; Wojtsekhowski, B.; Wood, S. A.; Connell, S. H.; Dalton, M. M.; Ahmidouch, A.

    2009-09-15

    The process ep{yields}ep{pi}{sup 0} has been measured at Q{sup 2}=6.4 and 7.7 (GeV/c{sup 2}){sup 2} in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center-of-mass frame considering the process {gamma}*p{yields}p{pi}{sup 0}. Various details relating to the background subtractions, radiative corrections, and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well-known {delta}(1232) resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios R{sub EM} and R{sub SM} along with the magnetic transition form factor G{sub M}*. It is found that the rapid falloff of the {delta}(1232) contribution continues into this region of momentum transfer and that other resonances may be making important contributions in this region.

  9. Reduction of Simulation Times for High-Q Structures using the Resonance Equation

    DOE PAGES

    Hall, Thomas Wesley; Bandaru, Prabhakar R.; Rees, Daniel Earl

    2015-11-17

    Simulating steady state performance of high quality factor (Q) resonant RF structures is computationally difficult for structures with sizes on the order of more than a few wavelengths because of the long times (on the order of ~ 0.1 ms) required to achieve steady state in comparison with maximum time step that can be used in the simulation (typically, on the order of ~ 1 ps). This paper presents analytical and computational approaches that can be used to accelerate the simulation of the steady state performance of such structures. The basis of the proposed approach is the utilization of amore » larger amplitude signal at the beginning to achieve steady state earlier relative to the nominal input signal. Finally, the methodology for finding the necessary input signal is then discussed in detail, and the validity of the approach is evaluated.« less

  10. Single electron tunnelling through high-Q single-wall carbon nanotube NEMS resonators

    NASA Astrophysics Data System (ADS)

    Hüttel, A. K.; Meerwaldt, H. B.; Steele, G. A.; Poot, M.; Witkamp, B.; Kouwenhoven, L. P.; van der Zant, H. S. J.

    2010-12-01

    By first lithographically fabricating contact electrodes and then as last step growing carbon nanotubes with chemical vapour deposition across the ready-made chip, many potential contamination mechanisms for nanotube devices can be avoided. Combining this with pre-defined trenches on the chip, such that the nanotubes are freely suspended above the substrate, enables the formation of highly regular electronic systems. We show that, in addition, such suspended ultra-clean nanotubes provide excellent high-frequency and low-dissipation mechanical resonators. The motion detection mechanism of our experiment is discussed, and we measure the effect of Coulomb blockade and the back-action of single electron tunneling on the mechanical motion. In addition data on the mechanical higher modes is presented.

  11. Reduction of Simulation Times for High-Q Structures using the Resonance Equation

    SciTech Connect

    Hall, Thomas Wesley; Bandaru, Prabhakar R.; Rees, Daniel Earl

    2015-11-17

    Simulating steady state performance of high quality factor (Q) resonant RF structures is computationally difficult for structures with sizes on the order of more than a few wavelengths because of the long times (on the order of ~ 0.1 ms) required to achieve steady state in comparison with maximum time step that can be used in the simulation (typically, on the order of ~ 1 ps). This paper presents analytical and computational approaches that can be used to accelerate the simulation of the steady state performance of such structures. The basis of the proposed approach is the utilization of a larger amplitude signal at the beginning to achieve steady state earlier relative to the nominal input signal. Finally, the methodology for finding the necessary input signal is then discussed in detail, and the validity of the approach is evaluated.

  12. Electroproduction of 0̂ and η in the resonance region at high Q^2 with CLAS

    NASA Astrophysics Data System (ADS)

    Ungaro, Maurizio; Joo, Kyungseon

    2010-02-01

    An extensive program is underway at Jefferson Lab to study the eletromagnetic excitations of baryon states. We report the analysis of exclusive single 0̂ and η electroproduction in the resonance region at Jefferson Lab in the Q^2 range of 2 to 6 GeV^2/c^2. A longitudinally polarized 5.75 GeV electron beam was incident on a 5 cm long liquid Hydrogen target. The CLAS spectrometer at Jefferson Lab was used to detect the final state particles. The average beam polarization was 70%. The data was taken between October 2001 and January 2002. Preliminary differential cross sections over the entire 4π c.m. solid angle will be presented, along with beam spin asymmetries. Preliminary structure functions will be shown. This high precision measurement will allow us to access the structure and dynamics of nucleon excitations with masses up to 2 GeV. )

  13. Electroproduction of π0 in the resonance region at high Q2 with CLAS

    NASA Astrophysics Data System (ADS)

    Ungaro, Maurizio; Joo, Kyungseon; CLAS Collaboration

    2014-09-01

    An extensive program is underway at Jefferson Lab to study the eletromagnetic excitations of baryon states. We report the analysis of exclusive single π0 electroproduction in the resonance region at Jefferson Lab in the Q2 range of 2 to 6 GeV2 /c2 . A longitudinally polarized 5 . 75 GeV electron beam was incident on a 5 cm long liquid Hydrogen target. The CLAS spectrometer at Jefferson Lab was used to detect the final state particles. The data was taken between October 2001 and January 2002. Preliminary results for differential cross sections over the entire 4 π c .m . solid angle will be presented. This high precision measurement will allow us to access the structure and dynamics of nucleon excitations with masses up to 2 GeV .

  14. Electroproduction of π0 in the resonance region at high Q2 with CLAS

    NASA Astrophysics Data System (ADS)

    Ungaro, Maurizio; Joo, Kyungseon; CLAS Collaboration

    2011-04-01

    An extensive program is underway at Jefferson Lab to study the eletromagnetic excitations of baryon states. We report the analysis of exclusive single π0 and η electroproduction in the resonance region at Jefferson Lab in the Q2 range of 2 to 6 GeV2 /c2 . A longitudinally polarized 5 . 75 GeV electron beam was incident on a 5 cm long liquid Hydrogen target. The CLAS spectrometer at Jefferson Lab was used to detect the final state particles. The average beam polarization was 70 % . The data was taken between October 2001 and January 2002. Preliminary results for differential cross sections and beam spin asymmetries over the entire 4 π c . m . solid angle will be presented. This high precision measurement will allow us to access the structure and dynamics of nucleon excitations with masses up to 2 GeV .

  15. High-Q AlN/SiO2 symmetric composite thin film bulk acoustic wave resonators.

    PubMed

    Artieda, Alvaro; Muralt, Paul

    2008-11-01

    High-Q, bulk acoustic wave composite resonators based on a symmetric layer sequence of SiO(2)-AlN-SiO(2) sandwiched between electrodes have been developed. Acoustic isolation was achieved by means of deep silicon etching to obtain membrane type thin film bulk acoustic wave resonators (TFBARs). Three different device versions were investigated. The SiO(2) film thicknesses were varied (0 nm, 70 nm, 310 nm, and 770 nm) while the piezoelectric AlN film had a constant thickness of 1.2 microm. The sputter-deposited AlN film grown on the amorphous, sputter-deposited SiO(2) layer exhibited a d(33,f) of 4.0 pm/V. Experimental results of quality factors (Q) and coupling coefficients (k(t)(2)) are in agreement with finite element calculations. A Q of 2000 is observed for the first harmonic of the 310 nm oxide devices. The most intense resonance of the 770 nm oxide device is the third harmonic reaching Q factors of 1450. The temperature drift reveals the impact of the SiO(2) layers, which is more pronounced on the first harmonic, reducing the TCF to 4 ppm/K for the 3rd harmonic of the 310 nm oxide devices.

  16. High-Q microsphere resonators for angular velocity sensing in gyroscopes

    SciTech Connect

    An, Panlong; Zheng, Yongqiu; Yan, Shubin Xue, Chenyang Liu, Jun; Wang, Wanjun

    2015-02-09

    A resonator gyroscope based on the Sagnac effect is proposed using a core unit that is generated by water-hydrogen flame melting. The relationship between the quality factor Q and diameter D is revealed. The Q factor of the spectral lines of the microsphere cavity coupling system, which uses tapered fibers, is found to be 10{sup 6} or more before packaging with a low refractive curable ultraviolet polymer, although it drops to approximately 10{sup 5} after packaging. In addition, a rotating test platform is built, and the transmission spectrum and discriminator curves of a microsphere cavity with Q of 3.22×10{sup 6} are measured using a semiconductor laser (linewidth less than 1 kHz) and a real-time proportional-integral circuit tracking and feedback technique. Equations fitting the relation between the voltage and angular rotation rate are obtained. According to the experimentally measured parameters, the sensitivity of the microsphere-coupled system can reach 0.095{sup ∘}/s.

  17. The influence of thermal and free carrier dispersion effects on all-optical wavelength conversion in a silicon racetrack-shaped microring resonator

    NASA Astrophysics Data System (ADS)

    Wang, Zhaolu; Liu, Hongjun; Sun, Qibing; Huang, Nan; Li, Shaopeng; Han, Jing

    2016-07-01

    We experimentally demonstrate ultra-low pump power wavelength conversion based on four-wave mixing in a silicon racetrack-shaped microring resonator. When the pump and signal are located at the resonance wavelengths, wavelength conversion with a pump power of only 1 mW can be realized in this microring resonator because of the resonant enhancement of the device. However, saturation of the conversion efficiency occurs because of the shift of the resonance peak, which is caused by the change of the effective refractive index induced by a combination of thermal and free carrier dispersion effects, and it is demonstrated that the thermal effect is the leading-order factor for the change of the refractive index. The maximum conversion efficiency of  -21 dB is obtained when the pump power is less than 12 mW. This ultra-low-power on-chip wavelength convertor based on a silicon microring resonator can find important potential applications in highly integrated optical circuits for all-optical signal processing.

  18. All-optical differential equation solver with constant-coefficient tunable based on a single microring resonator

    PubMed Central

    Yang, Ting; Dong, Jianji; Lu, Liangjun; Zhou, Linjie; Zheng, Aoling; Zhang, Xinliang; Chen, Jianping

    2014-01-01

    Photonic integrated circuits for photonic computing open up the possibility for the realization of ultrahigh-speed and ultra wide-band signal processing with compact size and low power consumption. Differential equations model and govern fundamental physical phenomena and engineering systems in virtually any field of science and engineering, such as temperature diffusion processes, physical problems of motion subject to acceleration inputs and frictional forces, and the response of different resistor-capacitor circuits, etc. In this study, we experimentally demonstrate a feasible integrated scheme to solve first-order linear ordinary differential equation with constant-coefficient tunable based on a single silicon microring resonator. Besides, we analyze the impact of the chirp and pulse-width of input signals on the computing deviation. This device can be compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may motivate the development of integrated photonic circuits for optical computing. PMID:24993440

  19. Optical solver for a system of ordinary differential equations based on an external feedback assisted microring resonator.

    PubMed

    Hou, Jie; Dong, Jianji; Zhang, Xinliang

    2017-06-15

    Systems of ordinary differential equations (SODEs) are crucial for describing the dynamic behaviors in various systems such as modern control systems which require observability and controllability. In this Letter, we propose and experimentally demonstrate an all-optical SODE solver based on the silicon-on-insulator platform. We use an add/drop microring resonator to construct two different ordinary differential equations (ODEs) and then introduce two external feedback waveguides to realize the coupling between these ODEs, thus forming the SODE solver. A temporal coupled mode theory is used to deduce the expression of the SODE. A system experiment is carried out for further demonstration. For the input 10 GHz NRZ-like pulses, the measured output waveforms of the SODE solver agree well with the calculated results.

  20. All-optical differential equation solver with constant-coefficient tunable based on a single microring resonator.

    PubMed

    Yang, Ting; Dong, Jianji; Lu, Liangjun; Zhou, Linjie; Zheng, Aoling; Zhang, Xinliang; Chen, Jianping

    2014-07-04

    Photonic integrated circuits for photonic computing open up the possibility for the realization of ultrahigh-speed and ultra wide-band signal processing with compact size and low power consumption. Differential equations model and govern fundamental physical phenomena and engineering systems in virtually any field of science and engineering, such as temperature diffusion processes, physical problems of motion subject to acceleration inputs and frictional forces, and the response of different resistor-capacitor circuits, etc. In this study, we experimentally demonstrate a feasible integrated scheme to solve first-order linear ordinary differential equation with constant-coefficient tunable based on a single silicon microring resonator. Besides, we analyze the impact of the chirp and pulse-width of input signals on the computing deviation. This device can be compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may motivate the development of integrated photonic circuits for optical computing.

  1. High performance microring resonator (MRR)-based optical filter with reduced group delay and simplified center-wavelength control

    NASA Astrophysics Data System (ADS)

    Dingel, Benjamin; Ye, Bo; Cui, Weili; Madamopoulos, Nicholas

    2013-06-01

    We present a new microring resonator (MRR)-based optical filter that takes advantage of the improvements that can be gained from cascading two (or more) MRR elements while physically using only one MRR element due to its unique looped-back configuration. This approach avoids the costly problem associated with dynamic control of matching (or aligning) the center-wavelengths coming from the two MRR elements. This new optical filter is a generalization of our previously reported filter (called LOBOUR) based on the Cascaded Over- and Under-coupling Resonator (COUR) architecture. Here, we compare the performance of our filter to four different configurations under the following criteria: (1) lower group delay (GD), and (2) simplified solution to wavelength-drift problem, (3) lower power consumption, (4) narrower linewidth, and (5) better extinction ratio (ER).

  2. Unfolding a design rule for microparticle buffering and dropping in microring-resonator-based add-drop devices.

    PubMed

    Wang, Jiawei; Poon, Andrew W

    2014-04-21

    We propose an intuitive and quantitative design rule to determine the microparticle transport processes, including buffering and dropping, on microring-resonator-based add-drop devices at cavity resonances in an integrated optofluidic chip. The design rule uses the splitting ratio, S, of the optical-field intensity at the microring feedback-arc just after the output-coupling region to that at the drop-waveguide as a figure-of-merit for particle transport to determine between particle buffering (S > 1) and dropping (S < 1). The particle transport, however, becomes probabilistic in the case that S is close to 1. The S factor thus provides a clearer physical criterion for determining the particle transport processes compared to the cavity quality (Q) factor. We experimentally investigate this design rule on four different devices with different design parameters on a silicon nitride-on-silica substrate, and show that the particle transport behaviours of 2.2 μm- and 0.8 μm-sized polystyrene particles are consistent with the S values extracted from the transmission spectra. Our numerical simulations of the four devices suggest that the S values extracted from the simulated transmission spectra are consistent with those extracted from the simulated mode-field intensity distributions. We calculate the optical force field using Maxwell stress tensor and an effective microdisk model to relate the S values to the particle transport processes. We further experimentally demonstrate the viability of the design rule by switching between deterministic particle buffering and probabilistic particle transport processes by switching the polarization modes.

  3. High-coherence semiconductor lasers based on integral high-Q resonators in hybrid Si/III-V platforms.

    PubMed

    Santis, Christos Theodoros; Steger, Scott T; Vilenchik, Yaakov; Vasilyev, Arseny; Yariv, Amnon

    2014-02-25

    The semiconductor laser (SCL) is the principal light source powering the worldwide optical fiber network. The ever-increasing demand for data is causing the network to migrate to phase-coherent modulation formats, which place strict requirements on the temporal coherence of the light source that no longer can be met by current SCLs. This failure can be traced directly to the canonical laser design, in which photons are both generated and stored in the same, optically lossy, III-V material. This leads to an excessive and large amount of noisy spontaneous emission commingling with the laser mode, thereby degrading its coherence. High losses also decrease the amount of stored optical energy in the laser cavity, magnifying the effect of each individual spontaneous emission event on the phase of the laser field. Here, we propose a new design paradigm for the SCL. The keys to this paradigm are the deliberate removal of stored optical energy from the lossy III-V material by concentrating it in a passive, low-loss material and the incorporation of a very high-Q resonator as an integral (i.e., not externally coupled) part of the laser cavity. We demonstrate an SCL with a spectral linewidth of 18 kHz in the telecom band around 1.55 μm, achieved using a single-mode silicon resonator with Q of 10(6).

  4. High-coherence semiconductor lasers based on integral high-Q resonators in hybrid Si/III-V platforms

    PubMed Central

    Santis, Christos Theodoros; Steger, Scott T.; Vilenchik, Yaakov; Vasilyev, Arseny; Yariv, Amnon

    2014-01-01

    The semiconductor laser (SCL) is the principal light source powering the worldwide optical fiber network. The ever-increasing demand for data is causing the network to migrate to phase-coherent modulation formats, which place strict requirements on the temporal coherence of the light source that no longer can be met by current SCLs. This failure can be traced directly to the canonical laser design, in which photons are both generated and stored in the same, optically lossy, III-V material. This leads to an excessive and large amount of noisy spontaneous emission commingling with the laser mode, thereby degrading its coherence. High losses also decrease the amount of stored optical energy in the laser cavity, magnifying the effect of each individual spontaneous emission event on the phase of the laser field. Here, we propose a new design paradigm for the SCL. The keys to this paradigm are the deliberate removal of stored optical energy from the lossy III-V material by concentrating it in a passive, low-loss material and the incorporation of a very high-Q resonator as an integral (i.e., not externally coupled) part of the laser cavity. We demonstrate an SCL with a spectral linewidth of 18 kHz in the telecom band around 1.55 μm, achieved using a single-mode silicon resonator with Q of 106. PMID:24516134

  5. Measurements of the refractive indices and thermo-optic coefficients of Si3N4 and SiO(x) using microring resonances.

    PubMed

    Arbabi, Amir; Goddard, Lynford L

    2013-10-01

    We present a method for determining the core and cladding refractive indices of a microring resonator from its measured quasi-transverse electric and magnetic resonant modes. We use single wavelength reflective microrings to resolve the azimuthal order ambiguity of the measured resonances. We perform accurate electromagnetic simulations to model the dependence of the resonances on geometrical and material parameters. We linearize the model and use the singular value decomposition method to find the best fit parameters for the measured data. At 1550 nm, we determine n(Si(3)N(4))=1.977±0.003 for stoichiometric silicon nitride deposited using low-pressure chemical vapor deposition (LPCVD) technique and n(SiO(x))=1.428±0.011 for plasma-enhanced chemical vapor deposition (PECVD) oxide. By measuring the temperature sensitivities of microring resonant modes with different polarizations, we find the thermo-optic coefficient of the stoichiometric silicon nitride to be dn(Si(3)N(4))/dT=(2.45±0.09)×10(-5) (RIU/°C) and the PECVD oxide to be dn(SiO(x))/dT=(0.95±0.10)×10(-5) (RIU/°C).

  6. Thermoelastic damping effect of the micro-ring resonator with irregular mass and stiffness

    NASA Astrophysics Data System (ADS)

    Kim, Jung-Hwan; Kim, Ji-Hwan

    2016-05-01

    Fundamentally, vibration characteristic is a main factor for the stability of structures. In this regard, the irregularity of mass and stiffness distributions for the structure have been an interesting issue for many years. Recently, the Micro Electro Mechanical Systems (MEMS) are developed for various applications such as gyro sensors. In the present work, in-plane vibration of micro-ring structure with multiple finite-sized imperfections is investigated. Then, the unbalance of the structure is represented using Heaviside Step Function for the inextensional modeling of the ring. Also, thermoelastic damping (TED) due to internal friction is studied based on Fourier's one-dimensional heat conduction equation using Laplace Transform. To obtain the quality-factors (Q-factors) for imperfect micro-ring, analytical solutions are calculated from governing equations of motion with TED. And then, the natural frequencies and the Q-factors are observed to separate into lower and higher modes. Additionally, the vibration mode shapes are presented, and the frequency trimming concept due to attached imperfections is investigated.

  7. On-chip multi spectral frequency standard replication by stabilizing a microring resonator to a molecular line

    NASA Astrophysics Data System (ADS)

    Zektzer, Roy; Stern, Liron; Mazurski, Noa; Levy, Uriel

    2016-07-01

    Stabilized laser lines are highly desired for myriad of applications ranging from precise measurements to optical communications. While stabilization can be obtained by using molecular or atomic absorption references, these are limited to specific frequencies. On the other hand, resonators can be used as wide band frequency references. Unfortunately, such resonators are unstable and inaccurate. Here, we propose and experimentally demonstrate a chip-scale multispectral frequency standard replication operating in the spectral range of the near IR. This is obtained by frequency locking a microring resonator (MRR) to an acetylene absorption line. The MRR consists of a Si3N4 waveguides with microheater on top of it. The thermo-optic effect is utilized to lock one of the MRR resonances to an acetylene line. This locked MRR is then used to stabilize other laser sources at 980 nm and 1550 nm wavelength. By beating the stabilized laser to another stabilized laser, we obtained frequency instability floor of 4 ×10-9 at around 100 s in terms of Allan deviation. Such stable and accurate chip scale sources are expected to serve as important building block in diverse fields such as communication and metrology.

  8. Microlasers based on high-Q rare-earth-doped aluminum oxide resonators on silicon (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Bradley, Jonathan D. B.; Su, Zhan; Frankis, Henry C.; Magden, Emir Salih; Li, Nanxi; Byrd, Matthew; Purnawirman, Purnawirman; Shah Hosseini, Ehsan; Adam, Thomas N.; Leake, Gerald; Coolbaugh, Douglas; Watts, Michael R.

    2017-02-01

    One of the key challenges in the field of silicon photonics remains the development of compact integrated light sources. In one approach, rare-earth-doped glass microtoroid and microdisk lasers have been integrated on silicon and exhibit ultra-low thresholds. However, such resonator structures are isolated on the chip surface and require an external fiber to couple light to and from the cavity. Here, we review our recent work on monolithically integrated rare-earth-doped aluminum oxide microcavity lasers on silicon. The microlasers are enabled by a novel high-Q cavity design, which includes a co-integrated silicon nitride bus waveguide and a silicon dioxide trench filled with rare-earth-doped aluminum oxide. In passive (undoped) microresonators we measure internal quality factors as high as 3.8 × 105 at 0.98 µm and 5.7 × 105 at 1.5 µm. In ytterbium, erbium, and thulium-doped microcavities with diameters ranging from 80 to 200 µm we show lasing at 1.0, 1.5 and 1.9 µm, respectively. We observe sub-milliwatt lasing thresholds, approximately 10 times lower than previously demonstrated in monolithic rare-earth-doped lasers on silicon. The entire fabrication process, which includes post-processing deposition of the gain medium, is silicon-compatible and allows for integration with other silicon-based photonic devices. Applications of such rare earth microlasers in communications and sensing and recent design enhancements will be discussed.

  9. Low power consumption and continuously tunable all-optical microwave filter based on an opto-mechanical microring resonator.

    PubMed

    Liu, Li; Yang, Yue; Li, Zhihua; Jin, Xing; Mo, Wenqin; Liu, Xing

    2017-01-23

    We propose and experimentally demonstrate a continuously tunable all-optical microwave filter using a silicon opto-mechanical microring resonator (MRR). By finely adjusting the pump light with submilliwatt power level, transmission spectrum of the MRR could be continuously shifted based on the nonlinear effects, including the opto-mechanical effect and thermo-optic effect. Therefore, in the case of optical single sideband (OSSB) modulation, the frequency intervals between the optical carrier (near one MRR resonance) and the corresponding resonance could be flexibly manipulated, which is the critical factor to achieve continuously tunable microwave photonic filter (MPF). In the experiment, the central frequency of the MPF could be continuously tuned from 6 GHz to 19 GHz with the pump power lower than -2.5 dBm. The proposed opto-mechanical device is competent to process microwave signals with dominant advantages, such as compact footprint, all-optical control and low power consumption. In the future, using light to control light, the opto-mechanical structure on silicon platforms might have many other potential applications in microwave systems, such as microwave switch.

  10. Graphene-silicon microring resonator enhanced all-optical up and down wavelength conversion of QPSK signal.

    PubMed

    Hu, Xiao; Long, Yun; Ji, Mengxi; Wang, Andong; Zhu, Long; Ruan, Zhengsen; Wang, Yi; Wang, Jian

    2016-04-04

    We fabricate a nonlinear optical device based on graphene-silicon microring resonator (GSMR). Using such graphene-assisted nonlinear optical device, we experimentally demonstrate up and down wavelength conversion of a 10-Gbaud quadrature phase-shift keying (QPSK) signal by exploiting degenerate four-wave mixing (FWM) progress in the fabricated GSMR. We study the conversion efficiency as a function of the pump power. In addition, the resonant wavelength of GSMR is tuned by changing the temperature from 20°C to 40°C. We evaluate the bit-error rate (BER) performance for up and down wavelength conversion. The observed optical signal-to-noise ratio (OSNR) penalties for QPSK up and down wavelength conversion are less than 1.4 dB at a BER of 1 × 10-3. The BER performance as a function of the pump power for up wavelength conversion is also assessed. The minimum OSNR penalty is less than 0.8 dB when the pump power is 13.3 dBm.

  11. Quantitative, label-free detection of five protein biomarkers using multiplexed arrays of silicon photonic microring resonators.

    PubMed

    Washburn, Adam L; Luchansky, Matthew S; Bowman, Adrienne L; Bailey, Ryan C

    2010-01-01

    Because of the inherent complexity of biochemical pathways commonly altered in disease states, it has become accepted that multiplexed analyses can provide a more informative biomolecular understanding of disease onset and progression. Importantly, compared to conventional single-parameter assays, the detailed biomolecular insight gleaned from multiparameter measurements has the potential to greatly improve disease diagnostics, prognostics, and theragnostics. We have previously reported the utility of silicon photonic microring resonators for the sensitive quantitation of a single disease biomarker and herein demonstrate the first example of optical microcavity resonator arrays performing quantitative, label-free, multiplexed analyses of clinically relevant protein biomarkers. In this report, the concentrations of prostate specific antigen (PSA), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), tumor necrosis factor-alpha (TNF-alpha), and interleukin-8 (IL-8) are simultaneously determined in three unknown protein cocktail solutions. This letter demonstrates that multiple immunoassays can be performed concurrently on a microresonator platform without any accompanying loss of sensitivity or measurement precision, and therefore, this report lays the groundwork for future applications involving multiplexed analysis of clinically relevant samples.

  12. Generating photon pairs from a silicon microring resonator using an electronic step recovery diode for pump pulse generation

    NASA Astrophysics Data System (ADS)

    Savanier, Marc; Mookherjea, Shayan

    2016-06-01

    Generation of photon pairs from compact, manufacturable, and inexpensive silicon (Si) photonic devices at room temperature may help develop practical applications of quantum photonics. An important characteristic of photon-pair generation is the two-photon joint spectral intensity, which describes the frequency correlations of the photon pair. Recent attempts to generate a factorizable photon-pair state suitable for heralding have used short optical pump pulses from mode-locked lasers, which are much more expensive and bigger table-top or rack-sized instruments compared with the Si microchip used for generating photon pairs, and thus dominate the cost and inhibit the miniaturization of the source. Here, we generate photon pairs from an Si microring resonator by using an electronic step-recovery diode to drive an electro-optic modulator which carves the pump light from a continuous-wave laser diode into pulses of the appropriate width, thus potentially eliminating the need for optical mode-locked lasers.

  13. Generating photon pairs from a silicon microring resonator using an electronic step recovery diode for pump pulse generation

    SciTech Connect

    Savanier, Marc Mookherjea, Shayan

    2016-06-20

    Generation of photon pairs from compact, manufacturable, and inexpensive silicon (Si) photonic devices at room temperature may help develop practical applications of quantum photonics. An important characteristic of photon-pair generation is the two-photon joint spectral intensity, which describes the frequency correlations of the photon pair. Recent attempts to generate a factorizable photon-pair state suitable for heralding have used short optical pump pulses from mode-locked lasers, which are much more expensive and bigger table-top or rack-sized instruments compared with the Si microchip used for generating photon pairs, and thus dominate the cost and inhibit the miniaturization of the source. Here, we generate photon pairs from an Si microring resonator by using an electronic step-recovery diode to drive an electro-optic modulator which carves the pump light from a continuous-wave laser diode into pulses of the appropriate width, thus potentially eliminating the need for optical mode-locked lasers.

  14. Microring embedded hollow polymer fiber laser

    SciTech Connect

    Linslal, C. L. Sebastian, S.; Mathew, S.; Radhakrishnan, P.; Nampoori, V. P. N.; Girijavallabhan, C. P.; Kailasnath, M.

    2015-03-30

    Strongly modulated laser emission has been observed from rhodamine B doped microring resonator embedded in a hollow polymer optical fiber by transverse optical pumping. The microring resonator is fabricated on the inner wall of a hollow polymer fiber. Highly sharp lasing lines, strong mode selection, and a collimated laser beam are observed from the fiber. Nearly single mode lasing with a side mode suppression ratio of up to 11.8 dB is obtained from the strongly modulated lasing spectrum. The microring embedded hollow polymer fiber laser has shown efficient lasing characteristics even at a propagation length of 1.5 m.

  15. Phase-dependent interference between frequency doubled comb lines in a χ(2) phase-matched aluminum nitride microring.

    PubMed

    Jung, Hojoong; Guo, Xiang; Zhu, Na; Papp, Scott B; Diddams, Scott A; Tang, Hong X

    2016-08-15

    Nonlinear optical conversion with frequency combs is important for self-referencing and for generating shorter wavelength combs. Here we demonstrate efficient frequency comb doubling through the combination of second-harmonic generation (SHG) and sum-frequency generation (SFG) of an input comb with a high Q, phase-matched χ(2) microring resonator. Phase coherence of the SHG and SFG nonlinear conversion processes is confirmed by sinusoidal phase-dependent interference between frequency doubled comb lines.

  16. Multiplex detection of pathogen biomarkers in human blood, serum, and saliva using silicon photonic microring resonators

    NASA Astrophysics Data System (ADS)

    Estrada, I. A.; Burlingame, R. W.; Wang, A. P.; Chawla, K.; Grove, T.; Wang, J.; Southern, S. O.; Iqbal, M.; Gunn, L. C.; Gleeson, M. A.

    2015-05-01

    Genalyte has developed a multiplex silicon photonic chip diagnostics platform (MaverickTM) for rapid detection of up to 32 biological analytes from a drop of sample in just 10 to 20 minutes. The chips are manufactured with waveguides adjacent to ring resonators, and probed with a continuously variable wavelength laser. A shift in the resonant wavelength as mass binds above the ring resonators is measured and is directly proportional to the amount of bound macromolecules. We present here the ability to multiplex the detection of hemorrhagic fever antigens in whole blood, serum, and saliva in a 16 minute assay. Our proof of concept testing of a multiplex antigencapture chip has the ability to detect Zaire Ebola (ZEBOV) recombinant soluble glycoprotein (rsGP), Marburg virus (MARV) Angola recombinant glycoprotein (rGP) and dengue nonstructural protein I (NS1). In parallel, detection of 2 malaria antigens has proven successful, but has yet to be incorporated into multiplex with the others. Each assay performs with sensitivity ranging from 1.6 ng/ml to 39 ng/ml depending on the antigen detected, and with minimal cross-reactivity.

  17. High-Q Wafer Level Package Based on Modified Tri-Layer Anodic Bonding and High Performance Getter and Its Evaluation for Micro Resonant Pressure Sensor

    PubMed Central

    Wang, Liying; Du, Xiaohui; Wang, Lingyun; Xu, Zhanhao; Zhang, Chenying; Gu, Dandan

    2017-01-01

    In order to achieve and maintain a high quality factor (high-Q) for the micro resonant pressure sensor, this paper presents a new wafer level package by adopting cross-layer anodic bonding technique of the glass/silicon/silica (GSS) stackable structure and integrated Ti getter. A double-layer structure similar to a silicon-on-insulator (SOI) wafer is formed after the resonant layer and the pressure-sensitive layer are bonded by silicon direct bonding (SDB). In order to form good bonding quality between the pressure-sensitive layer and the glass cap layer, the cross-layer anodic bonding technique is proposed for vacuum package by sputtering Aluminum (Al) on the combination wafer of the pressure-sensitive layer and the resonant layer to achieve electrical interconnection. The model and the bonding effect of this technique are discussed. In addition, in order to enhance the performance of titanium (Ti) getter, the prepared and activation parameters of Ti getter under different sputtering conditions are optimized and discussed. Based on the optimized results, the Ti getter (thickness of 300 nm to 500 nm) is also deposited on the inside of the glass groove by magnetron sputtering to maintain stable quality factor (Q). The Q test of the built testing system shows that the number of resonators with a Q value of more than 10,000 accounts for more than 73% of the total. With an interval of 1.5 years, the Q value of the samples remains almost constant. It proves the proposed cross-layer anodic bonding and getter technique can realize high-Q resonant structure for long-term stable operation. PMID:28300752

  18. High-Q Wafer Level Package Based on Modified Tri-Layer Anodic Bonding and High Performance Getter and Its Evaluation for Micro Resonant Pressure Sensor.

    PubMed

    Wang, Liying; Du, Xiaohui; Wang, Lingyun; Xu, Zhanhao; Zhang, Chenying; Gu, Dandan

    2017-03-16

    In order to achieve and maintain a high quality factor (high-Q) for the micro resonant pressure sensor, this paper presents a new wafer level package by adopting cross-layer anodic bonding technique of the glass/silicon/silica (GSS) stackable structure and integrated Ti getter. A double-layer structure similar to a silicon-on-insulator (SOI) wafer is formed after the resonant layer and the pressure-sensitive layer are bonded by silicon direct bonding (SDB). In order to form good bonding quality between the pressure-sensitive layer and the glass cap layer, the cross-layer anodic bonding technique is proposed for vacuum package by sputtering Aluminum (Al) on the combination wafer of the pressure-sensitive layer and the resonant layer to achieve electrical interconnection. The model and the bonding effect of this technique are discussed. In addition, in order to enhance the performance of titanium (Ti) getter, the prepared and activation parameters of Ti getter under different sputtering conditions are optimized and discussed. Based on the optimized results, the Ti getter (thickness of 300 nm to 500 nm) is also deposited on the inside of the glass groove by magnetron sputtering to maintain stable quality factor (Q). The Q test of the built testing system shows that the number of resonators with a Q value of more than 10,000 accounts for more than 73% of the total. With an interval of 1.5 years, the Q value of the samples remains almost constant. It proves the proposed cross-layer anodic bonding and getter technique can realize high-Q resonant structure for long-term stable operation.

  19. On the applications of micror=-1 metamaterial lenses for magnetic resonance imaging.

    PubMed

    Freire, Manuel J; Jelinek, Lukas; Marques, Ricardo; Lapine, Mikhail

    2010-03-01

    In this work some possible applications of negative permeability magnetic metamaterial lenses for magnetic resonance imaging (MRI) are analyzed. It is shown that using magnetic metamaterials lenses it is possible to manipulate the spatial distribution of the radio-frequency (RF) field used in MR systems and, under some circumstances, improve the sensitivity of surface coils. Furthermore a collimation of the RF field, phenomenon that may find application in parallel imaging, is presented. MR images of real tissues are shown in order to prove the suitability of the theoretical analysis for practical applications.

  20. Nonlinear reversal of the PT -symmetric phase transition in a system of coupled semiconductor microring resonators

    NASA Astrophysics Data System (ADS)

    Hassan, Absar U.; Hodaei, Hossein; Miri, Mohammad-Ali; Khajavikhan, Mercedeh; Christodoulides, Demetrios N.

    2015-12-01

    A system of two coupled semiconductor-based resonators is studied when lasing around an exceptional point. We show that the presence of nonlinear saturation effects can have important ramifications on the transition behavior of this system. In sharp contrast with linear PT -symmetric configurations, nonlinear processes are capable of reversing the order in which the symmetry breaking occurs. Yet, even in the nonlinear regime, the resulting non-Hermitian states still retain the structural form of the corresponding linear eigenvectors expected above and below the phase-transition point. The conclusions of our analysis are in agreement with experimental data.

  1. Test of the FDTD accuracy in the analysis of the scattering resonances associated with high-Q whispering-gallery modes of a circular cylinder.

    PubMed

    Boriskin, Artem V; Boriskina, Svetlana V; Rolland, Anthony; Sauleau, Ronan; Nosich, Alexander I

    2008-05-01

    Our objective is the assessment of the accuracy of a conventional finite-difference time-domain (FDTD) code in the computation of the near- and far-field scattering characteristics of a circular dielectric cylinder. We excite the cylinder with an electric or magnetic line current and demonstrate the failure of the two-dimensional FDTD algorithm to accurately characterize the emission rate and the field patterns near high-Q whispering-gallery-mode resonances. This is proven by comparison with the exact series solutions. The computational errors in the emission rate are then studied at the resonances still detectable with FDTD, i.e., having Q-factors up to 10(3).

  2. Pulsed-laser excitation of acoustic modes in open high-Q photoacoustic resonators for trace gas monitoring: results for C2H4

    NASA Astrophysics Data System (ADS)

    Brand, Christian; Winkler, Andreas; Hess, Peter; Miklós, András; Bozóki, Zoltán; Sneider, János

    1995-06-01

    The pulsed excitation of acoustic resonances was studied with a continuously monitoring photoacoustic detector system. Acoustic waves were generated in C2H4/N 2 gas mixtures by light absorption of the pulses from a transversely excited atmospheric CO2 laser. The photoacoustic part consisted of high-Q cylindrical resonators (Q factor 820 for the first radial mode in N2) and two adjoining variable acoustic filter systems. The time-resolved signal was Fourier transformed to a frequency spectrum of high resolution. For the first radial mode a Lorentzian profile was fitted to the measured data. The outside noise suppression and the signal-to-noise ratio were investigated in a normal laboratory environment in the flow-through mode. The acoustic and electric filter system combined with the

  3. Ultra-high frequency, high Q/volume micromechanical resonators in a planar AlN phononic crystal

    NASA Astrophysics Data System (ADS)

    Ghasemi Baboly, M.; Alaie, S.; Reinke, C. M.; El-Kady, I.; Leseman, Z. C.

    2016-07-01

    This paper presents the first design and experimental demonstration of an ultrahigh frequency complete phononic crystal (PnC) bandgap aluminum nitride (AlN)/air structure operating in the GHz range. A complete phononic bandgap of this design is used to efficiently and simultaneously confine elastic vibrations in a resonator. The PnC structure is fabricated by etching a square array of air holes in an AlN slab. The fabricated PnC resonator resonates at 1.117 GHz, which corresponds to an out-of-plane mode. The measured bandgap and resonance frequencies are in very good agreement with the eigen-frequency and frequency-domain finite element analyses. As a result, a quality factor/volume of 7.6 × 1017/m3 for the confined resonance mode was obtained that is the largest value reported for this type of PnC resonator to date. These results are an important step forward in achieving possible applications of PnCs for RF communication and signal processing with smaller dimensions.

  4. Electro-optic modulation of high-Q lithium niobate whispering gallery resonator with integrated ground plane (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Douglas, Kenneth; Moore, Jeremy; Friedman, Thomas; Eichenfield, Matthew

    2017-02-01

    We experimentally demonstrate electro-optic modulation in thin film lithium niobate microdisk resonators with an integrated bottom electrode fabricated from a z-cut Lithium Niobate on Insulator wafer. The structure consisted of a 400nm thick crystalline z-cut lithium niobate/2um SiO2/20nm Cr/100nm Au/10nm Cr film stack on top of a z-cut lithium niobate handle wafer. The integrated bottom electrode is located 2um beneath the resonator. This proximity, coupled with positioning an electrical probe close to the top of the resonator, allows large optical frequency shifts with low voltages. We observed a 0.111pm/V resonance shift of vertically polarized (TM) optical whispering gallery modes, with the voltage applied perpendicular to the wafer surface. This corresponds to a shift of one optical linewidth at an applied voltage of 180V, using the r33 component of the eletro-optic tensor. We observed a smaller shift of 0.066pm/V for the radially polarized (TE) modes, using the r13 component of the electro-optic tensor. The experiment was performed using a 1550nm tunable laser that was coupled to the optical resonator modes using a tapered optical fiber. To measure the electro-optic shift of the resonance, a voltage was applied across the device via DC probe tips and the peak shift was calibrated with a Toptica WS6 IR wavemeter with 200 MHz absolute accuracy. We also present a finite element model that accurately predicts the resonance shift as a function of applied voltage for both polarizations.

  5. Evaluation and optimization of quartz resonant-frequency retuned fork force sensors with high Q factors, and the associated electric circuits, for non-contact atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Ooe, Hiroaki; Fujii, Mikihiro; Tomitori, Masahiko; Arai, Toyoko

    2016-02-01

    High-Q factor retuned fork (RTF) force sensors made from quartz tuning forks, and the electric circuits for the sensors, were evaluated and optimized to improve the performance of non-contact atomic force microscopy (nc-AFM) performed under ultrahigh vacuum (UHV) conditions. To exploit the high Q factor of the RTF sensor, the oscillation of the RTF sensor was excited at its resonant frequency, using a stray capacitance compensation circuit to cancel the excitation signal leaked through the stray capacitor of the sensor. To improve the signal-to-noise (S/N) ratio in the detected signal, a small capacitor was inserted before the input of an operational (OP) amplifier placed in an UHV chamber, which reduced the output noise from the amplifier. A low-noise, wideband OP amplifier produced a superior S/N ratio, compared with a precision OP amplifier. The thermal vibrational density spectra of the RTF sensors were evaluated using the circuit. The RTF sensor with an effective spring constant value as low as 1000 N/m provided a lower minimum detection limit for force differentiation. A nc-AFM image of a Si(111)-7 × 7 surface was produced with atomic resolution using the RTF sensor in a constant frequency shift mode; tunneling current and energy dissipation images with atomic resolution were also simultaneously produced. The high-Q factor RTF sensor showed potential for the high sensitivity of energy dissipation as small as 1 meV/cycle and the high-resolution analysis of non-conservative force interactions.

  6. Evaluation and optimization of quartz resonant-frequency retuned fork force sensors with high Q factors, and the associated electric circuits, for non-contact atomic force microscopy.

    PubMed

    Ooe, Hiroaki; Fujii, Mikihiro; Tomitori, Masahiko; Arai, Toyoko

    2016-02-01

    High-Q factor retuned fork (RTF) force sensors made from quartz tuning forks, and the electric circuits for the sensors, were evaluated and optimized to improve the performance of non-contact atomic force microscopy (nc-AFM) performed under ultrahigh vacuum (UHV) conditions. To exploit the high Q factor of the RTF sensor, the oscillation of the RTF sensor was excited at its resonant frequency, using a stray capacitance compensation circuit to cancel the excitation signal leaked through the stray capacitor of the sensor. To improve the signal-to-noise (S/N) ratio in the detected signal, a small capacitor was inserted before the input of an operational (OP) amplifier placed in an UHV chamber, which reduced the output noise from the amplifier. A low-noise, wideband OP amplifier produced a superior S/N ratio, compared with a precision OP amplifier. The thermal vibrational density spectra of the RTF sensors were evaluated using the circuit. The RTF sensor with an effective spring constant value as low as 1000 N/m provided a lower minimum detection limit for force differentiation. A nc-AFM image of a Si(111)-7 × 7 surface was produced with atomic resolution using the RTF sensor in a constant frequency shift mode; tunneling current and energy dissipation images with atomic resolution were also simultaneously produced. The high-Q factor RTF sensor showed potential for the high sensitivity of energy dissipation as small as 1 meV/cycle and the high-resolution analysis of non-conservative force interactions.

  7. Improved transmission performance resulting from the reduced chirp of a semiconductor laser coupled to an external high-Q resonator

    SciTech Connect

    Cartledge, J.C. )

    1990-05-01

    The coupling of a Fabry--Perot laser to an external high-{ital Q} resonator, whose resonance frequencies are not altered by changes in the carrier density, yields a dynamic single-longitudinal-mode laser with a significantly reduced transient frequency chirp. The improvement in the receiver sensitivity due to the reduced chirp is examined for NRZ and RZ intensity modulation, direct detection systems operating in the 1.55-{mu}m wavelength region with conventional single-mode optical fiber. The methodology involves a solving modified rate equations numerically for the optical power and phase of the external resonator laser in response to an injected current waveform, modeling the signal transmission properties of single-mode optical fibers by convolution and modulus squared operations, and using a truncated pulse train approximation to evaluate the probability of error in the presence of intersymbol interference, shot noise, APD multiplication noise, and preamplifier circuit noise.

  8. Hybrid III-V on Si grating as a broadband reflector and a high-Q resonator

    NASA Astrophysics Data System (ADS)

    Chung, Il-Sug; Taghizadeh, Alireza; Park, Gyeong Cheol

    2016-03-01

    Hybrid grating (HG) with a high-refractive-index cap layer added onto a high contrast grating (HCG), can provide a high reflectance close 100 % over a broader wavelength range than HCGs, or work as a ultrahigh quality (Q) factor resonator. The reflection and resonance properties of HGs have been investigated and the mechanisms leading to these properties are discussed. A HG reflector sample integrating a III-V cap layer with InGaAlAs quantum wells onto a Si grating has been fabricated and its reflection property has been characterized. The HG-based lasers have a promising prospect for silicon photonics light source or high-speed laser applications.

  9. Optical Resonators and Filters

    NASA Astrophysics Data System (ADS)

    Haus, Hermann A.; Popović, Miloš A.; Watts, Michael R.; Manolatou, Christina; Little, Brent E.; Chu, Sai T.

    Dielectric optical resonators of small size are considered for densely-integrated optical components. High-index-contrast microresonators of low Q are shown, using microwave design principles, to permit wavelength-sized, low-loss, reflectionless waveguide bends and low-crosstalk waveguide crossings. The analysis and synthesis of high Q high-order microring- and racetrack-resonator channel add/drop filters are reviewed, supplemented by simulation examples. Standing-wave, distributed Bragg resonator filters are also described. The study is unified by a coupled-mode theory approach. Rigorous numerical simulations are justified for the design of high-index-contrast optical "circuits". Integrated-optical components are described within a polarization-diversity scheme that circumvents the inherent polarization dependence of high-index-contrast devices. Filters fabricated in academic and commercial research, and a review of microring resonator technology, advances and applications are presented.

  10. Simulation of coupled bunch mode growth driven by a high-Q resonator: A transient response approach

    SciTech Connect

    Stahl, S.; Bogacz, S.A.

    1989-03-01

    In this article the use of a longitudinal phase-space tracking code, ESME, to simulate the growth of a coupled-bunch instability in the Fermilab Booster is examined. A description of the calculation of the resonant response is given, and results are presented for the growth of the coupled bunch instability in a ring in which all of the rf buckets are equally populated and in one in which several consecutive buckets are empty. 4 refs., 6 figs.

  11. Azimuthal-order variations of surface-roughness-induced mode splitting and scattering loss in high-Q microdisk resonators.

    PubMed

    Li, Qing; Eftekhar, Ali A; Xia, Zhixuan; Adibi, Ali

    2012-05-01

    We report an experimental observation of strong variations of quality factor and mode splitting among whispering-gallery modes with the same radial order and different azimuthal orders in a scattering-limited microdisk resonator. A theoretical analysis based on the statistical properties of the surface roughness reveals that mode splittings for different azimuthal orders are uncorrelated, and variations of mode splitting and quality factor among the same radial mode family are possible. Simulation results agree well with the experimental observations.

  12. A wavelength tunable ONU transmitter based on multi-mode Fabry-Perot laser and micro-ring resonator for bandwidth symmetric TWDM-PON

    NASA Astrophysics Data System (ADS)

    Gao, Zhensen; Sun, Xiao; Zhang, Kaibin

    2016-02-01

    Wavelength tunable optical transmitter is an essential component for the newly standardized time and wavelength division multiplexed passive optical network (TWDM-PON), where tunable ONU with 10Gb/s bit rate is desired to provide 40Gb/s symmetric bandwidth. In this paper, a novel wavelength tunable optical transmitter is proposed by reusing legacy low speed multi-mode Fabry-Perot laser and connecting it with an integrated photonic chip with two coupled micro-ring resonators to generate a tunable single mode signal based on Vernier effect for 10Gb/s high speed modulation, which makes it as a promising solution for colorless ONU in future symmetric TWDM-PON.

  13. Design and optical characterization of high-Q guided-resonance modes in the slot-graphite photonic crystal lattice.

    PubMed

    Martínez, Luis Javier; Huang, Ningfeng; Ma, Jing; Lin, Chenxi; Jaquay, Eric; Povinelli, Michelle L

    2013-12-16

    A new photonic crystal structure is generated by using a regular graphite lattice as the base and adding a slot in the center of each unit cell to enhance field confinement. The theoretical Q factor in an ideal structure is over 4 × 10(5). The structure was fabricated on a silicon-on-insulator wafer and optically characterized by transmission spectroscopy. The resonance wavelength and quality factor were measured as a function of slot height. The measured trends show good agreement with simulation.

  14. Minimalist-design, high-functionality, micro-ring resonator-based optical filter with narrow linewidth and low group delay using Looped Back Over- and Under-coupled Resonator (LOBOUR)

    NASA Astrophysics Data System (ADS)

    Ye, Bo; Dingel, Benjamin B.; Cui, Weili

    2013-01-01

    We present a minimalist design but high functionality micro-ring resonator based optical filter with narrow linewidth and low group delay using a novel design we called LOBOUR for LOoped-Back Over- and Under- Coupled Resonator (LOBOUR). The characteristics of both narrow linewidth and low group delay (low chromatic dispersion) generally do not come together especially when using a single ring resonator. The Cascaded Over- and Under-Coupled Resonator (COUR) design was able to achieve this goal but introduced many practical fabrication issues. Here, we present an alternative design to COUR which uses only one ring resonator and without fabrication and manufacturing issues. It can achieve 50 dB extinction ratio and tens of ps performance. We also present important parameter selection mapping for LOBOUR.

  15. Inline microring reflector for photonic applications

    NASA Astrophysics Data System (ADS)

    Kang, Young Mo

    The microring is a compact resonator that is used as a versatile building block in photonic circuits ranging from filters, modulators, logic gates, sensors, switches, multiplexers, and laser cavities. The Bragg grating is a periodic structure that allows the selection of a narrow bandwidth of spectrum for stable lasing operation. In this dissertation, we study analysis and simulations of a compact microring based reflector assembled by forming a Bragg grating into a loop. With the appropriate design, the microring resonance can precisely align with the reflection peak of the grating while all other peaks are suppressed by reflection nulls of the grating. The field buildup at the resonance effectively amplifies small reflection of the grating, thereby producing significant overall reflection from the ring, and it is possible to achieve a stable narrow linewidth compact laser by forming a single mode laser cavity. The device operation principle is studied from two distinct perspectives; the first looks at coupling of two contra-directional traveling waves within the ring whereas the second aspect investigates relative excitation of the two competing microring resonant modes. In the former method, we relate the steady state amplitudes of the two traveling waves to the reflection spectrum of the grating and solve for the reflection and transmission response for each wavelength of interest. In the latter approach, we expand the field in terms of the resonant modes of the ring cavity and derive transfer functions for reflection and transmission from the nearby mode frequencies. The angular periodicity of the reflective microring geometry allows us to effectively simulate the resonant modes from a computational domain of a single period grating when the continuity boundary condition is applied. We successfully predict the reflection and transmission response of a Si3N 4/SiO2 microring reflector using this method---otherwise too large to carry out full-wave simulation

  16. Single-crystal sapphire resonator at millikelvin temperatures: Observation of thermal bistability in high- Q factor whispering gallery modes

    NASA Astrophysics Data System (ADS)

    Creedon, Daniel L.; Tobar, Michael E.; Le Floch, Jean-Michel; Reshitnyk, Yarema; Duty, Timothy

    2010-09-01

    Resonance modes in single crystal sapphire (α-Al2O3) exhibit extremely high electrical and mechanical Q factors ( ≈109 at 4 K), which are important characteristics for electromechanical experiments at the quantum limit. We report the cool down of a bulk sapphire sample below superfluid liquid-helium temperature (1.6 K) to as low as 25 mK. The electromagnetic properties were characterized at microwave frequencies, and we report the observation of electromagnetically induced thermal bistability in whispering gallery modes due to the material T3 dependence on thermal conductivity and the ultralow dielectric loss tangent. We identify “magic temperatures” between 80 and 2100 mK, the lowest ever measured, at which the onset of bistability is suppressed and the frequency-temperature dependence is annulled. These phenomena at low temperatures make sapphire suitable for quantum metrology and ultrastable clock applications, including the possible realization of the quantum-limited sapphire clock.

  17. Low-power all-optical microwave filter with tunable central frequency and bandwidth based on cascaded opto-mechanical microring resonators.

    PubMed

    Liu, Li; Chen, Zhi; Jin, Xing; Yang, Yue; Yu, Zhihua; Zhang, Jingjing; Zhang, Lijun; Wang, Hong

    2017-07-24

    We propose and experimentally demonstrate an all-optical microwave filter with tunable central frequency and bandwidth based on two cascaded silicon opto-mechanical microring resonators (MRRs). Due to the Vernier effect, transmission spectrum of the cascaded MRRs is a series of notch bimodal distribution. In the case of intensity modulation with optical double-sideband (ODSB) signals, the optical carrier is fixed between the two resonant peaks of one notch bimodal distribution. By injecting two pump powers to control the above two resonance red-shifts based on the nonlinear effects in opto-mechanical MRRs, the frequency intervals between the optical carrier and the two resonances could be flexibly manipulated for tunable microwave processing. In the experiment, with the highest required pump powers of 1.65 mW and 0.96 mW, the central frequency and bandwidth of the notch microwave photonic filter (MPF) could be tuned from 5 GHz to 36 GHz and 6.7 GHz to 10.3 GHz, respectively. The proposed opto-mechanical device is competent to process microwave signals with dominant advantages of all-optical control, compact footprint, wide tuning range and low-power consumption, which has significant applications in on-chip microwave systems.

  18. A high-Q resonant pressure microsensor with through-glass electrical interconnections based on wafer-level MEMS vacuum packaging.

    PubMed

    Luo, Zhenyu; Chen, Deyong; Wang, Junbo; Li, Yinan; Chen, Jian

    2014-12-16

    This paper presents a high-Q resonant pressure microsensor with through-glass electrical interconnections based on wafer-level MEMS vacuum packaging. An approach to maintaining high-vacuum conditions by integrating the MEMS fabrication process with getter material preparation is presented in this paper. In this device, the pressure under measurement causes a deflection of a pressure-sensitive silicon square diaphragm, which is further translated to stress build up in "H" type doubly-clamped micro resonant beams, leading to a resonance frequency shift. The device geometries were optimized using FEM simulation and a 4-inch SOI wafer was used for device fabrication, which required only three photolithographic steps. In the device fabrication, a non-evaporable metal thin film as the getter material was sputtered on a Pyrex 7740 glass wafer, which was then anodically bonded to the patterned SOI wafer for vacuum packaging. Through-glass via holes predefined in the glass wafer functioned as the electrical interconnections between the patterned SOI wafer and the surrounding electrical components. Experimental results recorded that the Q-factor of the resonant beam was beyond 22,000, with a differential sensitivity of 89.86 Hz/kPa, a device resolution of 10 Pa and a nonlinearity of 0.02% F.S with the pressure varying from 50 kPa to 100 kPa. In addition, the temperature drift coefficient was less than -0.01% F.S/°C in the range of -40 °C to 70 °C, the long-term stability error was quantified as 0.01% F.S over a 5-month period and the accuracy of the microsensor was better than 0.01% F.S.

  19. A High-Q Resonant Pressure Microsensor with Through-Glass Electrical Interconnections Based on Wafer-Level MEMS Vacuum Packaging

    PubMed Central

    Luo, Zhenyu; Chen, Deyong; Wang, Junbo; Li, Yinan; Chen, Jian

    2014-01-01

    This paper presents a high-Q resonant pressure microsensor with through-glass electrical interconnections based on wafer-level MEMS vacuum packaging. An approach to maintaining high-vacuum conditions by integrating the MEMS fabrication process with getter material preparation is presented in this paper. In this device, the pressure under measurement causes a deflection of a pressure-sensitive silicon square diaphragm, which is further translated to stress build up in “H” type doubly-clamped micro resonant beams, leading to a resonance frequency shift. The device geometries were optimized using FEM simulation and a 4-inch SOI wafer was used for device fabrication, which required only three photolithographic steps. In the device fabrication, a non-evaporable metal thin film as the getter material was sputtered on a Pyrex 7740 glass wafer, which was then anodically bonded to the patterned SOI wafer for vacuum packaging. Through-glass via holes predefined in the glass wafer functioned as the electrical interconnections between the patterned SOI wafer and the surrounding electrical components. Experimental results recorded that the Q-factor of the resonant beam was beyond 22,000, with a differential sensitivity of 89.86 Hz/kPa, a device resolution of 10 Pa and a nonlinearity of 0.02% F.S with the pressure varying from 50 kPa to 100 kPa. In addition, the temperature drift coefficient was less than −0.01% F.S/°C in the range of −40 °C to 70 °C, the long-term stability error was quantified as 0.01% F.S over a 5-month period and the accuracy of the microsensor was better than 0.01% F.S. PMID:25521385

  20. Broadband biphoton generation and statistics of quantum light in the UV-visible range in an AlGaN microring resonator.

    PubMed

    De Leonardis, Francesco; Soref, Richard A; Soltani, Mohammad; Passaro, Vittorio M N

    2017-09-12

    We present a physical investigation on the generation of correlated photon pairs that are broadly spaced in the ultraviolet (UV) and visible spectrum on a AlGaN/AlN integrated photonic platform which is optically transparent at these wavelengths. Using spontaneous four wave mixing (SFWM) in an AlGaN microring resonator, we show design techniques to satisfy the phase matching condition between the optical pump, the signal, and idler photon pairs, a condition which is essential and is a key hurdle when operating at short wavelength due to the strong normal dispersion of the material. Such UV-visible photon pairs are quite beneficial for interaction with qubit ions that are mostly in this wavelength range, and will enable heralding the photon-ion interaction. As a target application example, we present the systematic AlGaN microresonator design for generating signal and idler photon pairs using a blue wavelength pump, while the signal appears at the transition of ytterbium ion ((171)Yb(+), 369.5 nm) and the idler appears in the far blue or green range. The photon pairs have minimal crosstalk to the pump power due to their broad spacing in spectral wavelength, thereby relaxing the design of on-chip integrated filters for separating pump, signal and idler.

  1. Optical bistability in photonic crystal microrings with nonlinear dielectric materials.

    PubMed

    Ogusu, Kazuhiko; Takayama, Kosuke

    2008-05-12

    We study the linear resonance properties of several types of microrings in a two-dimensional photonic crystal (PC) consisting of a square lattice with air holes in dielectric using the plane-wave expansion method and the FDTD method. Moreover we investigate the nonlinear responses, especially optical bistability when an intense optical pulse is incident into the microrings. In this paper, Ag-As-Se chalcogenide glass is assumed as nonlinear dielectric, which has a high third-order nonlinearity. Although line-defect waveguides in an air-hole-type PC are usually multimoded, we can obtain interesting unique properties such as counter rotation of intracavity fields, transmission to all output ports, and unstable nonlinear oscillations in the multimoded PC microring. We can improve the resonance characteristics by partly introducing single-mode waveguides into microrings and can obtain stable optical bistability.

  2. Coupling Ideality of Integrated Planar High-Q Microresonators

    NASA Astrophysics Data System (ADS)

    Pfeiffer, Martin H. P.; Liu, Junqiu; Geiselmann, Michael; Kippenberg, Tobias J.

    2017-02-01

    Chip-scale optical microresonators with integrated planar optical waveguides are useful building blocks for linear, nonlinear, and quantum-optical photonic devices alike. Loss reduction through improving fabrication processes results in several integrated microresonator platforms attaining quality (Q ) factors of several millions. Beyond the improvement of the quality factor, the ability to operate the microresonator with high coupling ideality in the overcoupled regime is of central importance. In this regime, the dominant source of loss constitutes the coupling to a single desired output channel, which is particularly important not only for quantum-optical applications such as the generation of squeezed light and correlated photon pairs but also for linear and nonlinear photonics. However, to date, the coupling ideality in integrated photonic microresonators is not well understood, in particular, design-dependent losses and their impact on the regime of high ideality. Here we investigate design-dependent parasitic losses described by the coupling ideality of the commonly employed microresonator design consisting of a microring-resonator waveguide side coupled to a straight bus waveguide, a system which is not properly described by the conventional input-output theory of open systems due to the presence of higher-order modes. By systematic characterization of multimode high-Q silicon nitride microresonator devices, we show that this design can suffer from low coupling ideality. By performing 3D simulations, we identify the coupling to higher-order bus waveguide modes as the dominant origin of parasitic losses which lead to the low coupling ideality. Using suitably designed bus waveguides, parasitic losses are mitigated with a nearly unity ideality and strong overcoupling (i.e., a ratio of external coupling to internal resonator loss rate >9 ) are demonstrated. Moreover, we find that different resonator modes can exchange power through the coupler, which, therefore

  3. Subpicometer thermal shifts in silicon photonic micro-ring resonators with sol-gel claddings (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Namnabat, Soha; Kim, Kyung-Jo; Jones, Adam M.; Himmelhuber, Roland; DeRose, Christopher T.; Pomerene, Andrew; Lentine, Tony L.; Norwood, Robert A.

    2017-02-01

    Electronic interconnects are reaching their limit in terms of speed, dimensions and permissible power consumption. This has been a major concern in data centers and large scale computing platforms, creating limits to their scalability especially with respect to power consumption. Silicon photonic-electronic integration is viewed as a viable alternative that enables reliability, high efficiency, low cost and small footprint. In particular, silicon with its high refractive index, has enabled the integration a many individual optical elements (ring resonators) in small areas. Though silicon has a high thermo-optic coefficient (1.8×10^-4/°C) compared to silica, small thermal fluctuations can affect the optical performance especially for WDM applications. Therefore, a passive athermal solution for silicon photonic devices is required in order to reduce thermal sensitivity and power consumption. We have achieved this goal by replacing the silica top cladding with negative thermo-optic coefficient (TOC) materials. While polymers and titanium dioxide(titania) have a negative TOC, polymers can't handle high temperature processing and titania needs very tight thickness control and expensive deposition under vacuum. In this work we propose to use a sol-gel inorganic-organic hybrid material that has the benefits of both worlds. We were able to find optimum curing conditions to athermalize ring resonators by studying various sol-gel curing times and curing temperatures. Our athermal rings operate in a wide temperature range from 5C - 100C with thermal shifts below 1pm/C and low loss. Furthermore, we demonstrate that our athermal approach does not deleteriously effect critical device parameters, such as insertion loss and resonator Q factors.

  4. Analytical approach for modeling and performance analysis of microring resonators as optical filters with multiple output bus waveguides

    NASA Astrophysics Data System (ADS)

    Lakra, Suchita; Mandal, Sanjoy

    2017-06-01

    A quadruple micro-optical ring resonator (QMORR) with multiple output bus waveguides is mathematically modeled and analyzed by making use of the delay-line signal processing approach in Z-domain and Mason's gain formula. The performances of QMORR with two output bus waveguides with vertical coupling are analyzed. This proposed structure is capable of providing wider free spectral response from both the output buses with appreciable cross talk. Thus, this configuration could provide increased capacity to insert a large number of communication channels. The simulated frequency response characteristic and its dispersion and group delay characteristics are graphically presented using the MATLAB environment.

  5. Dynamically tuned high-Q AC-dipole implementation

    SciTech Connect

    Oddo, P.; Bai, M.; Dawson, W.C.; Meng, W.; Mernick, K.; Pai, C.; Roser, T.; Russo, T.

    2010-05-02

    AC-dipole magnets are typically implemented as a parallel LC resonant circuit. To maximize efficiency, it's beneficial to operate at a high Q. This, however, limits the magnet to a narrow frequency range. Current designs therefore operate at a low Q to provide a wider bandwidth at the cost of efficiency. Dynamically tuning a high Q resonant circuit tries to maintain a high efficiency while providing a wide frequency range. The results of ongoing efforts at BNL to implement dynamically tuned high-Q AC dipoles will be presented.

  6. A tunable notch filter using microelectromechanical microring with gap-variable busline coupler.

    PubMed

    Ikeda, Taro; Hane, Kazuhiro

    2013-09-23

    A microelectromechanical tunable notch filter using silicon-photonic freestanding waveguides is proposed, and the basic characteristics are experimentally investigated. The proposed filter is composed of a wavelength-tunable silicon microring resonator and a busline switch. The tunable microring consists of freestanding single-mode waveguides and air-gap directional waveguide couplers. The optical path length of the microring is varied physically by a displacement of electrostatic comb-drive actuator. The busline switch consists of a gap-variable waveguide coupling mechanism, which enables coupling the tunable microring with the busline by another electrostatic comb-drive actuator. During the wavelength tuning of microring, the busline can be disconnected from the microring. Therefore, the proposed device operates as a hitless wavelength-selective switch if they are connected in series. The waveguides are 320 nm in width and 340 nm in thickness. The resonant wavelength shift of the microring is 9.96 nm at the voltage of 26 V with the actuator displacement of 1.0 μm. The coupling to busline is adjusted from the switch-off state at the gap of 600 nm to the switch-on state corresponding to the critical coupling condition at the gap of 383 nm. The whole size of the wavelength-tunable filter with hitless mechanism is about 150 μm by 80 μm. Due to the capacitive operation of the comb-drive actuators, the power consumption is negligibly small.

  7. Measurement of differential cross sections via p(e,e^'&+circ;)n for studying high-lying resonances at high Q^2

    NASA Astrophysics Data System (ADS)

    Park, Kijun; Burkert, Volker

    2012-10-01

    An extensive experimental programs has been carried out at Jefferson Laboratory to study the excitation resonances using the CEBAF Large Acceptance Spectrometer (CLAS). Pion electroproduction on protons is sensitive to the resonance excitation and allows us to explore its internal structure. The CLAS is well suited for the study of a broad range of kinematics in the invariant mass W and photon virtuality Q^2 with nearly complete angular coverage for the hadronic decays. Electron scattering allows us to probe the effective degrees of freedom in excited nucleon states from meson-baryon cloud to dressed quarks in terms of varying distance scale. In this talk, we report the differential cross-sections for exclusive single charged pion electroproduction from proton targets. The kinematic range covers Q^2 from 1.7;GeV^2 to 4.5;GeV^2 and W from 1.6;GeV to 2.0;GeV. Separated structure functions are also presented and compared with the present calculations and previous measurements. This work, along with an upcoming analysis of same kinematics from exclusive p0̂ and p&+circ;&-circ; electroproduction will allow the determination of electro-couplings of several high-lying excited proton states, for the first time, at photon virtualities that correspond to transition toward dominance of quark degrees of freedom.

  8. Measurement of cross sections of p(e,e'π+)n for near pion threshold and high-lying resonances at high Q2

    NASA Astrophysics Data System (ADS)

    Park, Kijun

    2012-04-01

    During the last decade, remarkable experimental data have been collacted in an extensive programs to study the excitation of nucleon resonance (N*) at Jefferson Laboratory through pionelectroproduction using polarized electron beam and unpolarized proton target. The CEBAF Large Acceptance Spectrometer (CLAS) is well suited for the study of a broad range of kinematics in the invariant mass W and photon virtuality Q2 with nearly complete angular coverage for the hadronic decays. Electron scattering allows us to probe the effective degrees of freedom in excited nucleon states from meson-baryon to dressed quarks in terms of varying the distance scale. The study of nucleon structure allows us to understand these effective degrees of freedom. In this proceeding, I present preliminary cross sections for single pion production in mass range of high-lying resonances as well as near the pion threshold. Analysis of Nπ+ cross sections together with Nπ0 and Nππ exclusive electroproduction data, will allow us for the first time to determine electrocouplings of several high-lying excited proton states (W ≥ 1.6 GeV) at photon virtualities that correspond to the transition toward the dominance of quark degrees of freedom. I also present preliminary result on the E0+ multipole near pion threshold at 2.0 GeV2 ≤ Q2 ≤ 4.5 GeV2 using exclusive Nπ+ electroproduction data.

  9. Self-referenced silicon nitride array microring biosensor for toxin detection using glycans at visible wavelength

    NASA Astrophysics Data System (ADS)

    Ghasemi, Farshid; Eftekhar, Ali A.; Gottfried, David S.; Song, Xuezheng; Cummings, Richard D.; Adibi, Ali

    2013-02-01

    We report on application of on-chip referencing to improve the limit-of-detection (LOD) in compact silicon nitride (SiN) microring arrays. Microring resonators, fabricated by e-beam lithography and fluorine-based etching, are designed for visible wavelengths (656nm) and have a footprint of 20 x 20 μm. GM1 ganglioside is used as the specific ligand for recognition of Cholera Toxin Subunit B (CTB), with Ricinus Communis Agglutinin I (RCA I) as a negative control. Using micro-cantilever based printing less than 10 pL of glycan solution is consumed per microring. Real-time data on analyte binding is extracted from the shifts in resonance wavelengths of the microrings.

  10. Magnetically controllable silicon microring with ferrofluid cladding.

    PubMed

    El Amili, A; Souza, M C M M; Vallini, F; Frateschi, N C; Fainman, Y

    2016-12-01

    We experimentally investigate the application of magnetic fluids (MFs) on integrated silicon photonics. Using a ferrofluid-clad silicon microring resonator, we demonstrate active control of resonances by applying an external magnetic field. Relatively high loaded quality factors on the order of 6000 are achieved, despite the optical losses introduced by the magnetic nanoparticles. We demonstrate resonance shifts of 185 pm in response to a 110 Oe strong magnetic field, corresponding to an overall refractive index change of -3.2×10-3 for the cladding MF. The combination of MFs and integrated photonics could potentially lead to the development of magnetically controllable optical devices and ultra-compact cost-effective magnetic field sensors.

  11. Coherently Opening a High-Q Cavity

    NASA Astrophysics Data System (ADS)

    Tufarelli, Tommaso; Ferraro, Alessandro; Serafini, Alessio; Bose, Sougato; Kim, M. S.

    2014-04-01

    We propose a general framework to effectively "open" a high-Q resonator, that is, to release the quantum state initially prepared in it in the form of a traveling electromagnetic wave. This is achieved by employing a mediating mode that scatters coherently the radiation from the resonator into a one-dimensional continuum of modes such as a waveguide. The same mechanism may be used to "feed" a desired quantum field to an initially empty cavity. Switching between an open and "closed" resonator may then be obtained by controlling either the detuning of the scatterer or the amount of time it spends in the resonator. First, we introduce the model in its general form, identifying (i) the traveling mode that optimally retains the full quantum information of the resonator field and (ii) a suitable figure of merit that we study analytically in terms of the system parameters. Then, we discuss two feasible implementations based on ensembles of two-level atoms interacting with cavity fields. In addition, we discuss how to integrate traditional cavity QED in our proposal using three-level atoms.

  12. An integrated parity-time symmetric wavelength-tunable single-mode microring laser.

    PubMed

    Liu, Weilin; Li, Ming; Guzzon, Robert S; Norberg, Erik J; Parker, John S; Lu, Mingzhi; Coldren, Larry A; Yao, Jianping

    2017-05-12

    Mode control in a laser cavity is critical for a stable single-mode operation of a ring laser. In this study we propose and experimentally demonstrate an electrically pumped parity-time (PT)-symmetric microring laser with precise mode control, to achieve wavelength-tunable single-mode lasing with an improved mode suppression ratio. The proposed PT-symmetric laser is implemented based on a photonic integrated circuit consisting of two mutually coupled active microring resonators. By incorporating multiple semiconductor optical amplifiers in the microring resonators, the PT-symmetry condition can be achieved by a precise manipulation of the interplay between the gain and loss in the two microring resonators, and the incorporation of phase modulators in the microring resonators enables continuous wavelength tuning. Single-mode lasing at 1,554.148 nm with a sidemode suppression ratio exceeding 36 dB is demonstrated and the lasing wavelength is continuously tunable from 1,553.800 to 1,554.020 nm.

  13. Low-noise small-size microring ultrasonic detectors for high-resolution photoacoustic imaging

    PubMed Central

    Chen, Sung-Liang; Ling, Tao; Guo, L. Jay

    2011-01-01

    Small size polymer microring resonators have been exploited for photoacoustic (PA) imaging. To demonstrate the advantages of the wide acceptance angle of ultrasound detection of small size microrings, photoacoustic tomography (PAT), and delay-and-sum beamforming PA imaging was conducted. In PAT, we compared the imaging quality using different sizes of detectors with similar noise-equivalent pressures and the same wideband response: 500 μm hydrophone and 100, 60, and 40 μm microrings. The results show significantly improved imaging contrast and high resolution over the whole imaging region using smaller size detectors. The uniform high resolution in PAT imaging using 40 μm microrings indicates the potential to resolve microvasculature over a large imaging region. The improved lateral resolution of two-dimensional and three-dimensional delay-and-sum beamforming PA imaging using a synthetic array demonstrate another advantageous application of small microrings. The small microrings can also be applied to other ultrasound-related imaging applications. PMID:21639569

  14. Electro-optic Charon polymeric microring modulators.

    PubMed

    Rezzonico, Daniele; Jazbinsek, Mojca; Guarino, Andrea; Kwon, O-Pil; Günter, Peter

    2008-01-21

    We propose and demonstrate a new type of electro-optic polymeric microring resonators, where the shape of the transmission spectrum is controlled by losses and phase shifts induced at the asymmetric directional coupler between the cavity and the bus waveguide. The theoretical analysis of such Charon microresonators shows, depending on the coupler design, three different transmission characteristics: normal Lorentzian dips, asymmetric Fano resonances, and Lorentzian peaks. The combination of the active azo-stilbene based polyimide SANDM2 surrounded by the hybrid polymer Ormocomp allowed the first experimental demonstration of electro-optic modulation in Charon microresonators. The low-loss modulators (down to 0.6 dB per round trip), with a radius of 50 microm, were produced by micro-embossing and exhibit either highly asymmetric and steep Fano resonances with large 43-GHz modulation bandwidth or strong resonances with 11-dB extinction ratio. We show that Charon microresonators can lead to 1-V half wave voltage all-polymer micrometer-scale devices with larger tolerances to coupler fabrication limitations and wider modulation bandwidths than classical ring resonators.

  15. Hollow nanotubular toroidal polymer microrings.

    PubMed

    Lee, Jiyeong; Baek, Kangkyun; Kim, Myungjin; Yun, Gyeongwon; Ko, Young Ho; Lee, Nam-Suk; Hwang, Ilha; Kim, Jeehong; Natarajan, Ramalingam; Park, Chan Gyung; Sung, Wokyung; Kim, Kimoon

    2014-02-01

    Despite the remarkable progress made in the self-assembly of nano- and microscale architectures with well-defined sizes and shapes, a self-organization-based synthesis of hollow toroids has, so far, proved to be elusive. Here, we report the synthesis of polymer microrings made from rectangular, flat and rigid-core monomers with anisotropically predisposed alkene groups, which are crosslinked with each other by dithiol linkers using thiol-ene photopolymerization. The resulting hollow toroidal structures are shape-persistent and mechanically robust in solution. In addition, their size can be tuned by controlling the initial monomer concentrations, an observation that is supported by a theoretical analysis. These hollow microrings can encapsulate guest molecules in the intratoroidal nanospace, and their peripheries can act as templates for circular arrays of metal nanoparticles.

  16. Broadband nanophotonic waveguides and resonators based on epitaxial GaN thin films

    SciTech Connect

    Bruch, Alexander W.; Xiong, Chi; Leung, Benjamin; Poot, Menno; Han, Jung; Tang, Hong X.

    2015-10-05

    We demonstrate broadband, low loss optical waveguiding in single crystalline GaN grown epitaxially on c-plane sapphire wafers through a buffered metal-organic chemical vapor phase deposition process. High Q optical microring resonators are realized in near infrared, infrared, and near visible regimes with intrinsic quality factors exceeding 50 000 at all the wavelengths we studied. TEM analysis of etched waveguide reveals growth and etch-induced defects. Reduction of these defects through improved material and device processing could lead to even lower optical losses and enable a wideband photonic platform based on GaN-on-sapphire material system.

  17. Thermoelastic damping in thin microrings with two-dimensional heat conduction

    NASA Astrophysics Data System (ADS)

    Fang, Yuming; Li, Pu

    2015-05-01

    Accurate determination of thermoelastic damping (TED) is very challenging in the design of micro-resonators. Microrings are widely used in many micro-resonators. In the past, to model the TED effect on the microrings, some analytical models have been developed. However, in the previous works, the heat conduction within the microring is modeled by using the one-dimensional approach. The governing equation for heat conduction is solved only for the one-dimensional heat conduction along the radial thickness of the microring. This paper presents a simple analytical model for TED in microrings. The two-dimensional heat conduction over the thermoelastic temperature gradients along the radial thickness and the circumferential direction are considered in the present model. A two-dimensional heat conduction equation is developed. The solution of the equation is represented by the product of an assumed sine series along the radial thickness and an assumed trigonometric series along the circumferential direction. The analytical results obtained by the present 2-D model show a good agreement with the numerical (FEM) results. The limitations of the previous 1-D model are assessed.

  18. Micro-ring sensor used in the diagnosis of gastric cancer

    NASA Astrophysics Data System (ADS)

    Shi, Sichao; Cheng, Qing; Lin, Rong; Su, Da; Huang, Ying

    2016-01-01

    To find a detecting method that can be applied to the clinical screening and diagnosis, the cascaded micro-ring sensor with Vernier effect was used to distinguish gastric cancerous and normal cells. The simulation by FDTD of the cascaded microring sensor with different refractive indexes of the analyte (normal cells and gastric cancer cells) will be presented. In the simulation, with the refractive index's change Δn=0.02 for the two different analyte, the shift of sensor's resonant wavelength is 6.71nm. And the cascaded micro-ring sensor's sensitivity S is 335.5nm/RIU, and it is much larger compared to 19nm/RIU for a single ring sensor.

  19. Influences of carrier diffusion and radial mode field pattern on high speed characteristics for microring lasers

    SciTech Connect

    Lv, Xiao-Meng; Huang, Yong-Zhen Yang, Yue-De; Zou, Ling-Xiu; Long, Heng; Liu, Bo-Wen; Xiao, Jin-Long; Du, Yun

    2014-04-21

    High-speed directly modulated microlasers are potential light sources for on-chip optical interconnection and photonic integrated circuits. In this Letter, dynamic characteristics are studied for microring lasers by rate equation analysis considering radial carrier hole burning and diffusion and experimentally. The coupled modes with a wide radial field pattern and the injection current focused in the edge area of microring resonator can greatly improve the high speed response curve due to the less carrier hole burning. The small-signal response curves of a microring laser connected with an output waveguide exhibit a larger 3 dB bandwidth and smaller roll-off at low frequency than that of the microdisk laser with the same radius of 15 μm, which accords with the simulation results.

  20. Extremely high Q -factor metamaterials due to anapole excitation

    NASA Astrophysics Data System (ADS)

    Basharin, Alexey A.; Chuguevsky, Vitaly; Volsky, Nikita; Kafesaki, Maria; Economou, Eleftherios N.

    2017-01-01

    We have designed and fabricated a metamaterial consisting of planar metamolecules which exhibit unusual, almost perfect anapole behavior in the sense that the electric dipole radiation is almost canceled by the toroidal dipole one, producing thus an extremely high Q -factor at the resonance frequency. Thus we have demonstrated theoretically and experimentally that metamaterials approaching ideal anapole behavior have very high Q -factor. The size of the system, at the millimeter range, and the parasitic magnetic quadrupole radiation are the factors limiting the size of the Q -factor. In spite of the very low radiation losses the estimated local fields at the metamolecules are extremely high, of the order of 104 higher than the external incoming field.

  1. Design and investigation of a novel silicon/ferroelectric hybrid electro-optical microring modulator

    NASA Astrophysics Data System (ADS)

    Qi, Zhipeng; Hu, Guohua; Liu, Chang; Li, Lei; Yun, Binfeng; Zhang, Ruohu; Cui, Yiping

    2017-02-01

    A silicon (Si) and lanthanum-doped lead zirconium titanate (PLZT) hybrid microring modulator based on silicon-on-insulator (SOI) platform is designed theoretically and investigated numerically in this paper. The heterogeneous integration of PLZT film with Si material enables the waveguide to acquire both excellent electro-optical property and strong mode confinement capacity. Such hybrid microring modulator (100 μm in radius) has a PLZT rib-loaded cladding and is integrated with optimized tuning electrodes. The simulation results demonstrated that the Si/PLZT hybrid microring modulator could operate at 14 GHz with a relative high modulation efficiency (<0.8 V cm), which is much better than the other proposed Si/ferroelectric modulators. Meanwhile, under a driving voltage of 20 V, our modulator exhibits an extinction ratio of 32 dB at 1550.22 nm wavelength and a resonant wavelength tunability of 25 pm/V for TE mode. With these outstanding performances, the Si/PLZT hybrid microring modulator holds a great potential as a reliable on-chip device for optical communications and links.

  2. High-Q gold and silicon nitride bilayer nanostrings

    NASA Astrophysics Data System (ADS)

    Biswas, T. S.; Suhel, A.; Hauer, B. D.; Palomino, A.; Beach, K. S. D.; Davis, J. P.

    2012-08-01

    Low-mass, high-Q, silicon nitride nanostrings are at the cutting edge of nanomechanical devices for sensing applications. Here we show that the addition of a chemically functionalizable gold overlayer does not adversely affect the Q of the fundamental out-of-plane mode. Instead the device retains its mechanical responsiveness while gaining sensitivity to molecular bonding. Furthermore, differences in thermal expansion within the bilayer give rise to internal stresses that can be electrically controlled. In particular, an alternating current (AC) excites resonant motion of the nanostring. This AC thermoelastic actuation is simple, robust, and provides an integrated approach to sensor actuation.

  3. High-Q terahertz reconfigurable metamaterials using graphene

    NASA Astrophysics Data System (ADS)

    Arezoomandan, Sara; Sensale Rodriguez, Berardi

    2016-09-01

    We propose and discuss high-Q reconfigurable metamaterials based on graphene. The key components of the device are periodic concentric metallic ring resonators with interdigitated fingers, which are placed in-between the rings and provide for the large Q in the metamaterial, as well as several strategically located gaps where active graphene sheets are placed. We can easily adjust the frequency response of the metamaterial by means of varying a couple of parameters, such as the ring dimensions, number of fingers, etc., but also dynamically by means of varying conductivity in graphene.

  4. Controllable mode multistability in microring lasers.

    PubMed

    Yuan, Guohui; Wang, Zhuoran

    2013-04-22

    We investigate mode multistability, i.e. coexistence of direction bistability and wavelength bi/multistability in microring lasers (MRLs) theoretically and numerically. We derive the expressions for conditions required for mode multistable operation in microring lasers based on a nonlinear multimode model with nonlinear effects stemming from carrier density pulsation, carrier heating and spectral hole burning included. We find theoretically that lasing mode can be selected from the multistable modes by external optical injection through gain saturation, and removal of the external optical injection will not affect the stability of the established lasing mode. Numerical results on all-optical multistate flip-flop function demonstrate that switching between multistable modes can be induced by trigger signals with each states self-sustained after the removal of the trigger signals in a 50µm-radius microring laser.

  5. On-chip, high-sensitivity temperature sensors based on dye-doped solid-state polymer microring lasers

    NASA Astrophysics Data System (ADS)

    Wan, Lei; Chandrahalim, Hengky; Chen, Cong; Chen, Qiushu; Mei, Ting; Oki, Yuji; Nishimura, Naoya; Guo, L. Jay; Fan, Xudong

    2017-08-01

    We developed a chip-scale temperature sensor with a high sensitivity of 228.6 pm/°C based on a rhodamine 6G (R6G)-doped SU-8 whispering gallery mode microring laser. The optical mode was largely distributed in a polymer core layer with a 30 μm height that provided detection sensitivity, and the chemically robust fused-silica microring resonator host platform guaranteed its versatility for investigating different functional polymer materials with different refractive indices. As a proof of concept, a dye-doped hyperbranched polymer (TZ-001) microring laser-based temperature sensor was simultaneously developed on the same host wafer and characterized using a free-space optics measurement setup. Compared to TZ-001, the SU-8 polymer microring laser had a lower lasing threshold and a better photostability. The R6G-doped SU-8 polymer microring laser demonstrated greater adaptability as a high-performance temperature-sensing element. In addition to the sensitivity, the temperature resolutions for the laser-based sensors were also estimated to be 0.13 °C and 0.35 °C, respectively. The rapid and simple implementation of micrometer-sized temperature sensors that operate in the range of 31 - 43 °C enables their potential application in thermometry.

  6. All-optical flip-flop composed of a single nonlinear passive microring coupled to two straight waveguides

    NASA Astrophysics Data System (ADS)

    Bahrampour, A. R.; Mohammad Ali Mirzaee, S.; Farman, F.; Zakeri, S. S.

    2009-02-01

    Microrings can have different hysteresis characteristics at their different resonance frequencies. They can be used as a multi-hysteresis optical component. In this paper an optical D-flip-flop circuit composed of a single nonlinear passive microring coupled to two straight waveguide based on the Kerr effect is proposed. The proposed circuit can operate as an optical digital circuit which synchronizes input DATA with the CLOCK of the circuit. A simple analytical model for hysteresis design and the transient analysis of the proposed D-flip-flop are presented. According to our model, the switching time of the flip-flop is in the order of 10 ps.

  7. Silicon microring-based signal modulation for chip-scale optical interconnection

    NASA Astrophysics Data System (ADS)

    Zhang, Lin; Li, Yunchu; Song, Muping; Yang, Jeng-Yuan; Beausoleil, Raymond G.; Willner, Alan E.

    2009-06-01

    Electro-optic modulation plays a critical role in implementing space-, power- and spectrally efficient optical interconnection for high-capacity computing systems. Microring resonators exhibit a great potential to achieve compact, low power-consumption and high-speed modulators. In this paper, we briefly review our efforts on designing and analyzing the microring modulators. Three types of single-ring modulators are discussed, from device behavior to possible system impact. We then present two novel double-ring modulators in which a passive ring resonator is added, enabling higher operation speed and lower power consumption. We also describe an opportunity of introducing phase modulation data formats into the on-chip communication environment. In this paper, our emphasis is placed on linking the devices’ physics to their system performance and providing potential technical solutions to physical-layer challenges of optical interconnection.

  8. Exact Tuning of High-Q Optical Microresonators by Use of UV

    NASA Technical Reports Server (NTRS)

    Savchankov, Anaotliy; Maleki, Lute; Iltchenko, Vladimir; Handley, Timothy

    2006-01-01

    In one of several alternative approaches to the design and fabrication of a "whispering-gallery" optical microresonator of high resonance quality (high Q), the index of refraction of the resonator material and, hence, the resonance frequencies. In this approach, a microresonator structure is prepared by forming it from an ultraviolet-sensitive material. Then the structure is subjected to controlled exposure to UV light while its resonance frequencies are monitored.

  9. Silicon micro-ring tunable laser for coherent optical communication.

    PubMed

    Li, Shiyu; Zhang, Di; Zhao, Jianyi; Yang, Qi; Xiao, Xi; Hu, Shenglei; Wang, Lei; Li, Miaofeng; Tang, Xuesheng; Qiu, Ying; Luo, Ming; Yu, Shaohua

    2016-03-21

    A compact external cavity tunable laser based on a silicon hybrid micro-ring resonator is demonstrated. A theoretical model is also employed for design and analysis of the wavelength tuning performance of the device. In this model, the gain section of the device is simulated by a conventional multimode rate equation model, whereas all rest passive sections are modeled by the frequency domain method. Experimental results have shown that the output power of this device can reach 29 mW, with a linewidth less than 150 kHz. The tuning range is more than 17 nm in C-band with 60 dB side-mode-suppression-ratio (SMSR). This device shows a comparable performance with the commercial narrow linewidth laser as the source in coherent transmission systems.

  10. Squeezing the fundamental temperature fluctuations of a high-Q microresonator

    NASA Astrophysics Data System (ADS)

    Sun, Xuan; Luo, Rui; Zhang, Xi-Cheng; Lin, Qiang

    2017-02-01

    Temperature fluctuations of an optical resonator underlie a fundamental limit of its cavity stability. Here we show that the fundamental temperature fluctuations of a high-Q microresonator can be suppressed remarkably by pure optical means without cooling the device temperature. An optical wave launched into the cavity is able to produce strong photothermal backaction which dramatically suppresses the spectral intensity of temperature fluctuations and squeezes its overall level by orders of magnitude. The proposed photothermal temperature squeezing is expected to significantly improve the stability of optical resonances, with potentially profound impact on broad applications of high-Q cavities in sensing, metrology, and nonlinear and quantum optics.

  11. The electromechanical behavior of a micro-ring driven by traveling electrostatic force.

    PubMed

    Ye, Xiuqian; Chen, Yibao; Chen, Da-Chih; Huang, Kuo-Yi; Hu, Yuh-Chung

    2012-01-01

    There is no literature mentioning the electromechanical behavior of micro structures driven by traveling electrostatic forces. This article is thus the first to present the dynamics and stabilities of a micro-ring subjected to a traveling electrostatic force. The traveling electrostatic force may be induced by sequentially actuated electrodes which are arranged around the flexible micro-ring. The analysis is based on a linearized distributed model considering the electromechanical coupling effects between electrostatic force and structure. The micro-ring will resonate when the traveling speeds of the electrostatic force approach some critical speeds. The critical speeds are equal to the ratio of the natural frequencies to the wave number of the correlative natural mode of the ring. Apart from resonance, the ring may be unstable at some unstable traveling speeds. The unstable regions appear not only near the critical speeds, but also near some fractions of some critical speeds differences. Furthermore the unstable regions expand with increasing driving voltage. This article may lead to a new research branch on electrostatic-driven micro devices.

  12. Excited baryon form factors at high Q{sup 2}

    SciTech Connect

    Paul Stoler; Gary Adams; Abdellah Ahmidouch; Chris Armstrong; K. Assamagan; Steven Avery; K. Baker; Peter Bosted; Volker Burkert; Jim Dunne; Tom Eden; Rolf Ent; V. Frolov; David Gaskell; P. Gueye; Wendy Hinton; Cynthia Keppel; Wooyoung Kim; Michael Klusman; Doug Koltenuk; David Mack; Richard Madey; David Meekins; Ralph Minehart; Joseph Mitchell; Hamlet Mkrtchyan; James Napolitano; Gabriel Niculescu; Ioana Niculescu; Mina Nozar; John Price; Vardan Tadevosyan; Liguang Tang; Michael Witkowski; Stephen Wood

    1998-05-01

    The role of resonance electroproduction at high Q{sup 2} is discussed in the context of exclusive reactions, as well as the alternative theoretical models which are proposed to treat exclusive reactions in the few GeV{sup 2}/c{sup 2} region of momentum transfer. Jefferson Lab experiment 94-014, which measured the excitation of the Delta (1232) and S{sub 11}(1535) via the reactions p(e,e{sup '}p)pi{sup 0} and p(e,e{sup '}p)eta respectively at Q{sup 2} {approx} 2.8 and 4 GeV{sup 2}/c{sup 2} is described, and the state of analysis reported.

  13. Twin photon pairs in a high-Q silicon microresonator

    NASA Astrophysics Data System (ADS)

    Rogers, Steven; Lu, Xiyuan; Jiang, Wei C.; Lin, Qiang

    2015-07-01

    We report the generation of high-purity twin photon pairs through cavity-enhanced non-degenerate four-wave mixing (FWM) in a high-Q silicon microdisk resonator. Twin photon pairs are created within the same cavity mode and are consequently expected to be identical in all degrees of freedom. The device is able to produce twin photons at telecommunication wavelengths with a pair generation rate as large as (3.96 ± 0.03) × 105 pairs/s, within a narrow bandwidth of 0.72 GHz. A coincidence-to-accidental ratio of 660 ± 62 was measured, the highest value reported to date for twin photon pairs, at a pair generation rate of (2.47 ± 0.04) × 104 pairs/s. Through careful engineering of the dispersion matching window, we have reduced the ratio of photons resulting from degenerate FWM to non-degenerate FWM to less than 0.15.

  14. Excited baryon form factors at high Q{sup 2}

    SciTech Connect

    Stoler, Paul; Adams, G.; Frolov, V.; Klusman, M.; Napolitano, J.; Nozar, M.; Price, J.; Stoler, P.; Witkowski, M.; Ahmidouch, A.; Assamagan, K.; Avery, S.; Baker, K.; Eden, T.; Gueye, P.; Hinton, W.; Keppel, C.; Madey, R.; Niculescu, G.; Niculescu, I.

    1997-05-20

    The role of resonance electroproduction at high Q{sup 2} is discussed in the context of exclusive reactions, as well as the alternative theoretical models which are proposed to treat exclusive reactions in the few GeV{sup 2}/c{sup 2} region of momentum transfer. Jefferson Lab experiment 94-014, which measured the excitation of the {delta}(1232) and S{sub 11}(1535) via the reactions p(e,e{sup '}p){pi}{sup 0} and p(e,e{sup '}p){eta} respectively at Q{sup 2}{approx}2.8 and 4 GeV{sup 2}/c{sup 2} is described, and the state of analysis reported.

  15. High Q BPS Monopole Bags are Urchins

    NASA Astrophysics Data System (ADS)

    Evslin, Jarah; Gudnason, Sven Bjarke

    2014-01-01

    It has been known for 30 years that 't Hooft-Polyakov monopoles of charge Q greater than one cannot be spherically symmetric. Five years ago, Bolognesi conjectured that, at some point in their moduli space, BPS monopoles can become approximately spherically symmetric in the high Q limit. In this paper, we determine the sense in which this conjecture is correct. We consider an SU(2) gauge theory with an adjoint scalar field, and numerically find configurations with Q units of magnetic charge and a mass which is roughly linear in Q, for example, in the case Q = 81 we present a configuration whose energy exceeds the BPS bound by about 54%. These approximate solutions are constructed by gluing together Q cones, each of which contains a single unit of magnetic charge. In each cone, the energy is largest in the core, and so a constant energy density surface contains Q peaks and thus resembles a sea urchin.

  16. Ultra-high Q sphere-like cavities for cascaded stimulated Brillouin lasing

    NASA Astrophysics Data System (ADS)

    Che, Kaijun; Zhang, Pan; Guo, Changlei; Tang, Deyu; Ren, Changyan; Xu, Huiying; Luo, Zhengqian; Cai, Zhiping

    2017-03-01

    High Q microsphere optical cavity is usually fabricated from a single mode fiber. Here, we propose a new method to fabricate sphere-like cavity by melting the tip of rotating quartz-rod with a CO2 laser. The cavities with diameter from 200 μm to 700 μm and resonant Q factors above 108 are obtained. Due to the rich resonances of the sphere-like cavity, up to 15-order cascaded stimulated Brillouin lasings(SBL) near 1.55 μm are observed in a cavity with a diameter of 760 μm by simply tuning the pump wavelength to a finely-selected resonance. We wish the ultra-high Q cavities with rich resonances and bulk rod mount can have practical applications in nonlinear optics and microwave photonics as an optical component.

  17. Fabrication of high-Q lithium niobate microresonators using femtosecond laser micromachining

    PubMed Central

    Lin, Jintian; Xu, Yingxin; Fang, Zhiwei; Wang, Min; Song, Jiangxin; Wang, Nengwen; Qiao, Lingling; Fang, Wei; Cheng, Ya

    2015-01-01

    We report on fabrication of high-Q lithium niobate (LN) whispering-gallery-mode (WGM) microresonators suspended on silica pedestals by femtosecond laser direct writing followed by focused ion beam (FIB) milling. The micrometer-scale (diameter ~82 μm) LN resonator possesses a Q factor of ~2.5 × 105 around 1550 nm wavelength. The combination of femtosecond laser direct writing with FIB enables high-efficiency, high-precision nanofabrication of high-Q crystalline microresonators. PMID:25627294

  18. High-Q microresonators as lasing elements for silicon photonics

    NASA Astrophysics Data System (ADS)

    Borselli, Matthew

    Although the concept of constructing active optical waveguides in crystalline silicon has existed for over twenty years, it is only in the past few years that silicon photonics has been given serious attention as a, displacing technology. Fueled by the predicted saturation of "Moore's Law" within the next decade, universities and industries from all over the world are exploring the possibilities of creating truly integrated silicon opto-electronic devices in a cost effective manner. Some of the most promising silicon photonics technologies are chip-to-chip and intra-chip optical interconnects. Now that compact high-speed modulators in silicon have been achieved, the limiting factor in the widespread adoption of optical interconnects is the lack of practical on-chip optical sources. These sources are critical for the generation of the many wavelengths of light necessary for high-speed communication between the logical elements between and within microprocessors. Unfortunately, crystalline silicon is widely known as a poor emitter because of its indirect bandgap. This thesis focuses on the many challenges in generating silicon-based laser sources. As most CMOS compatible gain materials possess at most 1 dB/cm of gain, much of our work has been devoted to minimizing the optical losses in silicon optical microresonators. Silicon microdisk resonators fabricated from silicon-on-insulator wafers were employed to study and minimize the different sources of scattering and absorption present in high-index contrast Si microcavities. These microdisks supported whispering-gallery modes with quality factors as high as 5 x 106, close to the bulk limit of lightly doped silicon wafers. An external silica fiber taper probe was developed to test the microcavities in a rapid wafer-scale manner. Analytic theory and numerical simulation aided in the optimization of the cavity design and interpretation of experimental results. After successfully developing surface chemistry treatments

  19. High-Q plasmonic bottle microresonator

    NASA Astrophysics Data System (ADS)

    Mohd Nasir, M. Narizee; Ding, Ming; Murugan, G. Senthil; Zervas, Michalis N.

    2014-03-01

    In this paper, we demonstrate a hybrid plasmonic bottle microresonator (PBMR) which supports whispering gallery modes (WGMs) along with surface plasmon waves (SPWs) for high performance optical sensor applications. The BMR was fabricated through "soften-and-compress" technique with a thin gold layer deposited on top of the resonator. A polarization-resolved measurement was set-up in order to fully characterize the fabricated PBMR. Initially, the uncoated BMR with waist diameter of 181 μm, stem diameter of 125 μm and length of 400 μm was fabricated and then gold film was deposited on the surface. Due to surface curvature, the gold film covering half of the BMR had a characteristic meniscus shape and maximum thickness of 30 nm. The meniscus provides appropriately tapered edges which facilitate the adiabatic transformation of BMR WGMs to SPWs and vice versa. This results in low transition losses, which combined with partially-metal-coated resonator, can result in high hybrid-PBMR Q's. The transmission spectra of the hybrid PBMR are dramatically different to the original uncoated BMR. Under TE(TM) excitation, the PBMR showed composite resonances with Q of ~2100(850) and almost identical ~ 3 nm FSR. We have accurately fitted the observed transmission resonances with Lorentzian-shaped curves and showed that the TE and TM excitations are actually composite resonances comprise of two and three partially overlapping resonances with Q's in excess of 2900 and 2500, respectively. To the best of our knowledge these are the highest Qs observed in plasmonic microcavities.

  20. Telecom-band degenerate-frequency photon pair generation in silicon microring cavities.

    PubMed

    Guo, Yuan; Zhang, Wei; Dong, Shuai; Huang, Yidong; Peng, Jiangde

    2014-04-15

    In this Letter, telecom-band degenerate-frequency photon pairs are generated in a specific mode of a silicon microring cavity by the nondegenerate spontaneous four-wave mixing (SFWM) process, under two continuous-wave pumps at resonance wavelength of two different cavity modes. The ratio of coincidence to accidental coincidence is up to 100 under a time bin width of 5 ns, showing their characteristics of quantum correlation. Their quantum interference in balanced and unbalanced Mach-Zehnder interferometers is investigated theoretically and experimentally, and the results show potential in quantum metrology and quantum information.

  1. Organic printed photonics: From microring lasers to integrated circuits.

    PubMed

    Zhang, Chuang; Zou, Chang-Ling; Zhao, Yan; Dong, Chun-Hua; Wei, Cong; Wang, Hanlin; Liu, Yunqi; Guo, Guang-Can; Yao, Jiannian; Zhao, Yong Sheng

    2015-09-01

    A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 10(5), which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices.

  2. Organic printed photonics: From microring lasers to integrated circuits

    PubMed Central

    Zhang, Chuang; Zou, Chang-Ling; Zhao, Yan; Dong, Chun-Hua; Wei, Cong; Wang, Hanlin; Liu, Yunqi; Guo, Guang-Can; Yao, Jiannian; Zhao, Yong Sheng

    2015-01-01

    A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 105, which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices. PMID:26601256

  3. Twin photon pairs in a high-Q silicon microresonator

    SciTech Connect

    Rogers, Steven; Lu, Xiyuan; Jiang, Wei C.; Lin, Qiang

    2015-07-27

    We report the generation of high-purity twin photon pairs through cavity-enhanced non-degenerate four-wave mixing (FWM) in a high-Q silicon microdisk resonator. Twin photon pairs are created within the same cavity mode and are consequently expected to be identical in all degrees of freedom. The device is able to produce twin photons at telecommunication wavelengths with a pair generation rate as large as (3.96 ± 0.03) × 10{sup 5} pairs/s, within a narrow bandwidth of 0.72 GHz. A coincidence-to-accidental ratio of 660 ± 62 was measured, the highest value reported to date for twin photon pairs, at a pair generation rate of (2.47 ± 0.04) × 10{sup 4} pairs/s. Through careful engineering of the dispersion matching window, we have reduced the ratio of photons resulting from degenerate FWM to non-degenerate FWM to less than 0.15.

  4. Athermal optical waveguide microring biosensor with intensity interrogation

    NASA Astrophysics Data System (ADS)

    Han, Xiuyou; Shao, Yuchen; Han, Xiaonan; Lu, Zhili; Wu, Zhenlin; Teng, Jie; Ren, Jun; Zhao, Mingshan

    2015-12-01

    The temperature sensitivity of optical waveguide microring (MR) is the critical factor to influence the performance of MR-based biosensor. An athermal MR-based biosensor with intensity interrogation is proposed and analyzed. The integrative biosensor chip is composed of sensing unit MR and interrogation unit Mach-Zehnder interferometer (MZI) with the same temperature sensitivity. The resonant wavelength shift of MR by temperature change is equal to the center wavelength shift of interrogation curve of MZI which cancel with each other during interrogation process. The polymer based integrative biosensor chip is designed and investigated. The simulation results show that the temperature sensitivity of the polymer waveguide biosensor is smaller than 1 pm/K with the temperature change between -10 K to 20 K relative to the reference temperature 20 °C and refractive index change from 0 to 0.05. The intensity interrogation method utilizing the power ratio between the two output ports of MZI has the flexibility of selecting large linear range and high resolution and is immune to output power fluctuations of the light source.

  5. Tunable high-q superconducting notch filter

    DOEpatents

    Pang, C.S.; Falco, C.M.; Kampwirth, R.T.; Schuller, I.K.

    1979-11-29

    A superconducting notch filter is made of three substrates disposed in a cryogenic environment. A superconducting material is disposed on one substrate in a pattern of a circle and an annular ring connected together. The second substrate has a corresponding pattern to form a parallel plate capacitor and the second substrate has the circle and annular ring connected by a superconducting spiral that forms an inductor. The third substrate has a superconducting spiral that is placed parallel to the first superconducting spiral to form a transformer. Relative motion of the first substrate with respect to the second is effected from outside the cryogenic environment to vary the capacitance and hence the frequency of the resonant circuit formed by the superconducting devices.

  6. Microfiber coil resonator and waveguide

    NASA Astrophysics Data System (ADS)

    Sumetsky, Mikhail

    2005-04-01

    The recently suggested self-coupling microfiber coil optical resonator (COR) is a simplest functional element for the future microfiber-based photonics. It could be created by wrapping a microfiber on a dielectric rod with smaller refractive index. It is feasible that COR, which is produced from a drawn optical microfiber, will not suffer from surface roughness as e.g. the lithographically fabricated 2D microrings. Therefore, COR may have extremely small losses and generate high-Q resonances. In this paper, the theoretical study of the basic electromagnetic properties of the uniform self-coupling COR with N turns is presented. The eigenmodes of COR, which are qualitatively different from the modes of the known types of resonators, exist for the discrete values of the dimensionless coupling parameter K=κS > ½, where κ is the coupling coefficient between adjacent turns and S is the length of a turn. The spatial variation of the mode amplitudes does not have the wavelength scale oscillations and has no correlation with the period of COR, S. For certain series of K, the free spectrum range of COR is independent of the number of turns N and COR behaves similar to a single ring resonator. For N-->∞, the microfiber coil optical waveguide (COW) has a simple dispersion relation implying the absence of stop bands. The value K = ½ corresponds to the crossover between two regimes of propagation: with and without zeroing of the group velocity. At the crossover, the dispersion relation of COW has inflexion points wherein the group velocity and the inversed group velocity dispersion simultaneously become zero.

  7. High-Q filters with complete transports using quasiperiodic rings with spin-orbit interaction

    SciTech Connect

    Qiu, R. Z.; Chen, C. H.; Tsao, C. W.; Hsueh, W. J.

    2014-09-15

    A high Q filter with complete transports is achieved using a quasiperiodic Thue-Morse array of mesoscopic rings with spin-orbit interaction. As the generation order of the Thue-Morse array increases, not only does the Q factor of the resonance peak increase exponentially, but the number of sharp resonance peaks also increases. The maximum Q factor for the electronic filter of a Thue-Morse array is much greater than that in a periodic array, for the same number of the rings.

  8. High-Q photonic crystal cavities in all-semiconductor photonic crystal heterostructures

    NASA Astrophysics Data System (ADS)

    Bushell, Z. L.; Florescu, M.; Sweeney, S. J.

    2017-06-01

    Photonic crystal cavities enable the realization of high Q-factor and low mode-volume resonators, with typical architectures consisting of a thin suspended periodically patterned layer to maximize confinement of light by strong index guiding. We investigate a heterostructure-based approach comprising a high refractive index core and lower refractive index cladding layers. While confinement typically decreases with decreasing index contrast between the core and cladding layers, we show that, counterintuitively, due to the confinement provided by the photonic band structure in the cladding layers, it becomes possible to achieve Q factors >104 with only a small refractive index contrast. This opens up opportunities for implementing high-Q factor cavities in conventional semiconductor heterostructures, with direct applications to the design of electrically pumped nanocavity lasers using conventional fabrication approaches.

  9. Integrated finely tunable microring laser on silicon

    NASA Astrophysics Data System (ADS)

    Liang, D.; Huang, X.; Kurczveil, G.; Fiorentino, M.; Beausoleil, R. G.

    2016-11-01

    Large-scale computer installations are severely limited by network-bandwidth constraints and energy costs that arise from architectural designs originally based on copper interconnects. Wavelength-division multiplexed (WDM) photonic links can increase the network bandwidth but are sensitive to environmental perturbations and manufacturing imperfections that can affect the precise emission wavelength and output power of laser transmitters. Here, we demonstrate a new design of a three-terminal hybrid III-V-on-silicon laser that integrates a metal-oxide-semiconductor (MOS) capacitor into the laser cavity. The MOS capacitor makes it possible to introduce the plasma-dispersion effect and thus change the laser modal refractive index and free-carrier absorption (FCA) loss to tune the laser wavelength and output power, respectively. The approach enables a highly energy efficient method to tune the output power and wavelength of microring lasers, with future prospects for high-speed, chirp-free direct laser modulation. The concept is potentially applicable to other diode laser platforms.

  10. Optical whispering-gallery mode resonators for applications in optical communication and frequency control

    NASA Astrophysics Data System (ADS)

    Grutter, Karen Esther

    High quality factor (Q) optical whispering gallery mode resonators are a key component in many on-chip optical systems, such as delay lines, modulators, and add-drop filters. They are also a convenient, compact structure for studying optomechanical interactions on-chip. In all these applications, optical Q is an important factor for high performance. For optomechanical reference oscillators in particular, high mechanical Q is also necessary. Previously, optical microresonators have been made in a wide variety of materials, but it has proven challenging to demonstrate high optical Q and high mechanical Q in a single, integrated device. This work demonstrates a new technique for achieving high optical Q on chip, a fully-integrated tunable filter with ultra-narrow minimum bandwidth, and the effect of material choice and device design on optical Q, mechanical Q and phase noise in microring optomechanical oscillators. To achieve a high optical Q, phosphosilicate glass (PSG) is studied as a resonator material. The low melting point of PSG enables wafer-scale reflow, which reduces sidewall roughness without significantly changing lithographically-defined dimensions. With this process, optical Qs up to 1.5 x 10. 7 are achieved, overten times higher than typical silicon optical resonators. These high-Q PSG resonators are then integrated with MEMS-actuated waveguides in a tunable-bandwidth filter. Due to the high Q of the PSG resonator, this device has a best-to-date minimum bandwidth of 0.8 GHz, with a tuning range of 0.8 to 8.5GHz. Finally, microring optomechanical oscillators (OMOs) in PSG, stoichiometric silicon nitride, and silicon are fabricated, and their performance is compared after characterization via a tapered optical fiber in vacuum. The silicon nitride device has the best performance, with a mechanical Q of more than 1 x 10. 4and record-breaking OMO phase noise of -102 dBc/Hz at a 1 kHz offset from a 72 MHz carrier.

  11. RF inductor has high Q, is stable at higher temperatures

    NASA Technical Reports Server (NTRS)

    Wiler, E. M.

    1967-01-01

    Encapsulated RF inductor with an insulated coil has a high Q and remains stable for long periods of time at high temperatures. The coil is wound on a core and both are encapsulated in an epoxy resin. Two terminals are soldered to the coil.

  12. Observation of the fundamental Nyquist noise limit in an ultra-high Q-factor cryogenic bulk acoustic wave cavity

    SciTech Connect

    Goryachev, Maxim Ivanov, Eugene N.; Tobar, Michael E.; Kann, Frank van; Galliou, Serge

    2014-10-13

    Thermal Nyquist noise fluctuations of high-Q bulk acoustic wave cavities have been observed at cryogenic temperatures with a DC superconducting quantum interference device amplifier. High Q modes with bandwidths of few tens of milliHz produce thermal fluctuations with a signal-to-noise ratio of up to 23 dB. The estimated effective temperature from the Nyquist noise is in good agreement with the physical temperature of the device, confirming the validity of the equivalent circuit model and the non-existence of any excess resonator self-noise. The measurements also confirm that the quality factor remains extremely high (Q > 10{sup 8} at low order overtones) for very weak (thermal) system motion at low temperatures, when compared to values measured with relatively strong external excitation. This result represents an enabling step towards operating such a high-Q acoustic device at the standard quantum limit.

  13. High Q value Quartz Tuning Fork in Vacuum as a Potential Thermometer in Millikelvin Temperature Range

    NASA Astrophysics Data System (ADS)

    Človečko, M.; Grajcar, M.; Kupka, M.; Neilinger, P.; Rehák, M.; Skyba, P.; Vavrek, F.

    2017-06-01

    The results of a newly developed pulse-demodulation (P-D) technique introduced to determine the resonant characteristics of a high Q value quartz tuning forks in vacuum and millikelvin temperature range are presented. Applying P-D technique to a standard 32 kHz quartz tuning fork with extremely low excitation energy of the order of a few femtojoules, we were able to measure the resonance frequency of the fork's decay signal with resolution better than 10 μ Hz. Using this highly sensitive measurement technique, we found a continuous and reproducible temperature dependence of the tuning fork's resonance frequency in the millikelvin temperature range. The observed dependence suggests a potential application for the quartz tuning forks to be used as thermometers in the millikelvin temperature range. We also discuss the physical origin of the observed phenomenon.

  14. Dispersion engineering of high-Q silicon microresonators via thermal oxidation

    SciTech Connect

    Jiang, Wei C.; Zhang, Jidong; Usechak, Nicholas G.; Lin, Qiang

    2014-07-21

    We propose and demonstrate a convenient and sensitive technique for precise engineering of group-velocity dispersion in high-Q silicon microresonators. By accurately controlling the surface-oxidation thickness of silicon microdisk resonators, we are able to precisely manage the zero-dispersion wavelength, while simultaneously further improving the high optical quality of our devices, with the optical Q close to a million. The demonstrated dispersion management allows us to achieve parametric generation with precisely engineerable emission wavelengths, which shows great potential for application in integrated silicon nonlinear and quantum photonics.

  15. Inverse design of high-Q wave filters in two-dimensional phononic crystals by topology optimization.

    PubMed

    Dong, Hao-Wen; Wang, Yue-Sheng; Zhang, Chuanzeng

    2017-04-01

    Topology optimization of a waveguide-cavity structure in phononic crystals for designing narrow band filters under the given operating frequencies is presented in this paper. We show that it is possible to obtain an ultra-high-Q filter by only optimizing the cavity topology without introducing any other coupling medium. The optimized cavity with highly symmetric resonance can be utilized as the multi-channel filter, raising filter and T-splitter. In addition, most optimized high-Q filters have the Fano resonances near the resonant frequencies. Furthermore, our filter optimization based on the waveguide and cavity, and our simple illustration of a computational approach to wave control in phononic crystals can be extended and applied to design other acoustic devices or even opto-mechanical devices.

  16. Nanopatterned protein microrings from a diatom that direct silica morphogenesis

    PubMed Central

    Scheffel, André; Poulsen, Nicole; Shian, Samuel; Kröger, Nils

    2011-01-01

    Diatoms are eukaryotic microalgae that produce species-specifically structured cell walls made of SiO2 (silica). Formation of the intricate silica structures of diatoms is regarded as a paradigm for biomolecule-controlled self-assembly of three-dimensional, nano- to microscale-patterned inorganic materials. Silica formation involves long-chain polyamines and phosphoproteins (silaffins and silacidins), which are readily soluble in water, and spontaneously form dynamic supramolecular assemblies that accelerate silica deposition and influence silica morphogenesis in vitro. However, synthesis of diatom-like silica structure in vitro has not yet been accomplished, indicating that additional components are required. Here we describe the discovery and intracellular location of six novel proteins (cingulins) that are integral components of a silica-forming organic matrix (microrings) in the diatom Thalassiosira pseudonana. The cingulin-containing microrings are specifically associated with girdle bands, which constitute a substantial part of diatom biosilica. Remarkably, the microrings exhibit protein-based nanopatterns that closely resemble characteristic features of the girdle band silica nanopatterns. Upon the addition of silicic acid the microrings become rapidly mineralized in vitro generating nanopatterned silica replicas of the microring structures. A silica-forming organic matrix with characteristic nanopatterns was also discovered in the diatom Coscinodiscus wailesii, which suggests that preassembled protein-based templates might be general components of the cellular machinery for silica morphogenesis in diatoms. These data provide fundamentally new insight into the molecular mechanisms of biological silica morphogenesis, and may lead to the development of self-assembled 3D mineral forming protein scaffolds with designed nanopatterns for a host of applications in nanotechnology. PMID:21300899

  17. Applications of High-Q Microresonators in Cavity Optomechanics and Nonlinear Photonics

    NASA Astrophysics Data System (ADS)

    Jiang, Wei C.

    Optical microresonators confining light to small volumes are indispensable for a great variety of studies and applications. This thesis is devoted to a study of cavity optomechanical and nonlinear optical phenomena in high-Q microresonators with different materials and structures. Based on that, it proposes and demonstrates several novel schemes and device platforms that exhibit great potential for various applications ranging from frequency metrology and quantum photonics, to information processing and sensing. The thesis starts with a demonstration of a high-frequency (above 1 GHz) regenerative optomechanical oscillator based on a 2-mum-radius high-Q silicon microdisk resonator in the silicon-on-insulator platform with an ultra-low threshold pump power at room temperature and atmosphere. It then continues to explore the cavity optomechanics in single-crystal lithium niobate. A compact lithium niobate microdisk optomechanical resonator with high optical and mechanical qualities, large optomechanical coupling, and high mechanical frequency is achieved, enabling the demonstration of regenerative oscillation in the ambience. Meanwhile, I propose and investigate a novel approach for single molecule detection that utilizes the optical spring effect in a high-Q coherent optomechanical oscillator to dramatically enhance the sensing resolution by orders of magnitude compared with conventional resonator-based approaches. In particular, a high-Q silica microsphere is employed to experimentally demonstrate the detection of single Bovine Serum Albumin proteins with a molecular weight of 66 kDalton at a signal-to-noise ratio of 16.8. On the other hand, the thesis focuses on the theoretical and experimental investigation of the generation of high-purity bright photon pairs in a silicon microdisk based on the cavity enhanced four-wave mixing. The device is able to produce multiple photon pairs at different wavelengths in the telecom band with a high spectral brightness of 6.24 x

  18. Novel high-Q modes in thick 2D photonic crystal slabs

    NASA Astrophysics Data System (ADS)

    Pugh, J. R.; Ho, Y.-L. D.; Engin, E.; Railton, C.; Rarity, J. G.; Cryan, M. J.

    2013-03-01

    The periodic nature of photonic crystals (PCs) (Yablonovitch 1987 Phys. Rev. Lett. 58 2059-62 John 1987 Phys. Rev. Lett. 58 2486-9) has been extensively exploited for the past quarter of a century using photonic bandgap (PBG) effects to manipulate photons in engineered electromagnetic structures. Structures such as photonic crystal nanocavities are widely considered to be key in realizing future nanoscale optoelectronic devices. These cavities are capable of creating resonant modes with high-quality factor (Q) and small mode volume, in other words a large Purcell factor (Purcell 1946 Phys. Rev. 69 681), and have been widely researched in the two-dimensional photonic crystal slab (PCS) defect cavity configuration (Painter et al 1999 J. Opt. Soc. Am. B 16 275-85). Here, we demonstrate for the first time how three confinement mechanisms are thought to coincide to give rise to a high-Q resonance for a slab containing a modified L3 defect where the slab thickness is such that the guiding in the slab is no longer single moded (Tandaechanurat et al 2008 Opt. Express 16 448-55). This is in contrast to the conventional design approach, where the PCS thickness is chosen to be of the order of half a lattice constant to ensure that a PBG exists to confine cavity modes strongly within the slab (Painter et al 1999 J. Opt. Soc. Am. B 16 275-85 Johnson et al 1999 Phys. Rev. B 60 5751-8 Khankhoje et al 2010 Nanotechnology 21 065202). These newly identified high-Q modes can be important in terms of the fabrication of slabs and other devices such as vertical pillars since they allow high-Q factors in thicker and more fabrication tolerant geometries.

  19. Localized high-Q modes in conical microcavities

    NASA Astrophysics Data System (ADS)

    Lin, Xing; Fang, Wei

    2016-12-01

    We carry out three-dimensional (3D) numerical simulation on a conical microcavity with a half-angle of 11 degree, where there exists high-Q modes by introducing a thin high refractive index film on a conical surface. Our study reveals that, rather than the surface profile of the microcavity, the effective radius plays crucial role in whether the cavity may support localized modes. Specifically, the change of high refractive index film thickness creates an additional angular momentum barrier, so that the conical microcavity may sustain localized high-Q modes. Our study offers a new degree of freedom to control the properties of 3D microcavities, which is useful for microlaser or sensor applications.

  20. Label-free virus detection using silicon photonic microring resonators

    USDA-ARS?s Scientific Manuscript database

    Viruses represent a continual threat to humans through a number of mechanisms, which include disease, bioterrorism, and destruction of both plant and animal food resources. Many contemporary techniques used for the detection of viruses and viral infections suffer from limitations such as the need fo...

  1. Measuring the Charge of a Single Dielectric Nanoparticle Using a High-Q Optical Microresonator

    NASA Astrophysics Data System (ADS)

    Chen, You-Ling; Jin, Wei-Liang; Xiao, Yun-Feng; Zhang, Xuming

    2016-10-01

    Measuring the charge of a nanoparticle is of great importance in many fields including optics, astronomy, biochemistry, atmospheric science, environmental engineering, and dusty plasma. Here, we propose to use a high-Q whispering-gallery-mode (WGM) optical microresonator to detect the surface and bulk charge of a dielectric nanoparticle. Because of the modification of nanoparticle conductivity induced by the surplus electrons, both the coupling strength between the nanoparticle and the WGM and the dissipation changes compared with the case of a neutral nanoparticle. The charge density can be inferred from the transmission spectrum of the WGM microresonator. By monitoring the mode splitting, the linewidth broadening or the resonance dip value of the transmission spectrum, surface (bulk) electron density as low as 0.007 nm-2 (0.001 nm-3) can be detected for nanoparticles with negative (positive) electron affinity. The high sensitivity is attributed to the ultranarrow resonance linewidth and small mode volume of the microresonator.

  2. Selective tuning of high-Q silicon photonic crystal nanocavities via laser-assisted local oxidation.

    PubMed

    Chen, Charlton J; Zheng, Jiangjun; Gu, Tingyi; McMillan, James F; Yu, Mingbin; Lo, Guo-Qiang; Kwong, Dim-Lee; Wong, Chee Wei

    2011-06-20

    We examine the cavity resonance tuning of high-Q silicon photonic crystal heterostructures by localized laser-assisted thermal oxidation using a 532 nm continuous wave laser focused to a 2.5 μm radius spot-size. The total shift is consistent with the parabolic rate law. A tuning range of up to 8.7 nm is achieved with ∼ 30 mW laser powers. Over this tuning range, the cavity Qs decreases from 3.2×10(5) to 1.2×10(5). Numerical simulations model the temperature distributions in the silicon photonic crystal membrane and the cavity resonance shift from oxidation.

  3. Realization of high-Q/V photonic crystal cavities defined by an effective Aubry-André-Harper bichromatic potential

    NASA Astrophysics Data System (ADS)

    Simbula, A.; Schatzl, M.; Zagaglia, L.; Alpeggiani, F.; Andreani, L. C.; Schäffler, F.; Fromherz, T.; Galli, M.; Gerace, D.

    2017-05-01

    We report on the realization of high-Q/V photonic crystal cavities in thin silicon membranes, with resonances around 1.55 μm wavelength. The cavity designs are based on a recently proposed photonic crystal implementation of the Aubry-André-Harper bichromatic potential, defined from the superposition of two one-dimensional lattices with a non-integer ratio between their periodicity constants. In photonic crystal nanocavities, this confinement mechanism is such that optimized figures of merit can be straightforwardly achieved, in particular an ultra-high-Q factor and diffraction-limited mode volume. Several silicon membrane photonic crystal nanocavities have been realized with measured Q-factors in the 1 × 106 range, as evidenced by resonant scattering. The generality of the proposed designs and their easy implementation and scalability make these results particularly interesting for realizing highly performing photonic nanocavities on different material platforms and operational wavelengths.

  4. High-Q contacted ring microcavities with scatterer-avoiding “wiggler” Bloch wave supermode fields

    SciTech Connect

    Liu, Yangyang Popović, Miloš A.

    2014-05-19

    High-Q ring resonators with contacts to the waveguide core provide a versatile platform for various applications in chip-scale optomechanics, thermo-, and electro-optics. We propose and demonstrate azimuthally periodic contacted ring resonators based on multi-mode Bloch matching that support contacts on both the inner and outer radius edges with small degradation to the optical quality factor (Q). Radiative coupling between degenerate modes of adjacent radial spatial order leads to imaginary frequency (Q) splitting and a scatterer avoiding high-Q “wiggler” supermode field. We experimentally measure Qs up to 258 000 in devices fabricated in a silicon device layer on buried oxide undercladding and up to 139 000 in devices fully suspended in air using an undercut step. Wiggler supermodes are true modes of the microphotonic system that offer additional degrees of freedom in electrical, thermal, and mechanical design.

  5. Excitability in semiconductor microring lasers: Experimental and theoretical pulse characterization

    SciTech Connect

    Gelens, L.; Coomans, W.; Van der Sande, G.; Verschaffelt, G.; Mashal, L.; Beri, S.; Danckaert, J.

    2010-12-15

    We characterize the operation of semiconductor microring lasers in an excitable regime. Our experiments reveal a statistical distribution of the characteristics of noise-triggered optical pulses that is not observed in other excitable systems. In particular, an inverse correlation exists between the pulse amplitude and duration. Numerical simulations and an interpretation in an asymptotic phase space confirm and explain these experimentally observed pulse characteristics.

  6. Anisotropic phantom to calibrate high-q diffusion MRI methods

    NASA Astrophysics Data System (ADS)

    Komlosh, M. E.; Benjamini, D.; Barnett, A. S.; Schram, V.; Horkay, F.; Avram, A. V.; Basser, P. J.

    2017-02-01

    A silicon oil-filled glass capillary array is proposed as an anisotropic diffusion MRI phantom. Together with a computational/theoretical pipeline these provide a gold standard for calibrating and validating high-q diffusion MRI experiments. The phantom was used to test high angular resolution diffusion imaging (HARDI) and double pulsed-field gradient (d-PFG) MRI acquisition schemes. MRI-based predictions of microcapillary diameter using both acquisition schemes were compared with results from optical microscopy. This phantom design can be used for quality control and quality assurance purposes and for testing and validating proposed microstructure imaging experiments and the processing pipelines used to analyze them.

  7. Micromachined high Q inductors for high-frequency applications

    NASA Astrophysics Data System (ADS)

    Park, Jae Y.; Allen, Mark G.

    1998-09-01

    To meet requirements in mobile communication and microwave integrated circuits, miniaturization of the inductive components that many of these systems require is of key importance. At present, active circuitry is used which simulates inductor performance and which has high Q-factor and inductance; however, such circuitry has higher power consumption and higher potential for noise injection than passive inductive components. An alternate approach is to fabricate integrated inductors, in which lithographic techniques are used to pattern an inductor directly on a substrate or a chip. However, integrated inductors can suffer from low Q-factor and high parasitic effects due to substrate proximity. To expand the applications of integrated inductors, these characteristics must be improved. High Q integrated spiral inductors are investigated using olymer/metal multilayer processing techniques and surface micromachining techniques. These inductors have spiral geometry with an air core and a large air gap (4Oim height) between the coils and the substrate (to reduce substrate capacitance), and thick, highly conductive electroplated copper conductor lines (to increase the quality factor). Various inductor geometries are investigated by designing and fabricating several inductors with differing core areas and numbers of turns. The fabricated inductors have a Q-factor of 40-75 at 300-700 MHz and an inductance at these frequencies between 30-7OnH.

  8. The combination of high Q factor and chirality in twin cavities and microcavity chain.

    PubMed

    Song, Qinghai; Zhang, Nan; Zhai, Huilin; Liu, Shuai; Gu, Zhiyuan; Wang, Kaiyang; Sun, Shang; Chen, Zhiwei; Li, Meng; Xiao, Shumin

    2014-09-29

    Chirality in microcavities has recently shown its bright future in optical sensing and microsized coherent light sources. The key parameters for such applications are the high quality (Q) factor and large chirality. However, the previous reported chiral resonances are either low Q modes or require very special cavity designs. Here we demonstrate a novel, robust, and general mechanism to obtain the chirality in circular cavity. By placing a circular cavity and a spiral cavity in proximity, we show that ultra-high Q factor, large chirality, and unidirectional output can be obtained simultaneously. The highest Q factors of the non-orthogonal mode pairs are almost the same as the ones in circular cavity. And the co-propagating directions of the non-orthogonal mode pairs can be reversed by tuning the mode coupling. This new mechanism for the combination of high Q factor and large chirality is found to be very robust to cavity size, refractive index, and the shape deformation, showing very nice fabrication tolerance. And it can be further extended to microcavity chain and microcavity plane. We believe that our research will shed light on the practical applications of chirality and microcavities.

  9. Hollow plasmonic high Q-factor absorber for bio-sensing in mid-infrared application

    NASA Astrophysics Data System (ADS)

    Jahangiri, Payam; Zarrabi, Ferdows B.; Naser-Moghadasi, Mohammad; Saee Arezoomand, Afsaneh; Heydari, Samaneh

    2017-07-01

    High Q-factor elements have been noticed for detecting biological particles with more accuracy, and in this current research, we have noticed a High Q- Factor absorber for bio sensing and as the first result we have confirmed that the higher Q- Factor is given more figure of merit in the presence of various biological materials. A parametric study has been revealed that how the dimensions effect the resonance of the absorber and the reflection. Finally, based on the manner of surface plasmon in absorbers in the interface of the metal and dielectric layer, we have developed an optical sensor by implementing a thin layer of active material. Therefore, the final structure is useful for bio sensing and energy harvesting applications. Our results revealed that the absorber particle enhanced the Absorption Cross Section for final model with an active layer of InGaAsSb and the current is increased more than 4 times in comparison with the case that we do not have any cylindrical particle.

  10. The combination of high Q factor and chirality in twin cavities and microcavity chain

    PubMed Central

    Song, Qinghai; Zhang, Nan; Zhai, Huilin; Liu, Shuai; Gu, Zhiyuan; Wang, Kaiyang; Sun, Shang; Chen, Zhiwei; Li, Meng; Xiao, Shumin

    2014-01-01

    Chirality in microcavities has recently shown its bright future in optical sensing and microsized coherent light sources. The key parameters for such applications are the high quality (Q) factor and large chirality. However, the previous reported chiral resonances are either low Q modes or require very special cavity designs. Here we demonstrate a novel, robust, and general mechanism to obtain the chirality in circular cavity. By placing a circular cavity and a spiral cavity in proximity, we show that ultra-high Q factor, large chirality, and unidirectional output can be obtained simultaneously. The highest Q factors of the non-orthogonal mode pairs are almost the same as the ones in circular cavity. And the co-propagating directions of the non-orthogonal mode pairs can be reversed by tuning the mode coupling. This new mechanism for the combination of high Q factor and large chirality is found to be very robust to cavity size, refractive index, and the shape deformation, showing very nice fabrication tolerance. And it can be further extended to microcavity chain and microcavity plane. We believe that our research will shed light on the practical applications of chirality and microcavities. PMID:25262881

  11. Enhanced Raman scattering of single nanoparticles in a high-Q whispering-gallery microresonator

    NASA Astrophysics Data System (ADS)

    Liu, Rui-Shan; Jin, Wei-Liang; Yu, Xiao-Chong; Liu, Yong-Chun; Xiao, Yun-Feng

    2015-04-01

    We study Raman scattering of single nanoparticles coupled to a high-Q whispering-gallery microresonator. It is found that cavity resonances greatly enhance the Raman signal, and the enhancement factor is as high as 108. Unlike the noncavity case, the signal power exhibits a nonmonotonic dependence on particle size, and it reaches the maximum when the Rayleigh scattering loss and the cavity intrinsic loss are comparable. We further analyze how the Raman signal intensity is influenced by different parameters including cavity quality factors and taper-cavity coupling strength. The detection limit of observing single-nanoparticle Raman signal is discussed finally. As a potential application, this mechanism may provide an alternative way to detect specific biological targets without the need of precovered biorecognitions.

  12. Maintaining high-Q in an optical microresonator coated with high-aspect-ratio gold nanorods

    NASA Astrophysics Data System (ADS)

    Ganta, D.; Dale, E. B.; Rosenberger, A. T.

    2013-10-01

    We report methods to coat fused-silica microresonators with solution-grown high-aspect-ratio (AR) gold nanorods (NRs). Microresonators coated using our method maintain an optical quality factor (Q) greater than 107 after coating. The more successful method involves silanization of the surface of the microresonator with 3-mercaptopropylmethyldimethoxysilane (MPMDMS), to enable the adhesion of gold NRs. The high-AR NR-coated microresonator combines the field enhancement of localized surface plasmon resonances with the cavity-enhanced evanescent components of high-Q whispering-gallery modes, making it useful for plasmonic sensing applications in the infrared. By coating with NRs having a different aspect ratio, the enhancement regime can be selected within a wide range of wavelengths.

  13. Label-free detection with high-Q microcavities: a review of biosensing mechanisms for integrated devices.

    PubMed

    Vollmer, Frank; Yang, Lan

    2012-12-01

    Optical microcavities that confine light in high-Q resonance promise all of the capabilities required for a successful next-generation microsystem biodetection technology. Label-free detection down to single molecules as well as operation in aqueous environments can be integrated cost-effectively on microchips, together with other photonic components, as well as electronic ones. We provide a comprehensive review of the sensing mechanisms utilized in this emerging field, their physics, engineering and material science aspects, and their application to nanoparticle analysis and biomolecular detection. We survey the most recent developments such as the use of mode splitting for self-referenced measurements, plasmonic nanoantennas for signal enhancements, the use of optical force for nanoparticle manipulation as well as the design of active devices for ultra-sensitive detection. Furthermore, we provide an outlook on the exciting capabilities of functionalized high-Q microcavities in the life sciences.

  14. Label-free detection with high-Q microcavities: a review of biosensing mechanisms for integrated devices

    PubMed Central

    Yang, Lan

    2015-01-01

    Optical microcavities that confine light in high-Q resonance promise all of the capabilities required for a successful next-generation microsystem biodetection technology. Label-free detection down to single molecules as well as operation in aqueous environments can be integrated cost-effectively on microchips, together with other photonic components, as well as electronic ones. We provide a comprehensive review of the sensing mechanisms utilized in this emerging field, their physics, engineering and material science aspects, and their application to nanoparticle analysis and biomolecular detection. We survey the most recent developments such as the use of mode splitting for self-referenced measurements, plasmonic nanoantennas for signal enhancements, the use of optical force for nanoparticle manipulation as well as the design of active devices for ultra-sensitive detection. Furthermore, we provide an outlook on the exciting capabilities of functionalized high-Q microcavities in the life sciences. PMID:26918228

  15. Calculation of light delay for coupled microrings by FDTD technique and Padé approximation.

    PubMed

    Huang, Yong-Zhen; Yang, Yue-De

    2009-11-01

    The Padé approximation with Baker's algorithm is compared with the least-squares Prony method and the generalized pencil-of-functions (GPOF) method for calculating mode frequencies and mode Q factors for coupled optical microdisks by FDTD technique. Comparisons of intensity spectra and the corresponding mode frequencies and Q factors show that the Padé approximation can yield more stable results than the Prony and the GPOF methods, especially the intensity spectrum. The results of the Prony method and the GPOF method are greatly influenced by the selected number of resonant modes, which need to be optimized during the data processing, in addition to the length of the time response signal. Furthermore, the Padé approximation is applied to calculate light delay for embedded microring resonators from complex transmission spectra obtained by the Padé approximation from a FDTD output. The Prony and the GPOF methods cannot be applied to calculate the transmission spectra, because the transmission signal obtained by the FDTD simulation cannot be expressed as a sum of damped complex exponentials.

  16. New set of design rules for resonant refractive index sensors enabled by FFT based processing of the measurement data.

    PubMed

    Gounaridis, Lefteris; Groumas, Panos; Schreuder, Erik; Heideman, Rene; Avramopoulos, Hercules; Kouloumentas, Christos

    2016-04-04

    It is still a common belief that ultra-high quality-factors (Q-factors) are a prerequisite in optical resonant cavities for high refractive index resolution and low detection limit in biosensing applications. In combination with the ultra-short steps that are necessary when the measurement of the resonance shift relies on the wavelength scanning of a laser source and conventional methods for data processing, the high Q-factor requirement makes these biosensors extremely impractical. In this work we analyze an alternative processing method based on the fast-Fourier transform, and show through Monte-Carlo simulations that improvement by 2-3 orders of magnitude can be achieved in the resolution and the detection limit of the system in the presence of amplitude and spectral noise. More significantly, this improvement is maximum for low Q-factors around 104 and is present also for high intra-cavity losses and large scanning steps making the designs compatible with the low-cost aspect of lab-on-a-chip technology. Using a micro-ring resonator as model cavity and a system design with low Q-factor (104), low amplitude transmission (0.85) and relatively large scanning step (0.25 pm), we show that resolution close to 0.01 pm and detection limit close to 10-7 RIU can be achieved improving the sensing performance by more than 2 orders of magnitude compared to the performance of systems relying on a simple peak search processing method. The improvement in the limit of detection is present even when the simple method is combined with ultra-high Q-factors and ultra-short scanning steps due to the trade-off between the system resolution and sensitivity. Early experimental results are in agreement with the trends of the numerical studies.

  17. High-Q whispering-gallery mode sensor in liquids

    NASA Astrophysics Data System (ADS)

    Nadeau, Jay L.; Ilchenko, Vladimir S.; Kossakovski, Dmitri; Bearman, Gregory H.; Maleki, Lute

    2002-06-01

    Optical sensing of biomolecules on microfabricated glass surfaces requires surface coatings that minimize nonspecific binding while preserving the optical properties of the sensor. Microspheres with whispering-gallery (WG) modes can achieve quality factor (Q) levels many orders of magnitude greater than those of other WG-based microsensors: greater than 1010 in air, and greater than 109 in a variety of solvents, including methanol, H2O and phosphate buffered saline (PBS). The presence of dyes that absorb in the wavelength of the WG excitation in the evanescent zone can cause this Q value to drop by almost 3 orders of magnitude. Silanization of the surface with mercapto-terminal silanes is compatible with high Q (>109), but chemical cross-linking of streptavidin reduces the Q to 105-106 due to build-up of a thick, irregular layer of protein. However, linkage of biotin to the silane terminus preserves the Q at a ~2x107 and yields a reactive surface sensitive to avidin-containing ligands in a concentration-dependent manner. Improvements in the reliability of the surface chemistry show promise for construction of an ultrasensitive biosensor.

  18. A secure WDM ring access network employing silicon micro-ring based remote node

    NASA Astrophysics Data System (ADS)

    Sung, Jiun-Yu; Chow, Chi-Wai; Yeh, Chien-Hung; Xu, Ke; Hsu, Chin-Wei; Su, Hong-Quan; Tsang, Hon-Ki

    2014-08-01

    A secure and scalable wavelength-division-multiplexing (WDM) ring-based access network is proposed and demonstrated using proof-of-concept experiments. In the remote node (RN), wavelength hopping for specific optical networking unit (ONU) is deployed by using silicon micro-ring resonators (SMR). Using silicon-based devices could be cost-effective for the cost-sensitive access network. Hence the optical physical layer security is introduced. The issues of denial of service (DOS) attacks, eavesdropping and masquerading can be made more difficult in the proposed WDM ring-based access network. Besides, the SMRs with different dropped wavelengths can be cascaded, such that the signals pass through the preceding SMRs can be dropped by a succeeding SMR. This can increase the scalability of the RN for supporting more ONUs for future upgrade. Here, error-free 10 Gb/s downlink and 1.25 Gb/s uplink transmission are demonstrated to show the feasibility of the proposed network.

  19. A highly efficient thermo-optic microring modulator assisted by graphene

    NASA Astrophysics Data System (ADS)

    Gan, Sheng; Cheng, Chuantong; Zhan, Yaohui; Huang, Beiju; Gan, Xuetao; Li, Shaojuan; Lin, Shenghuang; Li, Xiaofeng; Zhao, Jianlin; Chen, Hongda; Bao, Qiaoliang

    2015-11-01

    Graphene's remarkable electrical and optical properties afford great potential for constructing various optoelectronic devices, including modulators, photodetectors and pulse lasers. In particular, graphene-based optical modulators were demonstrated to be featured with a broadband response, small footprint, ultrafast speed and CMOS-compatibility, which may provide an alternative architecture for light-modulation in integrated photonic circuits. While on-chip graphene modulators have been studied in various structures, most of them are based on a capacitance-like configuration subjected to complicated fabrication processes and providing a low yield of working devices. Here, we experimentally demonstrate a new type of graphene modulator by employing graphene's electrical and thermal properties, which can be achieved with a simple fabrication flow. On a graphene-coated microring resonator with a small active area of 10 μm2, we have obtained an effective optical modulation via thermal energy electrically generated in a graphene layer. The resonant wavelength of the ring resonator shifts by 2.9 nm under an electrical power of 28 mW, which enables a large modulation depth of 7 dB and a broad operating wavelength range of 6.2 nm with 3 dB modulation. Due to the extremely high electrical and thermal conductivity in graphene, the graphene thermo-optical modulator operates at a very fast switching rate compared with the conventional silicon thermo-optic modulator, i.e. 10%-90% rise (90%-10% fall) time of 750 ns (800 ns). The results promise a novel architecture for massive on-chip modulation of optical interconnects compatible with CMOS technology.

  20. Fano resonances in prism-coupled multimode square micropillar resonators

    NASA Astrophysics Data System (ADS)

    Lee, Ho-Tong; Zhou, Linjie; Poon, Andrew W.

    2005-06-01

    We report Fano resonances in a multimode square glass micropillar resonator; the resonances were obtained by using angle-resolved prism coupling. Our experiments reveal characteristically asymmetric line shapes of high-Q resonances and of detuned low-Q resonances in multimode reflection spectra. The asymmetric resonance line shapes evolve for an approximately pi phase within a 0.5° range of reflection angles. We model our observed asymmetric multimode resonances by the far-field interference between a light wave that is evanescently coupled with a high-Q mode orbit and a coherent light wave that is refractively coupled with a detuned low-Q mode orbit.

  1. Conformational analysis of proteins with a dual polarisation silicon microring.

    PubMed

    Hoste, J-W; Werquin, S; Claes, T; Bienstman, P

    2014-02-10

    Optical microresonator biosensors have proven to be a valid tool to perform affinity analysis of a biological binding event. However, when these microresonators are excited with a single optical mode they can not distinguish between a thin dense layer of biomolecules or a thick sparse layer. This means the sensor is "blind" to changes in shape of bound biomolecules. We succeeded in exciting a Silicon-on-Insulator (SOI) microring with TE and TM polarisations simultaneously by using an asymmetrical directional coupler and as such were able to separately determine the thickness and the density (or refractive index) of a bound biolayer. A proof-of-concept is given by determining both parameters of deposited dielectric layers and by analysing the conformational changes of Bovine Serum Albumin (BSA) proteins due to a change in pH of the buffer.

  2. Detection of Single Nanoparticles Using the Dissipative Interaction in a High-Q Microcavity

    NASA Astrophysics Data System (ADS)

    Shen, Bo-Qiang; Yu, Xiao-Chong; Zhi, Yanyan; Wang, Li; Kim, Donghyun; Gong, Qihuang; Xiao, Yun-Feng

    2016-02-01

    Ultrasensitive optical detection of nanometer-scaled particles is highly desirable for applications in early-stage diagnosis of human diseases, environmental monitoring, and homeland security, but remains extremely difficult due to ultralow polarizabilities of small-sized, low-index particles. Optical whispering-gallery-mode microcavities, which can enhance significantly the light-matter interaction, have emerged as promising platforms for label-free detection of nanoscale objects. Different from the conventional whispering-gallery-mode sensing relying on the reactive (i.e., dispersive) interaction, here we propose and demonstrate to detect single lossy nanoparticles using the dissipative interaction in a high-Q toroidal microcavity. In the experiment, detection of single gold nanorods in an aqueous environment is realized by monitoring simultaneously the linewidth change and shift of the cavity mode. The experimental result falls within the theoretical prediction. Remarkably, the reactive and dissipative sensing methods are evaluated by setting the probe wavelength on and off the surface plasmon resonance to tune the absorption of nanorods, which demonstrates clearly the great potential of the dissipative sensing method to detect lossy nanoparticles. Future applications could also combine the dissipative and reactive sensing methods, which may provide better characterizations of nanoparticles.

  3. Determination of thickness and density of a wet multilayer polymer system with sub-nanometer resolution by means of a dual polarization silicon-on-insulator microring

    NASA Astrophysics Data System (ADS)

    Hoste, J.-W.; De Geest, Bruno G.; Bienstman, Peter

    2015-03-01

    Determination of both thickness and refractive index of a thin biomolecular or polymer layer in wet conditions is a task not easily performed. Available tools such as XPS, AFM, ellipsometry and integrated photonic sensors often have difficulties with the native wet condition of said agents-under-test, perform poorly in the sub-5 nm regime or do not determine both characteristics in an absolute simultaneous way. The thickness of a multilayer system is often determined by averaging over a large amount of layers, obscuring details of the individual layers. Even more, the interesting behavior of the first bound layers can be covered in noise or assumptions might be made on either thickness or refractive index in order to determine the other. To demonstrate a solution to these problems, a silicon-on-insulator (SOI) microring is used to study the adsorption of a bilayer polymer system on the silicon surface of the ring. To achieve this, the microring is simultaneously excited with TE and TM polarized light and by tracking the shifts of both resonant wavelengths, the refractive index and the thickness of the adsorbed layer can be determined with a resolution on thickness smaller than 0.1 nm and a resolution on refractive index smaller than 0.01 RIU. An adhesive polyethyleneimine (PEI) layer is adsorbed to the surface, followed by the adsorption of poly(sodium-4-styrene sulfonate) (PSS) and poly(allylamine) hydrochloride (PAH). This high-resolution performance in wet conditions with the added benefits of the SOI microring platform such as low cost and multiplexibility make for a powerful tool to analyze thin layer systems, which is promising to research binding conformation of proteins as well.

  4. Photonic crystal nanocavities fabricated from chalcogenide glass fully embedded in an index-matched cladding with a high Q-factor (>750,000).

    PubMed

    Gai, Xin; Luther-Davies, Barry; White, Thomas P

    2012-07-02

    We have designed and fabricated a 2-D photonic crystal hetero-structure cavity in the chalcogenide glass Ge(11.5)As(24)Se(64.5) that is fully embedded in a cladding with refractive index of 1.44. The low index contrast of this structure (≈1.21) means that high-Q resonances cannot be obtained using standard hetero-structure cavity designs based on W1 waveguides. We show that reducing the waveguide width can substantially improve light confinement, leading to high-Q resonances in a hetero-structure cavity. Numerical simulations indicate intrinsic Q(v) > 10(7) are possible with this approach. Experimentally, an optical cavity with a high intrinsic Q(v)>7.6 x 10(5) was achieved in a structure with a theoretical Q(v) = 1.7 x 10(6).

  5. Reconfigurable Optical Elements Based on Single and Coupled Microdisk Resonators with Quantum DOT Active Media

    DTIC Science & Technology

    2012-06-29

    thinned using a thinner to obtain one micron thick films. The dye doped films were later patterned using either EBL or photolithography. Scanning...established for the microdisk resonators. Scanning electron microscope images of single and coupled microring resonators fabricated using EBL are shown

  6. High-Q superconducting niobium cavities for gravitational wave detectors

    NASA Astrophysics Data System (ADS)

    de Paula, L. A. N.; Furtado, S. R.; Aguiar, O. D.; Oliveira, N. F., Jr.; Castro, P. J.; Barroso, J. J.

    2014-10-01

    The main purpose of this work is to optimize the electric Q-factor of superconducting niobium klystron cavities to be used in parametric transducers of the Mario Schenberg gravitational wave detector. Many cavities were manufactured from niobium with relatively high tantalum impurities (1420 ppm) and they were cryogenically tested to determine their resonance frequencies, unloaded electrical quality factors (Q0) and electromagnetic couplings. These cavities were closed with a flat niobium plate with tantalum impurities below 1000 ppm and an unloaded electrical quality factors of the order of 105 have been obtained. AC conductivity of the order of 1012 S/m has been found for niobium cavities when matching experimental results with computational simulations. These values for the Q-factor would allow the detector to reach the quantum limit of sensitivity of ~ 10-22 Hz-1/2 in the near future, making it possible to search for gravitational waves around 3.2 kHz. The experimental tests were performed at the laboratories of the National Institute for Space Research (INPE) and at the Institute for Advanced Studies (IEAv - CTA).

  7. MEMS scanning laser projection based on high-Q vacuum packaged 2D-resonators

    NASA Astrophysics Data System (ADS)

    Hofmann, U.; Eisermann, C.; Quenzer, H.-J.; Janes, J.; Schroeder, C.; Schwarzelbach, O.; Jensen, B.; Ratzmann, L.; Giese, T.; Senger, F.; Hagge, J.; Weiss, M.; Wagner, B.; Benecke, W.

    2011-03-01

    Small size, low power consumption and the capability to produce sharp images without need of an objective make MEMS scanning laser based pico-projectors an attractive solution for embedded cell-phone projection displays. To fulfil the high image resolution demands the MEMS scanning mirror has to show large scan angles, a large mirror aperture size and a high scan frequency. An additional important requirement in pico-projector applications is to minimize power consumption of the MEMS scanner to enable a long video projection time. Typically high losses in power are caused by gas damping. For that reason Fraunhofer ISIT has established a fabrication process for 2D-MEMS mirrors that includes vacuum encapsulation on 8-inch wafers. Quality factors as high as 145,000 require dedicated closed loop phase control electronics to enable stable image projection even at rapidly changing laser intensities. A capacitive feedback signal is the basis for controlling the 2D MEMS oscillation and for synchronising the laser sources. This paper reports on fabrication of two-axis wafer level vacuum packaged scanning micromirrors and its use in a compact laser projection display. The paper presents different approaches of overcoming the well-known reflex problem of packaged MEMS scanning mirrors.

  8. Raman lasing in As₂S₃ high-Q whispering gallery mode resonators.

    PubMed

    Vanier, Francis; Rochette, Martin; Godbout, Nicolas; Peter, Yves-Alain

    2013-12-01

    We report the first observation of a nonlinear process in a chalcogenide microresonator. Raman scattering and stimulated Raman scattering leading to laser oscillation is observed in microspheres made of As₂S₃. The coupled pump power threshold is as low as 13 μW using a pump wavelength of 1550 nm. The quality factor of the chalcogenide microresonator is also the highest ever reported with Q>7×10(7).

  9. High precision measurement of intensity peak shifts in tunable cascaded microring intensity sensors.

    PubMed

    Prasad, Prashanth R; Selvaraja, Shankar K; Varma, Manoj M

    2016-07-15

    We demonstrate a method to precisely track intensity peak shifts in tunable cascaded double-microring based refractive index sensors. Without modifications, width of the intensity peak of a tunable cascaded microring device limits the precision of peak-shift measurements and thereby the limit of detection of the sensor. We overcome this limitation by using dual harmonic lock-in detection for precisely determining the position of the intensity maximum. Using this modification, we have demonstrated a reduction in the full width at half-maximum (FWHM) of the intensity peak by a factor of over 1300. We show that such a reduction in FWHM of the peak curve can significantly improve the detection limit of a tunable cascaded microring-based sensor.

  10. Fiber-Optic Refractometer Based on an Etched High-Q π-Phase-Shifted Fiber-Bragg-Grating

    PubMed Central

    Zhang, Qi; Ianno, Natale J.; Han, Ming

    2013-01-01

    We present a compact and highly-sensitive fiber-optic refractometer based on a high-Q π-phase-shifted fiber-Bragg-grating (πFBG) that is chemically etched to the core of the fiber. Due to the π phase-shift, a strong πFBG forms a high-Q optical resonator and the reflection spectrum features an extremely narrow notch that can be used for highly sensitivity refractive index measurement. The etched πFBG demonstrated here has a diameter of ∼9.3 μm and a length of only 7 mm, leading to a refractive index responsivity of 2.9 nm/RIU (RIU: refractive index unit) at an ambient refractive index of 1.318. The reflection spectrum of the etched πFBG features an extremely narrow notch with a linewidth of only 2.1 pm in water centered at ∼1,550 nm, corresponding to a Q-factor of 7.4 × 105, which allows for potentially significantly improved sensitivity over refractometers based on regular fiber Bragg gratings. PMID:23845932

  11. Optimization of high-Q coupled nanobeam cavity for label-free sensing.

    PubMed

    Yaseen, Mohammad Tariq; Yang, Yi-Chun; Shih, Min-Hsiung; Chang, Yia-Chung

    2015-10-13

    We numerically and experimentally investigated the lateral coupling between photonic crystal (PhC) nanobeam (NB) cavities, pursuing high sensitivity and figure of merit (FOM) label-free biosensor. We numerically carried out 3D finite-difference time-domain (3D-FDTD) and the finite element method (FEM) simulations. We showed that when two PhC NB cavities separated by a small gap are evanescently coupled, the variation in the gap width significantly changes the coupling efficiency between the two coupled NB cavities and the resulting resonant frequencies split. Experimentally, we fabricated laterally-coupled PhC NB cavities using (InGaAsP) layer on the InP substrate. For sensing, we showed that the laterally coupled PhC NB cavities sensor exhibits higher sensitivity than the single PhC NB cavity. The higher sensitivity of laterally coupled PhC NB cavities is due to the strong evanescent coupling between nearby PhC NB cavities, which depends on the gap width and it is attributed to the large confinement of the electromagnetic field in the gap (air or liquid). As a result of the lateral coupling, both even (symmetric) and odd (asymmetric) modes exist. We show that even modes are more sensitive than odd modes. In addition, higher-order modes exhibit higher sensitivity. Hence, we characterized and examined the fabricated PhC NB cavity as a label-free biosensor, and it exhibits high figure of merit due to its high Q-factor. This illustrates a potentially useful method for optical sensing at nanoscale.

  12. Optimization of High-Q Coupled Nanobeam Cavity for Label-Free Sensing

    PubMed Central

    Yaseen, Mohammad Tariq; Yang, Yi-Chun; Shih, Min-Hsiung; Chang, Yia-Chung

    2015-01-01

    We numerically and experimentally investigated the lateral coupling between photonic crystal (PhC) nanobeam (NB) cavities, pursuing high sensitivity and figure of merit (FOM) label-free biosensor. We numerically carried out 3D finite-difference time-domain (3D-FDTD) and the finite element method (FEM) simulations. We showed that when two PhC NB cavities separated by a small gap are evanescently coupled, the variation in the gap width significantly changes the coupling efficiency between the two coupled NB cavities and the resulting resonant frequencies split. Experimentally, we fabricated laterally-coupled PhC NB cavities using (InGaAsP) layer on the InP substrate. For sensing, we showed that the laterally coupled PhC NB cavities sensor exhibits higher sensitivity than the single PhC NB cavity. The higher sensitivity of laterally coupled PhC NB cavities is due to the strong evanescent coupling between nearby PhC NB cavities, which depends on the gap width and it is attributed to the large confinement of the electromagnetic field in the gap (air or liquid). As a result of the lateral coupling, both even (symmetric) and odd (asymmetric) modes exist. We show that even modes are more sensitive than odd modes. In addition, higher-order modes exhibit higher sensitivity. Hence, we characterized and examined the fabricated PhC NB cavity as a label-free biosensor, and it exhibits high figure of merit due to its high Q-factor. This illustrates a potentially useful method for optical sensing at nanoscale. PMID:26473870

  13. Experimental study of a multipactor discharge on a dielectrics surface in a high-Q microwave cavity

    SciTech Connect

    Ivanov, O. A.; Lobaev, M. A.; Isaev, V. A.; Vikharev, A. L.

    2010-04-15

    Results from experimental studies of multipactor discharges on the surfaces of various dielectrics placed in a high-Q cylindrical microwave cavity excited at the TE{sub 013} mode in the X-band are presented. The thresholds for the onset and maintenance of a multipactor discharge on quartz, polycrystalline diamond, lithium fluoride, and Teflon surfaces possessing different roughness are determined. It is shown that, in such a resonance system, a steady multipactor discharge can operate without transition into the stage of microwave breakdown of the desorbed gas. It is found that, due to long-term action of the discharge, a thin carbon-containing film is deposited on the dielectric surface, which leads to an increase in the breakdown threshold.

  14. Purcell enhancement of fast-dephasing spontaneous emission from electron-hole droplets in high-Q silicon photonic crystal nanocavities

    NASA Astrophysics Data System (ADS)

    Sumikura, Hisashi; Kuramochi, Eiichi; Taniyama, Hideaki; Notomi, Masaya

    2016-11-01

    We have observed electron-hole droplet emission enhanced by silicon photonic crystal nanocavities with different Q values and simulated their Purcell effect using a semiclassical theory considering the temporal dephasing of the emission. When the photon loss rate of the nanocavities is smaller than the dephasing rate of the emission, the cavity-enhanced integrated photoluminescence (PL) intensity is unchanged by the cavity Q value. This is because the Purcell enhancement of the spontaneous emission rate is saturated in a high-Q region. In contrast, the peak intensity of the cavity-enhanced PL is proportional to the cavity Q value without saturation. These results suggest that a high-Q nanocavity is suitable for fabricating bright narrowband light emitting devices that concentrate the broadband emission energy of fast-dephasing emitters in a narrowband cavity resonance.

  15. An actively controlled silicon ring resonator with a fully tunable Fano resonance

    NASA Astrophysics Data System (ADS)

    Li, A.; Bogaerts, W.

    2017-09-01

    We demonstrate a novel way to generate Fano resonance with tunable wavelength, extinction ratio, and slope rate. The device is a silicon add-drop microring with two integrated tunable reflectors inside, which form an embedded Fabry-Perot cavity. The fabrication is executed at a commercial CMOS foundry. Fano resonance at the drop port is generated from the interference between the Fabry-Perot cavity mode and the ring resonance mode. By tuning the reflectivities of these two reflectors with integrated heaters, various Fano resonance shapes can be achieved with a maximum extinction ratio over 40 dB and a slope rate more than 700 dB/nm.

  16. Design and optimization of high-performance slot-microring Si-photodetector based on internal photoemission effect

    NASA Astrophysics Data System (ADS)

    Hosseinifar, Mitra; Ahmadi, Vahid; Ebnali-Heidari, Majid

    2017-08-01

    This paper presents the design and optimization of a microring resonator enhanced-internal photoemission effect-photodetectors (MRRE-IPE-PDs) suitable for optical communication. Two PD configurations are considered: the first consists of an MRR that is partially surrounded by a nanolayer of silicide with a single Schottky barrier on p-Si MRR; and the second consists of a silicide film buried in the width midpoints of a Si-based MRR where photoemission occurs over the two Schottky barriers. Several silicides are considered for the stripe (PtSi, Pd2Si, TaSi2 and CoSi2). The important features of the device, such as quantum efficiency (QE), responsivity, CW sensitivity and dark current are discussed and the trade-off between 3 dB bandwidth and QE are analyzed for nanoscaled absorption layer. In this regard, some design curves are presented for the optimized MRRE-IPE-PDs. Additionally, this paper reveals substantial improvement via comparisons with QE and responsivity measurements reported in the literature. Bandwidth-efficiency product of 61-71 GHz, responsivities of 0.8-0.9 and QE of 64-71% and the minimum receiver sensitivity of -65 to -66 dBm are also predicted for single and double Schottky barriers, respectively.

  17. Micro-Ring Structures Stabilize Microdroplets to Enable Long Term Spheroid Culture in 384 Hanging Drop Array Plates

    PubMed Central

    Hsiao, Amy Y.; Tung, Yi-Chung; Kuo, Chuan-Hsien; Mosadegh, Bobak; Bedenis, Rachel; Pienta, Kenneth J.; Takayama, Shuichi

    2012-01-01

    Using stereolithography, 20 different structural variations comprised of millimeter diameter holes surrounded by trenches, plateaus, or micro-ring structures were prepared and tested for their ability to stably hold arrays of microliter sized droplets within the structures over an extended period of time. The micro-ring structures were the most effective in stabilizing droplets against mechanical and chemical perturbations. After confirming the importance of micro-ring structures using rapid prototyping, we developed an injection molding tool for mass production of polystyrene 3D cell culture plates with an array of 384 such micro-ring surrounded through-hole structures. These newly designed and injection molded polystyrene 384 hanging drop array plates with micro-rings were stable and robust against mechanical perturbations as well as surface fouling-facilitated droplet spreading making them capable of long term cell spheroid culture of up to 22 days within the droplet array. This is a significant improvement over previously reported 384 hanging drop array plates which are susceptible to small mechanical shocks and could not reliably maintain hanging drops for longer than a few days. With enhanced droplet stability, the hanging drop array plates with micro-ring structures provide better platforms and open up new opportunities for high-throughput preparation of microscale 3D cell constructs for drug screening and cell analysis. PMID:22057945

  18. Fabrication of a free-standing Pt micro-ring on an electrode chip as a small magnetic source

    NASA Astrophysics Data System (ADS)

    Tohmyoh, Hironori; Takeda, Hironao; Saka, Masumi

    2009-08-01

    This paper describes a technique for fabricating a free-standing micro-ring on an electrode chip using a cutting and welding technique which utilizes Joule heating. A thin Pt wire with a diameter of about 650 nm was prepared on a Cu electrode chip, and mechanical deformation of the thin wire was induced by twisting it around an Ag core using a nano-manipulator. One end of the thin Pt wire was then welded by Joule heating onto another Pt wire that was located on the same electrode chip, but the Pt wire was electrically isolated from the thin Pt wire. The diameters of the micro-rings fabricated were 11 and 30 µm. The micro-ring supported by simple beams was then positioned above a permanent magnet, and the ring structure was deflected vertically by supplying a current to the ring. It was found from the experimental results that the deflection of the simply supported micro-ring was proportional to the amount of current that was supplied. The linear behavior of the deflection of the ring structure can be explained by the electromagnetic force between a micro-ring and a magnet which is proportional to the current supplied to the micro-ring.

  19. Micro - ring resonator with variety of gap width for acid rain sensing application: preliminary study

    NASA Astrophysics Data System (ADS)

    Mulyanti, B.; Ramza, H.; Pawinanto, R. E.; Rahman, J. A.; Ab-Rahman, M. S.; Putro, W. S.; Hasanah, L.; Pantjawati, A. B.

    2017-05-01

    The acid rain is an environmental disaster that it will be intimidates human life. The development micro-ring resonator sensor created from SOI (Silicon on insulator) and it used to detect acid rain index. In this study, the LUMERICAL software was used to simulate SOI material micro-ring resonator. The result shows the optimum values of fixed parameters from ring resonator have dependent variable in gap width. The layers under ring resonator with silicone (Si) and wafer layer of silicone material (Si) were added to seen three conditions of capability model. Model - 3 is an additional of bottom layer that gives the significant effect on the factor of quality. The optimum value is a peak value that given by the FSR calculation. FSR = 0, it means that is not shows the light propagation in the ring resonator and none of the light coming out on the bus - line.

  20. Design and Characterization of Multiple Coupled Microring Based Wavelength Demultiplexer in Silicon-On (soi)

    NASA Astrophysics Data System (ADS)

    Haroon, Hazura; Shaari, Sahbudin; Menon, P. S.; Mardiana, B.; Hanim, A. R.; Arsad, N.; Majlis, B. Y.; Mukhtar, W. M.; Abdullah, Huda

    We report in this paper, an optimized design and characterization of SOI based single mode, four channels wavelength demultiplexer using microrings. The usage of silicon-on-insulator (SOI) allows a wide free spectral range (FSR) for the device that is crucial in developing ultra-compact integrations of planar lightwave circuits (PLCs). The characterizations are done using Finite-Difference Time-Domain (FDTD) mode simulations from RSOFT. Serially cascaded microring arrays up to the third order are presented to study the design trade-off among the FSR, Q-factor and optical losses of the laterally coupled wavelength demultiplexer. The demultiplexer is expected to be working at C-band region of Wavelength Division Multilplexing (WDM) for a wavelength around 1550 nm. Our proposed demultiplexer has low insertion loss (< 0.5 dB) and a crosstalk around 12 ~ 19 dB.

  1. Fabrication of porous microrings via laser printing and ion-beam post-etching

    NASA Astrophysics Data System (ADS)

    Syubaev, S.; Nepomnyashchiy, A.; Mitsai, E.; Pustovalov, E.; Vitrik, O.; Kudryashov, S.; Kuchmizhak, A.

    2017-08-01

    Pulsed-laser dry printing of noble-metal microrings with a tunable internal porous structure, which can be revealed via an ion-beam etching post-procedure, was demonstrated. The abundance and average size of the pores inside the microrings were shown to be tuned in a wide range by varying the incident pulse energy and a nitrogen doping level controlled in the process of magnetron deposition of the gold film in the appropriate gaseous environment. The fabricated porous microrings were shown to provide many-fold near-field enhancement of incident electromagnetic fields, which was confirmed by mapping of the characteristic Raman band of a nanometer-thick covering layer of Rhodamine 6G dye molecules and supporting finite-difference time-domain calculations. The proposed laser-printing/ion-beam etching approach is demonstrated to be a unique tool aimed at designing and fabricating multifunctional plasmonic structures and metasurfaces for spectroscopic bioidentification based on surface-enhanced infrared absorption, Raman scattering, and photoluminescence detection schemes.

  2. High-Q band edge mode of plasmonic crystals studied by cathodoluminescence

    SciTech Connect

    Honda, Masahiro; Yamamoto, Naoki

    2014-02-24

    We have investigated the quality factor (Q-factor) of the band edge modes in the plasmonic crystal by a cathodoluminescence technique. We have found that the Q-factor at the Γ point depends on the terrace width (D)/period (P) ratio of the plasmonic crystal. The finite-difference time-domain methods predict that the band edge mode at D/P = 3/4 has a high-Q-factor (Q ∼ 250 by Palik's permittivity data and Q ∼ 530 by Johnson and Christy's data). The beam-scan spectral images allowed us to visualize the standing surface plasmon polariton waves at the band edge energies, and a high-Q-factor of ∼200 was observed at D/P ∼ 3/4.

  3. High-Q band edge mode of plasmonic crystals studied by cathodoluminescence

    NASA Astrophysics Data System (ADS)

    Honda, Masahiro; Yamamoto, Naoki

    2014-02-01

    We have investigated the quality factor (Q-factor) of the band edge modes in the plasmonic crystal by a cathodoluminescence technique. We have found that the Q-factor at the Γ point depends on the terrace width (D)/period (P) ratio of the plasmonic crystal. The finite-difference time-domain methods predict that the band edge mode at D/P = 3/4 has a high-Q-factor (Q ˜ 250 by Palik's permittivity data and Q ˜ 530 by Johnson and Christy's data). The beam-scan spectral images allowed us to visualize the standing surface plasmon polariton waves at the band edge energies, and a high-Q-factor of ˜200 was observed at D/P ˜ 3/4.

  4. High Q2 physics at HERA and searches for new particles

    NASA Astrophysics Data System (ADS)

    Matsushita, T.; Perez, E.; Rückl, R.

    1999-07-01

    Preliminary results from H1 and ZEUS on e+p scattering at high momentum transfer squared, Q2, are presented, using all available data accumulated by the H1 and ZEUS experiments between 1994-97, corresponding to integrated luminosities of 37 pb-1 and 47 pb-1, respectively. The anomalies observed at high Q2 in the 1994-96 data remain, though with less significance. Since this high Q2 domain represents a new frontier in deep inelastic scattering (DIS), these data are used to search for new particles possessing direct couplings to lepton-quark pairs. Assuming that the slight excess of events observed in neutral current DIS is due to a statistical fluctuation, preliminary limits on the production of leptoquarks and of squarks in R-parity violating the minimal supersymmetric standard model are presented.

  5. A High-Q Active Inductor Circuit for Quasi-Millimeter-Wave Frequency Range

    NASA Astrophysics Data System (ADS)

    Masuda, Toru; Hattori, Yukio; Shikama, Hiroki; Hyogo, Akira

    This paper describes a novel high-Q active inductor circuit configuration composed of an operational transconductance amplifier (OTA) and an input RC network. Due to the phase rotation made by the input RC network, the active inductor circuit provides high-Q inductive impedance at higher frequencies. According to circuit simulation with design-kit of a 90-GHz-fT SiGe HBT technology, an inductance of more than 0.53nH and Q of more than 80 can be obtained at quasi-millimeter-wave frequency, 24GHz. The Q value is tunable by controlling the transconductance of the OTA. These features are also ensured by means of measurements of fabricated active inductor circuit. Since the active inductor circuit needs small chip area, which is 25% of a conventional passive inductor, the proposed active inductor contributes to implement a cost-effective high-Q notch filter for frequencies up to quasi-millimeter-wave frequencies.

  6. Abnormal high-Q modes of coupled stadium-shaped microcavities.

    PubMed

    Ryu, Jung-Wan; Lee, Soo-Young; Kim, Inbo; Choi, Muhan; Hentschel, Martina; Kim, Sang Wook

    2014-07-15

    It is well known that the strongly deformed microcavity with fully chaotic ray dynamics cannot support high-Q modes due to its fast chaotic diffusion to the critical line of refractive emission. Here, we investigate how the Q factor is modified when two chaotic cavities are coupled, and show that some modes, whose Q factor is about 10 times higher than that of the corresponding single cavity, can exist. These abnormal high-Q modes are the result of an optimal combination of coupling and cavity geometry. As an example, in the coupled stadium-shaped microcavities, the mode pattern extends over both cavities such that it follows a whispering-gallery-type mode at both ends, whereas a big coupling spot forms at the closest contact of the two microcavities. The pattern of such a "rounded bow tie" mode allows the mode to have a high-Q factor. This mode pattern minimizes the leakage of light at both ends of the microcavities as the pattern at both ends is similar to the whispering gallery mode.

  7. Abnormal high-Q modes of coupled stadium-shaped microcavities

    NASA Astrophysics Data System (ADS)

    Ryu, Jung-Wan; Lee, Soo-Young; Kim, Inbo; Choi, Muhan; Hentschel, Martina; Kim, Sang Wook

    2014-07-01

    It is well known that the strongly deformed microcavity with fully chaotic ray dynamics cannot support high-Q modes due to its fast chaotic diffusion to the critical line of refractive emission. Here, we investigate how the Q factor is modified when two chaotic cavities are coupled, and show that some modes, whose Q factor is about 10 times higher than that of the corresponding single cavity, can exist. These abnormal high-Q modes are the result of an optimal combination of coupling and cavity geometry. As an example, in the coupled stadium-shaped microcavities, the mode pattern extends over both cavities such that it follows a whispering-gallery-type mode at both ends, whereas a big coupling spot forms at the closest contact of the two microcavities. The pattern of such a 'rounded bow tie' mode allows the mode to have a high-Q factor. This mode pattern minimizes the leakage of light at both ends of the microcavities as the pattern at both ends is similar to whispering gallery mode.

  8. Micro-resonator devices and optical broadband access application

    NASA Astrophysics Data System (ADS)

    Willner, Alan E.; Zhang, Lin; Yang, Jeng-Yuan

    2011-01-01

    Integrated photonic micro-resonators have attracted a great deal of attention in recent years, and various types of devices are demonstrated for communication and signal processing applications. In this paper, we present some of our recent work on silicon-based microring modulators, demodulators and chromatic dispersion compensators. Signal generation in on-off-keying and differential phase-shift-keying data formats is shown, while microring filters are used to carry out the demodulation of the phase-modulated signals. We also describe how to use only two ring resonators, by combining an under-coupled one with an over-coupled one, to form an on-chip single-channel dispersion compensator.

  9. Modal analysis of Bragg onion resonators

    NASA Astrophysics Data System (ADS)

    Xu, Yong; Liang, Wei; Yariv, Amnon; Fleming, James G.; Lin, Shawn-Yu

    2004-03-01

    From analysis of the high Q modes in a Bragg onion resonator with an omnidirectional reflector cladding, we establish a close analogy between such a resonator and a spherical hollow cavity in perfect metal. We demonstrate that onion resonators are ideal for applications that require a large spontaneous-emission factor ß, such as thresholdless lasers and single-photon devices.

  10. Lateral acoustic wave resonator comprising a suspended membrane of low damping resonator material

    DOEpatents

    Olsson, Roy H.; El-Kady; , Ihab F.; Ziaei-Moayyed, Maryam; Branch; , Darren W.; Su; Mehmet F.,; Reinke; Charles M.,

    2013-09-03

    A very high-Q, low insertion loss resonator can be achieved by storing many overtone cycles of a lateral acoustic wave (i.e., Lamb wave) in a lithographically defined suspended membrane comprising a low damping resonator material, such as silicon carbide. The high-Q resonator can sets up a Fabry-Perot cavity in a low-damping resonator material using high-reflectivity acoustic end mirrors, which can comprise phononic crystals. The lateral overtone acoustic wave resonator can be electrically transduced by piezoelectric couplers. The resonator Q can be increased without increasing the impedance or insertion loss by storing many cycles or wavelengths in the high-Q resonator material, with much lower damping than the piezoelectric transducer material.

  11. Advanced coupled-micro-resonator architectures for dispersion and spectral engineering applications

    NASA Astrophysics Data System (ADS)

    Van, Vien

    2009-02-01

    We report recent progress in the design and fabrication of coupled optical micro-resonators and their applications in realizing compact OEIC devices for optical spectral engineering. By leveraging synthesis techniques for analog and digital electrical circuits, advanced coupled-microring device architectures can be realized with the complexity and functionality approaching that of state-of-the-art microwave filters. In addition, the traveling wave nature of microring resonators can be exploited to realize novel devices not possible with standing wave resonators. Applications of coupledmicro- resonator devices in realizing complex optical transfer functions for amplitude, phase and group delay engineering will be presented. Progress in the practical implementation of these devices in the Silicon-on-Insulator OEIC platform will be highlighted along with the challenges and potential for constructing very high order optical filters using coupledmicroring architectures.

  12. Enhanced light extraction efficiency of micro-ring array AlGaN deep ultraviolet light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Bekele Fayisa, Gabisa; Lee, Jong Won; Kim, Jungsub; Kim, Yong-Il; Park, Youngsoo; Kim, Jong Kyu

    2017-09-01

    An effective approach to overcome inherently poor light extraction efficiency of AlGaN-based deep ultraviolet (DUV) light-emitting diodes (LEDs) is presented. We demonstrated the 5 × 5 array micro-ring DUV LED having an inclined sidewall at the outer perimeter and a p-GaN-removed inner circle of the micro-ring, together with MgF2/Al omnidirectional reflectors. The micro-ring array DUV LED shows remarkably higher light output power by 70% than the reference, consistent with the calculated result, as well as comparable turn-on and operational voltages, which are attributed to the effective extraction of strong transverse-magnetic polarized anisotropic emission and the reduction of the absorption loss by the p-GaN contact layer, simultaneously.

  13. High-Q silicon-on-insulator slot photonic crystal cavity infiltrated by a liquid

    SciTech Connect

    Caër, Charles; Le Roux, Xavier; Cassan, Eric

    2013-12-16

    We report the experimental realization of a high-Q slot photonic crystal cavity in Silicon-On-Insulator (SOI) configuration infiltrated by a liquid. Loaded Q-factor of 23 000 is measured at telecom wavelength. The intrinsic quality factor inferred from the transmission spectrum is higher than 200 000, which represents a record value for slot photonic crystal cavities on SOI, whereas the maximum of intensity of the cavity is roughly equal to 20% of the light transmitted in the waveguide. This result makes filled slot photonic crystal cavities very promising for silicon-based light emission and ultrafast nonlinear optics.

  14. On-chip spectroscopy with thermally tuned high-Q photonic crystal cavities

    SciTech Connect

    Liapis, Andreas C. Gao, Boshen; Siddiqui, Mahmudur R.; Shi, Zhimin; Boyd, Robert W.

    2016-01-11

    Spectroscopic methods are a sensitive way to determine the chemical composition of potentially hazardous materials. Here, we demonstrate that thermally tuned high-Q photonic crystal cavities can be used as a compact high-resolution on-chip spectrometer. We have used such a chip-scale spectrometer to measure the absorption spectra of both acetylene and hydrogen cyanide in the 1550 nm spectral band and show that we can discriminate between the two chemical species even though the two materials have spectral features in the same spectral region. Our results pave the way for the development of chip-size chemical sensors that can detect toxic substances.

  15. On-chip spectroscopy with thermally tuned high-Q photonic crystal cavities

    NASA Astrophysics Data System (ADS)

    Liapis, Andreas C.; Gao, Boshen; Siddiqui, Mahmudur R.; Shi, Zhimin; Boyd, Robert W.

    2016-01-01

    Spectroscopic methods are a sensitive way to determine the chemical composition of potentially hazardous materials. Here, we demonstrate that thermally tuned high-Q photonic crystal cavities can be used as a compact high-resolution on-chip spectrometer. We have used such a chip-scale spectrometer to measure the absorption spectra of both acetylene and hydrogen cyanide in the 1550 nm spectral band and show that we can discriminate between the two chemical species even though the two materials have spectral features in the same spectral region. Our results pave the way for the development of chip-size chemical sensors that can detect toxic substances.

  16. Cryogenic RF Material Testing with a High-Q Copper Cavity

    SciTech Connect

    Guo Jiquan; Tantawi, Sami; Martin, David; Yoneda, Charles

    2010-11-04

    An X-band RF cryogenic material testing system has been developed in the past few years. This system employs a high-Q copper cavity with an interchangeable flat bottom working under a TE{sub 013} like mode. By measuring the cavity Qs with a network analyzer, the system can characterize the surface resistance of different samples at different temperatures. Using a 50 MW 2{mu}s pulsed klystron, the system can measure the quenching H field for superconducting samples, up to 300-400 mT. In this paper, we will present the most recent developments of the system and testing results.

  17. Room-temperature lasing in microring cavities with an InAs/InGaAs quantum-dot active region

    SciTech Connect

    Kryzhanovskaya, N. V. Zhukov, A. E.; Nadtochy, A. M.; Maximov, M. V.; Moiseev, E. I.; Kulagina, M. M.; Savelev, A. V.; Arakcheeva, E. M.; Lipovskii, A. A.; Zubov, F. I.; Kapsalis, A.; Mesaritakis, C.; Syvridis, D.; Mintairov, A.; Livshits, D.

    2013-10-15

    Microring cavities (diameter D = 2.7-7 {mu}m) with an active region based on InAs/InGaAs quantum dots are fabricated and their characteristics are studied by the microphotoluminescence method and near-field optical microscopy. A value of 22 000 is obtained for the Q factor of a microring cavity with the diameter D = 6 {mu}m. Lasing up to room temperature is obtained in an optically pumped ring microlaser with a diameter of D = 2.7 {mu}m.

  18. Optofluidic microring flowmeter based on heat transfer effect

    NASA Astrophysics Data System (ADS)

    Gong, Yuan; Zhang, Minglei; Gong, Chaoyang; Wu, Yu; Rao, Yunjiang; Fan, Xudong

    2017-04-01

    We demonstrate an optofluidic flow rate sensor based on the heat transfer effect in a microfluidic channel for the lab-on-a-chip applications. By employing an optofluidic ring resonator (OFRR), the wavelength shift of the resonant dip of the whispering gallery mode is detected as a function of the flow rate when the flow is heated by a 1480 nm laser. A measurement range of 2 μL/min - 100 μL/min, a minimum detectable change of 30 nL/min for the flow rate detection are achieved. Experimental results indicate that the OFRR flow rate sensor has good repeatability and the inverse sensitivity is beneficial for detecting the low flow rate with high sensitivity.

  19. CMOS compatible high-Q photonic crystal nanocavity fabricated with photolithography on silicon photonic platform.

    PubMed

    Ooka, Yuta; Tetsumoto, Tomohiro; Fushimi, Akihiro; Yoshiki, Wataru; Tanabe, Takasumi

    2015-06-18

    Progress on the fabrication of ultrahigh-Q photonic-crystal nanocavities (PhC-NCs) has revealed the prospect for new applications including silicon Raman lasers that require a strong confinement of light. Among various PhC-NCs, the highest Q has been recorded with silicon. On the other hand, microcavity is one of the basic building blocks in silicon photonics. However, the fusion between PhC-NCs and silicon photonics has yet to be exploited, since PhC-NCs are usually fabricated with electron-beam lithography and require an air-bridge structure. Here we show that a 2D-PhC-NC fabricated with deep-UV photolithography on a silica-clad silicon-on-insulator (SOI) structure will exhibit a high-Q of 2.2 × 10(5) with a mode-volume of ~ 1.7(λ/n)(3). This is the highest Q demonstrated with photolithography. We also show that this device exhibits an efficient thermal diffusion and enables high-speed switching. The demonstration of the photolithographic fabrication of high-Q silica-clad PhC-NCs will open possibility for mass-manufacturing and boost the fusion between silicon photonics and CMOS devices.

  20. CMOS compatible high-Q photonic crystal nanocavity fabricated with photolithography on silicon photonic platform

    PubMed Central

    Ooka, Yuta; Tetsumoto, Tomohiro; Fushimi, Akihiro; Yoshiki, Wataru; Tanabe, Takasumi

    2015-01-01

    Progress on the fabrication of ultrahigh-Q photonic-crystal nanocavities (PhC-NCs) has revealed the prospect for new applications including silicon Raman lasers that require a strong confinement of light. Among various PhC-NCs, the highest Q has been recorded with silicon. On the other hand, microcavity is one of the basic building blocks in silicon photonics. However, the fusion between PhC-NCs and silicon photonics has yet to be exploited, since PhC-NCs are usually fabricated with electron-beam lithography and require an air-bridge structure. Here we show that a 2D-PhC-NC fabricated with deep-UV photolithography on a silica-clad silicon-on-insulator (SOI) structure will exhibit a high-Q of 2.2 × 105 with a mode-volume of ~1.7(λ/n)3. This is the highest Q demonstrated with photolithography. We also show that this device exhibits an efficient thermal diffusion and enables high-speed switching. The demonstration of the photolithographic fabrication of high-Q silica-clad PhC-NCs will open possibility for mass-manufacturing and boost the fusion between silicon photonics and CMOS devices. PMID:26086849

  1. Compact Optical Add-Drop De-Multiplexers with Cascaded Micro-Ring Resonators on SOI

    NASA Astrophysics Data System (ADS)

    Guan, Huan; Li, Zhi-Yong; Shen, Hai-Hua; Yu, Yu-De

    2017-06-01

    Not Available Supported by the National High Technology Research and Development Program of China under Grant No 2015AA016904, the National Key Research and Development Plan of China under Grant No 2016YFB0402502, and the National Natural Science Foundation of China under Grant No 61275065.

  2. Finite-element method analysis of freestanding microrings for thin-film tensile strain measurements

    NASA Astrophysics Data System (ADS)

    Boutry, M.; Bosseboeuf, A.; Grandchamp, J. P.; Coffignal, G.

    1997-12-01

    Freestanding microring structures intended for the measurement of tensile stress or strain in thin films are analysed by linear buckling FEM analysis with thermal loads. It is shown that varying the tie length is helpful for increasing the strain measurement range of narrow devices while limiting the sensitivity factor variation and the wafer surface consumption. This reduces the need for large-diameter microstructures to measure low strain values and allows strain measurements in films with different thicknesses with a lower variation of the relative accuracy.

  3. A compact cascaded microring filter with two master rings and two slave rings for sensing application

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Li, Zhi-quan; Tong, Kai

    2014-01-01

    In this paper, an ultra compact cascaded microring filter consisting of two master rings with radius of 2.5 μm and two slave rings with radius of 1 μm is presented and studied theoretically. The filter with a very large free spectral range (FSR) of 206 nm, a deep extinction ratio of 23 dB, a high quality factor of 2.76×105, and greatly suppressed spurious modes of less than 0.1 dB is achieved. The spectral responses of the filter are simulated by transfer matrix method, and the results show that this filter has a great potential of sensor application.

  4. Silicon on-chip side-coupled high-Q micro-cavities for the multiplexing of high sensitivity photonic crystal integrated sensors array

    NASA Astrophysics Data System (ADS)

    Yang, Daquan; Wang, Chunhong; Yuan, Wei; Wang, Bo; Yang, Yujie; Ji, Yuefeng

    2016-09-01

    A novel two-dimensional (2D) silicon (Si) photonic crystal (PC) α-H0-slot micro-cavity with high Q-factor and high sensitivity (S) is presented. Based on the proposed α-H0-Slot micro-cavities, an optimal design of photonic crystal integrated sensors array (PC-ISA) on monolithic silicon on insulator (SOI) is displayed. By using finite-difference time-domain (FDTD) method, the simulation results demonstrate that both large S of 200 nm/RIU (RIU=refractive index unit) and high Q-factor >104 at telecom wavelength range can be achieved simultaneously. And the sensor figure of merit (FOM)>7000 is featured, an order of magnitude improvement over previous 2D PC sensors array. In addition, for the proposed 2D PC-ISA device, each sensor unit is shown to independently shift its resonance wavelength in response to the changes in refractive index (RI) and does not perturb the others. Thus, it is potentially an ideal platform for realizing ultra-compact lab-on-a-chip applications with dense arrays of functionalized spots for multiplexed sensing, and also can be used as an opto-fluidic architecture for performing highly parallel detection of biochemical interactions in aqueous environments.

  5. Hyper-Parametric Oscillations in a Whispering Gallery Mode Fluorite Resonator

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Strekalov, Dmitry; Mohageg, Makan; Ilchenko, Vladimir; Matsko, Andrey; Maleki, Lute

    2004-01-01

    This viewgraph presentation summarizes the hyper-parametric oscillations observations of the fluorite resonator. The reporters have observed various nonlinear effects in ultra-high Q crystalline whispering gallery mode (WGM) resonators. In particular, it was demonstrated a low threshold optical hyper-parametric oscillations in a high-Q (Q=1010) CaF2 WGM resonator. The oscillations result from the resonantly enhanced four-wave-mixing occurring due to Kerr nonlinearity of the material.

  6. Nonlinear optics and crystalline whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Savchenkov, Anatoliy; Ilchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We report on our recent results concerning fabrication of high-Q whispering gallery mode crystalline resonaors, and discuss some possible applications of lithium niobate WGM resonators in nonlinear optics and photonics.

  7. Reproducibility of High-Q SRF Cavities by High Temperature Heat Treatment

    SciTech Connect

    Dhakal, Pashupati; Ciovati, Gianluigi; Kneisel, Peter; Myneni, Ganapati Rao

    2014-07-01

    Recent work on high-temperature (> 600 °C) heat treatment of ingot Nb cavities in a customized vacuum furnace for several hours showed the possibility of achieving Q0-values of up to ~5×1010 at 2.0 K, 1.5 GHz and accelerating gradients of ~20 MV/m. This contribution presents results on further studies of the heat treatment process to produce cavities with high Q0 values for continuous-wave accelerator application. Single-cell cavities of different Nb purity have been processed through few cycles of heat-treatments and chemical etching. Measurements of Q0 as a function of temperature at low RF field and of Q0 as a function of the RF field at or below 2.0 K have been made after each treatment. Measurements by TOF-SIMS of the impurities depth profiles were made on samples heat treated with the cavities.

  8. Precision Measurement of the Proton Elastic Cross Section at High Q2

    NASA Astrophysics Data System (ADS)

    Ou, Longwu; E12-07-108 Collaboration

    2017-01-01

    The measurement of proton electromagnetic form factors (FF) is a powerful way to understand the internal structure of proton and gain insight into the nature of the strong interaction. Current data of FF at high Q2 have large statistical and systematic uncertainties, which translate into large uncertainties in the extracted cross section in this kinematic range. The GMp experiment in Hall A at Jefferson Lab, starting from 2014, performed precision measurements of elastic ep scattering cross section in the Q2 range from 7 to 14 (GeV / c) 2. These measurements will improve the precision on the cross section in the covered Q2 range to about 2 % . They represent a great complement to the world's cross section data set and will be key inputs for future electromagnetic form factor experiments at similar kinematics. In this talk, the instrumentation and techniques used in the experiment will be described, and the current status of the analysis will be presented.

  9. Fabrication of high-Q microresonators in dielectric materials using a femtosecond laser: Principle and applications

    NASA Astrophysics Data System (ADS)

    Wang, Min; Lin, Jin-Tian; Xu, Ying-Xin; Fang, Zhi-Wei; Qiao, Ling-Ling; Liu, Zheng-Ming; Fang, Wei; Cheng, Ya

    2017-07-01

    Femtosecond laser micromachining has been a promising technique for fabricating three-dimensional (3D) micro/nano-structures in various kinds of dielectric materials with unprecedented spatial resolutions as well as flexibility in terms of the geometry and the materials can be processed. This unique capability opens opportunities for fabrication of 3D high-quality (Q) microresonators, which are one of the key elements in modern photonic applications. Here, we review the recent progress in fabrication of high-Q microresonators on glass and crystalline substrates by employing femtosecond laser direct writing. We demonstrate the applications of the fabricated microresonators in generating low-threshold lasers, high-sensitivity chemical sensing and nonlinear optical wavelength conversion.

  10. Intrinsically High-Q Dynamic AFM Imaging in Liquid with a Significantly Extended Needle Tip

    PubMed Central

    Minary-Jolandan, Majid; Tajik, Arash; Wang, Ning; Yu, Min-Feng

    2012-01-01

    Atomic force microscope (AFM) probe with a long and rigid needle tip was fabricated and studied for high Q factor dynamic (tapping mode) AFM imaging of samples submersed in liquid. The extended needle tip over a regular commercially-available tapping mode AFM cantilever was sufficiently long to keep the AFM cantilever from submersed in liquid, which significantly minimized the hydrodynamic damping involved in dynamic AFM imaging of samples in liquid. Dynamic AFM imaging of samples in liquid at an intrinsic Q factor of over 100 and an operation frequency of over 200 kHz was demonstrated. The method has the potential to be extended to acquire viscoelastic materials properties and provide truly gentle imaging of soft biological samples in physiological environments. PMID:22595833

  11. Harmonic mode locking in a high-Q whispering gallery mode microcavity

    NASA Astrophysics Data System (ADS)

    Tanabe, Takasumi; Kato, Takumi; Kobatake, Tomoya; Suzuki, Ryo; Chen-Jinnai, Akitoshi

    2016-03-01

    We present a numerical and experimental study of the generation of harmonic mode locking in a silica toroid microcavity. We use a generalized mean-field Lugiato-Lefever equation and solve it with the split-step Fourier method. We found that a stable harmonic mode-locking regime can be accessed when we reduce the input power after strong pumping even if we do not carefully adjust the wavelength detuning. This is due to the bistable nature of the nonlinear cavity system. The experiment agrees well with the numerical analysis, where we obtain a low-noise Kerr comb spectrum with a narrow longitudinal mode spacing by gradually reducing the input pump power after strong pumping. This finding clarifies the procedure for generating harmonic mode locking in such high-Q microcavity systems.

  12. Movable high-Q nanoresonators realized by semiconductor nanowires on a Si photonic crystal platform.

    PubMed

    Birowosuto, Muhammad Danang; Yokoo, Atsushi; Zhang, Guoqiang; Tateno, Kouta; Kuramochi, Eiichi; Taniyama, Hideaki; Takiguchi, Masato; Notomi, Masaya

    2014-03-01

    Subwavelength semiconductor nanowires have recently attracted interest for photonic applications because they possess various unique optical properties and offer great potential for miniaturizing devices. However, realizing tight light confinement or efficient coupling with photonic circuits is not straightforward and remains a challenge. Here we show that a high-Q nanocavity can be created by placing a single III–V semiconductor nanowire with a diameter of under 100 nm in a grooved waveguide in a Si photonic crystal, by means of nanoprobe manipulation. We observe very fast spontaneous emission (91 ps) from nanowires accelerated by the strong Purcell enhancement in nanocavities, which proves that very strong light confinement can be achieved. Furthermore, this system enables us to move the nanocavity anywhere along the waveguide. This configuration provides a significant degree of flexibility in integrated photonics and permits the addition and displacement of various functionalities of III–V nanocavity devices in Si photonic circuits.

  13. On-chip three-dimensional high-Q microcavities fabricated by femtosecond laser direct writing.

    PubMed

    Lin, Jintian; Yu, Shangjie; Ma, Yaoguang; Fang, Wei; He, Fei; Qiao, Lingling; Tong, Limin; Cheng, Ya; Xu, Zhizhan

    2012-04-23

    We report on the fabrication of three-dimensional (3D) high-Q whispering gallery microcavities on a fused silica chip by femtosecond laser microfabriction, enabled by the 3D nature of femtosecond laser direct writing. The processing mainly consists of formation of freestanding microdisks by femtosecond laser direct writing and subsequent wet chemical etching. CO(2) laser annealing is followed to smooth the microcavity surface. Microcavities with arbitrary tilting angle, lateral and vertical positioning are demonstrated, and the quality (Q)-factor of a typical microcavity is measured to be up to 1.07 × 10(6), which is currently limited by the low spatial resolution of the motion stage used during the laser patterning and can be improved with motion stages of higher resolutions.

  14. Vertical integration of high-Q silicon nitride microresonators into silicon-on-insulator platform.

    PubMed

    Li, Qing; Eftekhar, Ali A; Sodagar, Majid; Xia, Zhixuan; Atabaki, Amir H; Adibi, Ali

    2013-07-29

    We demonstrate a vertical integration of high-Q silicon nitride microresonators into the silicon-on-insulator platform for applications at the telecommunication wavelengths. Low-loss silicon nitride films with a thickness of 400 nm are successfully grown, enabling compact silicon nitride microresonators with ultra-high intrinsic Qs (~ 6 × 10(6) for 60 μm radius and ~ 2 × 10(7) for 240 μm radius). The coupling between the silicon nitride microresonator and the underneath silicon waveguide is based on evanescent coupling with silicon dioxide as buffer. Selective coupling to a desired radial mode of the silicon nitride microresonator is also achievable using a pulley coupling scheme. In this work, a 60-μm-radius silicon nitride microresonator has been successfully integrated into the silicon-on-insulator platform, showing a single-mode operation with an intrinsic Q of 2 × 10(6).

  15. Stabilized chip-scale Kerr frequency comb via a high-Q reference photonic microresonator

    NASA Astrophysics Data System (ADS)

    Lim, Jinkang; Huang, Shu-Wei; Vinod, Abhinav K.; Mortazavian, Parastou; Yu, Mingbin; Kwong, Dim-Lee; Savchenkov, Anatoliy A.; Matsko, Andrey B.; Maleki, Lute; Wong, Chee Wei

    2016-08-01

    We stabilize a chip-scale Si3N4 phase-locked Kerr frequency comb via locking the pump laser to an independent stable high-Q reference microresonator and locking the comb spacing to an external microwave oscillator. In this comb, the pump laser shift induces negligible impact on the comb spacing change. This scheme is a step towards miniaturization of the stabilized Kerr comb system as the microresonator reference can potentially be integrated on-chip. Fractional instability of the optical harmonics of the stabilized comb is limited by the microwave oscillator used for comb spacing lock below 1 s averaging time and coincides with the pump laser drift in the long term.

  16. Stabilized chip-scale Kerr frequency comb via a high-Q reference photonic microresonator.

    PubMed

    Lim, Jinkang; Huang, Shu-Wei; Vinod, Abhinav K; Mortazavian, Parastou; Yu, Mingbin; Kwong, Dim-Lee; Savchenkov, Anatoliy A; Matsko, Andrey B; Maleki, Lute; Wong, Chee Wei

    2016-08-15

    We stabilize a chip-scale Si3N4 phase-locked Kerr frequency comb via locking the pump laser to an independent stable high-Q reference microresonator and locking the comb spacing to an external microwave oscillator. In this comb, the pump laser shift induces negligible impact on the comb spacing change. This scheme is a step toward miniaturization of the stabilized Kerr comb system as the microresonator reference can potentially be integrated on-chip. Fractional instability of the optical harmonics of the stabilized comb is limited by the microwave oscillator used for a comb spacing lock below 1 s averaging time and coincides with the pump laser drift in the long term.

  17. Heterogeneous microring and Mach-Zehnder modulators based on lithium niobate and chalcogenide glasses on silicon

    SciTech Connect

    Rao, Ashutosh; Patil, Aniket; Chiles, Jeff; Malinowski, Marcin; Novak, Spencer; Richardson, Kathleen; Rabiei, Payam; Fathpour, Sasan

    2015-08-20

    In this study, thin films of lithium niobate are wafer bonded onto silicon substrates and rib-loaded with a chalcogenide glass, Ge23Sb7S70, to demonstrate strongly confined single-mode submicron waveguides, microring modulators, and Mach-Zehnder modulators in the telecom C band. The 200 μm radii microring modulators present 1.2 dB/cm waveguide propagation loss, 1.2 × 105 quality factor, 0.4 GHz/V tuning rate, and 13 dB extinction ratio. The 6 mm long Mach-Zehnder modulators have a half-wave voltage-length product of 3.8 V.cm and an extinction ratio of 15 dB. The demonstrated work is a key step towards enabling wafer scale dense on-chip integration of high performance lithium niobate electro-optical devices on silicon for short reach optical interconnects and higher order advanced modulation schemes.

  18. Heterogeneous microring and Mach-Zehnder modulators based on lithium niobate and chalcogenide glasses on silicon

    DOE PAGES

    Rao, Ashutosh; Patil, Aniket; Chiles, Jeff; ...

    2015-08-20

    In this study, thin films of lithium niobate are wafer bonded onto silicon substrates and rib-loaded with a chalcogenide glass, Ge23Sb7S70, to demonstrate strongly confined single-mode submicron waveguides, microring modulators, and Mach-Zehnder modulators in the telecom C band. The 200 μm radii microring modulators present 1.2 dB/cm waveguide propagation loss, 1.2 × 105 quality factor, 0.4 GHz/V tuning rate, and 13 dB extinction ratio. The 6 mm long Mach-Zehnder modulators have a half-wave voltage-length product of 3.8 V.cm and an extinction ratio of 15 dB. The demonstrated work is a key step towards enabling wafer scale dense on-chip integration ofmore » high performance lithium niobate electro-optical devices on silicon for short reach optical interconnects and higher order advanced modulation schemes.« less

  19. Study of the Exclusive d(e,e^'p)n Reaction Mechanism at High Q^2

    NASA Astrophysics Data System (ADS)

    Dashyan, Natalia; Egiyan, Kim

    2006-04-01

    High Q^2 d(e,e^'p)n scattering is one of the simplest and best ways to investigate the short range properties of the deuterium wave function (WF), possible modifications of the bound nucleon structure, as well as of the structure and nature of short range nucleon correlations (SRC). For these investigation, the mechanisms of this reaction should be understood properly. Although the d(e,e^'p)n reaction is the simplest one, its mechanism remains to be checked at high Q^2: short distances are involved and, therefore, it is unclear what degrees of freedom (nucleonic or quark-gluonic) play a more important role in electron-nucleon interaction. There are also subtle interplays between the interaction of different intermediate exited states of the struck fast nucleon with the second nucleon. To solve these problems the reaction should be investigated as completely as possible, at different kinematic conditions. We investigated the d(e,e^'p)n reaction mechanism in the Q^2 = (2 - 6) GeV^2 interval using the CLAS detector at Jefferson Lab. The angular and momentum distributions of recoil neutrons were studied in detail at momenta of pn = (0 - 2) GeV/c and in angular (relative to the transfered momentum direction) range 20^o - 160^o. The experimental data are compared with the theoretical calculations [1] based on the diagrammatic approach of , and reasonable agreement was obtained at least in the momentum range pn<= 1 GeV/c. [1]J.-M. Laget, Phys. Lett. B609, 49 (2005).

  20. On Frequency Combs in Monolithic Resonators

    NASA Astrophysics Data System (ADS)

    Savchenkov, A. A.; Matsko, A. B.; Maleki, L.

    2016-06-01

    Optical frequency combs have become indispensable in astronomical measurements, biological fingerprinting, optical metrology, and radio frequency photonic signal generation. Recently demonstrated microring resonator-based Kerr frequency combs point the way towards chip scale optical frequency comb generator retaining major properties of the lab scale devices. This technique is promising for integrated miniature radiofrequency and microwave sources, atomic clocks, optical references and femtosecond pulse generators. Here we present Kerr frequency comb development in a historical perspective emphasizing its similarities and differences with other physical phenomena. We elucidate fundamental principles and describe practical implementations of Kerr comb oscillators, highlighting associated solved and unsolved problems.

  1. Ppb-level H2S detection for SF6 decomposition based on a fiber-amplified telecommunication diode laser and a background-gas-induced high-Q photoacoustic cell

    NASA Astrophysics Data System (ADS)

    Yin, Xukun; Dong, Lei; Wu, Hongpeng; Ma, Weiguang; Zhang, Lei; Yin, Wangbao; Xiao, Liantuan; Jia, Suotang; Tittel, Frank K.

    2017-07-01

    A ppb-level hydrogen sulfide (H2S) gas sensor for sulfur hexafluoride (SF6) decomposition analysis was developed by means of a background-gas-induced high-Q differential photoacoustic cell (PAC) and a fiber-amplified telecommunication diode laser. The watt-level excitation laser power compensates the sensitivity loss as a result of using a low cost, near-IR laser source. The differential design with a large cylindrical resonator diameter allows the PAC to accommodate the high power beam and maintain a low noise level output. The theory of background-gas-induced high-Q PAC is provided and was verified experimentally. A H2S detection limit (1σ) of 109 ppb in a SF6 buffer gas was achieved for an averaging time of 1 s, which corresponds to a normalized noise equivalent absorption coefficient of 2.9 × 10-9 cm-1 W Hz-1/2.

  2. Plasmon Resonators for Quantum Computing

    DTIC Science & Technology

    2007-06-01

    quantum dot. For free atoms this strong coupling is achieved using high Q optical resonators, such as ultra-low-loss bulk Fabry - Perot cavities or...TR-07-0487 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION/AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE Unlimited UL 13. ABSTRACT (Maximum 200 words) The

  3. Coupling of semiconductor carbon nanotubes emission with silicon photonic micro ring resonators

    NASA Astrophysics Data System (ADS)

    Sarti, Francesco; Caselli, Niccolò; La China, Federico; Biccari, Francesco; Torrini, Ughetta; Intonti, Francesca; Vinattieri, Anna; Durán-Valdeiglesias, Elena; Zhang, Weiwei; Noury, Adrien; Alonso-Ramos, Carlos; Hoang, ThiHong Cam; Serna, Samuel; Le Roux, Xavier; Cassan, Eric; Izard, Nicolas; Yang, Hongliu; Bezugly, Viktor; Cuniberti, Gianaurelio; Filoramo, Arianna; Vivien, Laurent; Gurioli, Massimo

    2016-05-01

    Hybrid structures are needed to fully exploit the great advantages of Si photonics and several approaches have been addressed where Si devices are bonded to different materials and nanostructures. Here we study the use of semiconductor carbon nanotubes for emission in the 1300 nm wavelength range to functionalize Si photonic structures in view of optoelectronic applications. The Si micro-rings are fully characterized by near field forward resonant scattering with 100 nm resolution. We show that both TE and TM modes can be addressed on the top of the micro-rings in a vectorial imaging of the in-plane polarization components. We coupled the Si micro-resonators with selected carbon nanotubes for high photoluminescence emission. Coupling nanotubes with the evanescent tails in air of the electric field localized in the photonic modes of the micro-resonators is demonstrated by sharp resonances over imposed to the nanotube emission bands. By mapping the Si and the nanotube emission we demonstrate that strong enhancement of the nanotube photoluminescence can be achieved both in the photonic modes of micro-disks and slot micro-rings, whenever the spatial overlap between nano-emitters and photonic modes is fulfilled.

  4. Silicon-nanowire-based optical sensor with high sensitivity and large measurement range by using Mach-Zehnder interferometer-coupled microring

    NASA Astrophysics Data System (ADS)

    Wang, Jianwei; He, Sailing; Dai, Daoxin

    2010-12-01

    A Mach-Zehnder interferometer-coupled microring is experimentally demonstrated for optical sensing with a high sensitivity (~111 nm /RIU), a high extinction ratio (>26dB), and a very large quasi free-spectral-range (>100 nm), which helps to obtain a large measurement range. The MZI-coupled microring sensor still has good performance when the reflective index of the ambient materials largely changes (1

  5. Theoretical investigation of a polymer Mach-Zehnder electro-optic switch using 2 N + 1 serial-coupled microrings with ultralow-driving voltage

    NASA Astrophysics Data System (ADS)

    Zheng, Chuan-Tao; Luo, Qian-Qian; Huang, Xiao-Liang; Sun, Chang-Lun; Liang, Lei; Wang, Yi-Ding; Zhang, Da-Ming

    2014-09-01

    Universal structure and thorough analysis are proposed for a kind of (2 N + 1)th order polymer microring resonator Mach -Zehnder interferometer (MRR-MZI) electro-optic (EO) switch. Formulas and expressions of output power, insertion loss and crosstalk are derived, and detailed design and optimization are carried out. Analytical results indicate that, besides the first-order MRR-MZI EO switch ( N = 0), other devices for N ≥ 1 can all perform normal switching function, and 5 ≥ N ≥ 2 is preferred for dropping the crosstalk below -10 dB. For the four MRR EO switches ( N = 2-5), their switching voltages are 0.99, 0.73, 0.57 and 0.47 V, respectively; their insertion losses are within the range of 1.15-2.26 dB at bar state, whereas those are within the range of 1.95-2.42 dB at cross state; their crosstalks are within the range of 11.04-17.82 dB at bar state, whereas those are within the range of 10.34-12.51 dB at cross state. Compared with the traditional MZI EO switch, the voltage-length product (0.21 V mm) of this switching element is decreased by ~111.7 times under the same waveguide parameters. Therefore, due to small footprint size and extremely low switching voltage, this switching configuration can be densely integrated onto optoelectronic chips.

  6. Design of high Q-factor metallic nanocavities using plasmonic bandgaps.

    PubMed

    Ee, Ho-Seok; Park, Hong-Gyu; Kim, Sun-Kyung

    2016-02-10

    The surface plasmon polariton modes often excited in metallic nanocavities enable the miniaturization of photonic devices, even beyond the diffraction limit, yet their severe optical losses deteriorate device performance. This study proposes a design of metallic nanorod cavities coupled to plasmonic crystals with the aim of reducing the radiation loss of surface plasmon modes. Periodic Ag disks placed on an insulator-metal substrate open a substantial amount of plasmonic bandgaps (e.g., Δλ=290  nm at λ=1550  nm) by modifying their diameter and thickness. When an Ag nanorod with a length of ∼400  nm is surrounded by the periodic Ag disks, its Q-factor increases up to 127, yielding a 16-fold enhancement compared with a bare Ag nanorod, while its mode volume can be as small as 0.03(λ/2n)³. Ag nanorods with gradually increasing lengths exhibit high Q-factor plasmonic modes that are tunable within the plasmonic bandgap. These numerical studies on low-radiation-loss plasmonic modes excited in metallic nanocavities will promote the development of ultrasmall plasmonic devices.

  7. Development of Ultra High Gradient and High Q{sub 0} Superconducting Radio Frequency Cavities

    SciTech Connect

    Geng, Rongli; Clemens, William A.; Follkie, James E.; Harris, Teena M.; Kushnick, Peter W.; Machie, Danny; Martin, Robert E.; Palczewski, Ari D.; Perry, Era A.; Slack, Gary L.; Williams, R. S.; Adolphsen, C.; Li, Z.; Hao, J. K.; Li, Y. M.; Liu, K. X.

    2013-06-01

    We report on the recent progress at Jefferson Lab in developing ultra high gradient and high Q{sub 0} superconducting radio frequency (SRF) cavities for future SRF based machines. A new 1300 MHz 9-cell prototype cavity is being fabricated. This cavity has an optimized shape in terms of the ratio of the peak surface field (both magnetic and electric) to the acceleration gradient, hence the name low surface field (LSF) shape. The goal of the effort is to demonstrate an acceleration gradient of 50 MV/m with Q{sub 0} of 10{sup 10} at 2 K in a 9-cell SRF cavity. Fine-grain niobium material is used. Conventional forming, machining and electron beam welding method are used for cavity fabrication. New techniques are adopted to ensure repeatable, accurate and inexpensive fabrication of components and the full assembly. The completed cavity is to be first mechanically polished to a mirror-finish, a newly acquired in-house capability at JLab, followed by the proven ILC-style processing recipe established already at JLab. In parallel, new single-cell cavities made from large-grain niobium material are made to further advance the cavity treatment and processing procedures, aiming for the demonstration of an acceleration gradient of 50 MV/m with Q{sub 0} of 2-10{sup 10} at 2K.

  8. Tunability and synthetic lineshapes in high-Q optical whispering gallery modes

    NASA Technical Reports Server (NTRS)

    Ilchenko, Vladimir S.; Savchenkov, Anatoliy A.; Matsko, Andrey B.; Maleki, Lute

    2003-01-01

    We demonstrate novel techniques to manipulate spectral properties of high quality factor (Q>107) whispering-gallery modes (WGM) in optical dielectric microresonators. These include permanent frequency trimming of WGM frequencies by means of UV photosensitivity of germanium doped silica resonators electro-optical tuning of WGM in lithium niobate resonators, and cascading of microresonators for obtaining second-order filtering function. We present theoretical interpretation of experimental results, and application example of techniques for photonic microwave filtering.

  9. Low-power DAC-less PAM-4 transmitter using a cascaded microring modulator.

    PubMed

    Dubé-Demers, Raphaël; LaRochelle, Sophie; Shi, Wei

    2016-11-15

    Future super-computer interconnect systems and data centers request ultrahigh data rate links at low cost and power consumption, for which transmitters with a high level of integration and spectral efficient formats are key components. We report 60 Gb/s pulse-amplitude modulation (PAM-4) of an optical signal using a dual-microring silicon photonics circuit, making a low-power, digital-to-analog converter (DAC)-less PAM modulator. The power consumption is evaluated below 100 fJ/bit, including thermal adjustments. To the best of our knowledge, these results feature the lowest reported power consumption for PAM signaling in a DAC-less scheme for data rate beyond 40 Gb/s.

  10. Proposal for loadable and erasable optical memory unit based on dual active microring optical integrators

    NASA Astrophysics Data System (ADS)

    Ding, Yunhong; Zhang, Xiaobei; Zhang, Xinliang; Huang, Dexiu

    2008-11-01

    A novel approach for loadable and erasable optical memory unit based on dual microring optical integrators is proposed and studied. The optical integrator, which can generate an optical step function for data storing, is synthesized using active media for loss compensation and a tunable phase shifter for data reading at any time. The input data into the memory is return-to-zero (RZ) signal, and the output data read from the memory is also RZ format with a narrower pulse width. An optical digital register based on the proposed optical memory unit is also investigated and simulated, which shows the potential for large scale data storage and serial-to-parallel data conversion. A great number of such memory units can be densely integrated on a photonic circuit for future large scale data storage and buffer.

  11. Resonance patterns in a stadium-shaped microcavity

    SciTech Connect

    Lee, Soo-Young; Kurdoglyan, M.S.; Rim, Sunghwan; Kim, Chil-Min

    2004-08-01

    We investigate resonance patterns in a stadium-shaped microcavity around n{sub c}kR{approx_equal}10, where n{sub c} is the refractive index, k the vacuum wave number, and R the radius of the circular part of the cavity. We find that the patterns of high-Q resonances can be classified, even though the classical dynamics of the stadium system is chaotic. The patterns of the high-Q resonances are consistent with ray dynamical considerations and appear as stationary lasing modes with low pumping rate in a nonlinear dynamical model. All resonance patterns are presented in a finite range of kR.

  12. Perturbative QCD signatures of hybrid hadrons in electroproduction at high Q sup 2

    SciTech Connect

    Carlson, C.E. . Inst. for Nuclear Theory College of William and Mary, Williamsburg, VA . Dept. of Physics); Mukhopadhyay, N.C. . Inst. for Nuclear Theory Rensselaer Polytechnic Inst., Troy, NY . Dept. of Physics)

    1991-08-01

    In the perturbative domain of quantum chromodynamics (QCD), transverse electroproduction of hybrid baryons is small. Their longitudinal electroproduction has size and scaling behavior like normal baryons. Thus deep inelastic scattering has hybrid resonance peak to background ratio small for the transverse structure function but normal size and constant for the longitudinal one. This signature can test if the Roper resonance is a hybrid. Related high momentum transfer signatures may clarify the structure of possible non-standard states such as {Lambda}(1405), f{sub o}(975), or a{sub o}(980).

  13. Perturbative QCD signatures of hybrid hadrons in electroproduction at high Q{sup 2}

    SciTech Connect

    Carlson, C.E. |; Mukhopadhyay, N.C. |

    1991-08-01

    In the perturbative domain of quantum chromodynamics (QCD), transverse electroproduction of hybrid baryons is small. Their longitudinal electroproduction has size and scaling behavior like normal baryons. Thus deep inelastic scattering has hybrid resonance peak to background ratio small for the transverse structure function but normal size and constant for the longitudinal one. This signature can test if the Roper resonance is a hybrid. Related high momentum transfer signatures may clarify the structure of possible non-standard states such as {Lambda}(1405), f{sub o}(975), or a{sub o}(980).

  14. High- Q surface modes in photonic crystal/iron garnet film heterostructures for sensor applications

    NASA Astrophysics Data System (ADS)

    Ignatyeva, D. O.; Kapralov, P. O.; Knyazev, G. A.; Sekatskii, S. K.; Dietler, G.; Nur-E-Alam, M.; Vasiliev, M.; Alameh, K.; Belotelov, V. I.

    2016-11-01

    A novel type of a plasmonic sensor based on a magnetophotonic plasmonic heterostructure with an ultrahigh- Q resonance is considered. A magnetoplasmonic resonance with an angular width of 0.06°, which corresponds to a Q factor of 700 and is a record value for magnetoplasmonic sensors, is experimentally demonstrated. It is shown that, owing to the excitation of long-propagation-range plasmons, the transverse magneto-optical Kerr effect is considerably enhanced and, thus, the sensitivity of the magnetoplasmonic sensor to variations in the refractive index increases to 18 RIU-1, where RIU is the refractive index unit. Numerical calculations indicate that the parameters of the magnetoplasmonic structure can be further optimized to attain sensitivities up to 5 × 103 RIU-1.

  15. Electroproduction of pi0 from Delta(1232) at high Q^2 with CLAS

    NASA Astrophysics Data System (ADS)

    Ungaro, Maurizio

    2004-10-01

    We report the measurement of exclusive single π^0 electroproduction in the Δ(1232) resonance region at Jefferson Lab. The electron beam energy was 5.75 GeV, impinging on a cryogenic Hydrogen target. The CLAS spectrometer was used to detect the scattered electrons and final state protons, and the π^0's were reconstructed by the missing mass technique. π^0 angular distributions are obtained over 4 π cm solid angle for a Q^2 range 2 to 5 GeV^2/c^2. M_1+, R_em = E_1+/M_1+ and Rsm = S_1+/M_1+ multipoles for the delta resonance are extracted using the JANR unitary isobar model.

  16. Quantum logic gates based on off-resonant cavity-assisted interaction between three-level atoms and single photons

    NASA Astrophysics Data System (ADS)

    Akbari, M.; Andrianov, S. N.; Kalachev, A. A.

    2017-07-01

    A scheme for implementing quantum gates on the basis of a hybrid system that consists of flying photons and a stationary three-level atom interacting with each other in a microring resonator is developed. By employing the Schrieffer-Wolf transformation, it is shown that various two-qubit gates can be implemented under conditions of dispersive interaction without the need for orthogonal Λ structure of optical transitions. As a promising system for implementation, NV centers are considered.

  17. Superconducting Materials Testing with a High-Q Copper RF Cavity

    SciTech Connect

    Tantawi, S.G.; Dolgashev, V.; Bowden, G.; Lewandowski, J.; Nantista, C.D.; Canabal, A.; Tajima, T.; Capmpisi, I.E.; /Oak Ridge

    2007-11-07

    Superconducting RF is of increasing importance in particle accelerators. We have developed a resonant cavity with high quality factor and an interchangeable wall for testing of superconducting materials. A compact TE01 mode launcher attached to the coupling iris selectively excites the azimuthally symmetric cavity mode, which allows a gap at the detachable wall and is free of surface electric fields that could cause field emission, multipactor, and RF breakdown. The shape of the cavity is tailored to focus magnetic field on the test sample. We describe cryogenic experiments conducted with this cavity. An initial experiment with copper benchmarked our apparatus. This was followed by tests with Nb and MgB2. In addition to characterizing the onset of superconductivity with temperature, our cavity can be resonated with a high power klystron to determine the surface magnetic field level sustainable by the material in the superconducting state. A feedback code is used to make the low level RF drive track the resonant frequency.

  18. Resistive cooling circuits for charged particle traps using crystal resonators.

    PubMed

    Kaltenbacher, T; Caspers, F; Doser, M; Kellerbauer, A; Pribyl, W

    2011-11-01

    The paper addresses a novel method to couple a signal from charged particles in a Penning trap to a high Q resonant circuit using a crystal resonator. Traditionally, the trap capacity is converted into a resonator by means of an inductance. The tuned circuit's Q factor is directly linked to the input impedance "seen" by the trapped particles at resonance frequency. This parallel resonance impedance is a measure of the efficiency of resistive cooling and thus it should be optimized. We propose here a commercially available crystal resonator since it exhibits a very high Q value and a parallel resonance impedance of several MΩ. The possibility to tune the parallel resonance frequency of the quartz results in filter behavior that allows covering a range of some tens of its 3dB bandwidth by means of tuning.

  19. Compact silicon photonic resonance-assisted variable optical attenuator

    SciTech Connect

    Wang, Xiaoxi; Aguinaldo, Ryan; Lentine, Anthony; DeRose, Christopher; Starbuck, Andrew L.; Trotter, Douglas; Pomerene, Andrew; Mookherjea, Shayan

    2016-11-17

    Here, a two-part silicon photonic variable optical attenuator is demonstrated in a compact footprint which can provide a high extinction ratio at wavelengths between 1520 nm and 1620 nm. The device was made by following the conventional p-i-n waveguide section by a high-extinction-ratio second-order microring filter section. The rings provide additional on-off contrast by utilizing a thermal resonance shift, which harvested the heat dissipated by current injection in the p-i-n junction. Finally, we derive and discuss a simple thermal-resistance model in explanation of these effects.

  20. Minimizing finite-size effects in artificial resonance tunneling structures.

    PubMed

    Chak, Philip; Sipe, J E

    2006-09-01

    We consider finite-size effects in coupled cavity structures. Starting with microring resonator structures well described by transfer matrices, we obtain conditions that lead to the minimization of finite-size effects. Our approach does not require numerical optimization and requires only slight modification of design parameters guided by closed-form analytical expressions. Using a Breit-Wigner scattering formalism, we demonstrate that the scheme can be used to minimize finite-size effects in a general class of coupled cavity structures. The strength of the present technique lies in its simplicity and its applicability to a wide variety of structures described by tight-binding formalisms.

  1. Resonance-enhanced waveguide-coupled silicon-germanium detector

    NASA Astrophysics Data System (ADS)

    Alloatti, L.; Ram, R. J.

    2016-02-01

    A photodiode with 0.55 ± 0.1 A/W responsivity at a wavelength of 1176.9 nm has been fabricated in a 45 nm microelectronics silicon-on-insulator foundry process. The resonant waveguide photodetector exploits carrier generation in silicon-germanium within a microring which is compatible with high-performance electronics. A 3 dB bandwidth of 5 GHz at -4 V bias is obtained with a dark current of less than 20 pA.

  2. Compact silicon photonic resonance-assisted variable optical attenuator

    DOE PAGES

    Wang, Xiaoxi; Aguinaldo, Ryan; Lentine, Anthony; ...

    2016-11-17

    Here, a two-part silicon photonic variable optical attenuator is demonstrated in a compact footprint which can provide a high extinction ratio at wavelengths between 1520 nm and 1620 nm. The device was made by following the conventional p-i-n waveguide section by a high-extinction-ratio second-order microring filter section. The rings provide additional on-off contrast by utilizing a thermal resonance shift, which harvested the heat dissipated by current injection in the p-i-n junction. Finally, we derive and discuss a simple thermal-resistance model in explanation of these effects.

  3. Compact silicon photonic resonance-sssisted variable optical attenuator.

    PubMed

    Wang, Xiaoxi; Aguinaldo, Ryan; Lentine, Anthony; DeRose, Christopher; Starbuck, Andrew L; Trotter, Douglas; Pomerene, Andrew; Mookherjea, Shayan

    2016-11-28

    A two-part silicon photonic variable optical attenuator is demonstrated in a compact footprint which can provide a high extinction ratio at wavelengths between 1520 nm and 1620 nm. The device was made by following the conventional p-i-n waveguide section by a high-extinction-ratio second-order microring filter section. The rings provide additional on-off contrast by utilizing a thermal resonance shift, which harvested the heat dissipated by current injection in the p-i-n junction. We derive and discuss a simple thermal-resistance model in explanation of these effects.

  4. Low-voltage and compact polymeric optical switches using a Mach-Zehnder interferometer and N side-coupled electro-optic microrings

    NASA Astrophysics Data System (ADS)

    Sun, Chang-Lun; Li, Zhu-Bo; Zheng, Chuan-Tao; Luo, Qian-Qian; Huang, Xiao-Liang; Zhang, Da-Ming

    2014-11-01

    Universal structure and thorough analysis were proposed for a kind of polymer optical switch using N-th order microring resonator side-coupled Mach-Zehnder interferometer (MRR-SC-MZI). Formulation and expression of output power, insertion loss and crosstalk were derived, and detailed design and optimization were carried out. Analytical results indicate that all devices for N≥1 can perform normal switching function, and 8≥N≥2 is preferred for dropping the driving voltage below 5 V. For the seven MRR-SC-MZI EO switches (N=2-8) whose cross-state voltages are within 0-2.32 V, their bar-state voltages are within 0.96-4.83 V and their insertion losses are within 0.35-0.85 dB at bar state, whereas those within 0.14-1.70 dB at cross state; their crosstalk are within -20.79 to -31.11 dB at bar state, whereas those are within -13.86 to -20.36 dB at cross state; their 3-dB electrical bandwidths are within 18.5-28.0 GHz, and 3-dB optical bandwidths for the two output ports are within 18.1-40.0 GHz and 32.0~55 GHz, respectively. Comparison indicates that the driving voltages of the proposed MRR-SC-MZI switching devices are 10-250 times smaller than those of the traditional MZI EO switches with the same EO region length, device length and structural parameters. Therefore, due to small footprint size and low driving voltage, this switching configuration can be densely integrated onto optoelectronic chips.

  5. Selective engineering of cavity resonance for frequency matching in optical parametric processes

    SciTech Connect

    Lu, Xiyuan; Rogers, Steven; Jiang, Wei C.; Lin, Qiang

    2014-10-13

    We propose to selectively engineer a single cavity resonance to achieve frequency matching for optical parametric processes in high-Q microresonators. For this purpose, we demonstrate an approach, selective mode splitting (SMS), to precisely shift a targeted cavity resonance, while leaving other cavity modes intact. We apply SMS to achieve efficient parametric generation via four-wave mixing in high-Q silicon microresonators. The proposed approach is of great potential for broad applications in integrated nonlinear photonics.

  6. Nonlinear optics and crystalline whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey B.; Savchenkov, Anatoliy A.; Ilchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We report on our recent results concerning fabrication of high-Q whispering gallery mode (WGM) crystalline resonators, and discuss some possible applications of lithium niobate WGM resonators in nonlinear optics and photonics. In particular, we demonstrate experimentally a tunable third-order optical filter fabricated from the three metalized resonators; and report observation of parametric frequency dobuling in a WGM resonator made of periodically poled lithium niobate (PPLN).

  7. Fabrication of amorphous micro-ring arrays in crystalline silicon using ultrashort laser pulses

    NASA Astrophysics Data System (ADS)

    Fuentes-Edfuf, Yasser; Garcia-Lechuga, Mario; Puerto, Daniel; Florian, Camilo; Garcia-Leis, Adianez; Sanchez-Cortes, Santiago; Solis, Javier; Siegel, Jan

    2017-05-01

    We demonstrate a simple way to fabricate amorphous micro-rings in crystalline silicon using direct laser writing. This method is based on the fact that the phase of a thin surface layer can be changed into the amorphous phase by irradiation with a few ultrashort laser pulses (800 nm wavelength and 100 fs duration). Surface-depressed amorphous rings with a central crystalline disk can be fabricated without the need for beam shaping, featuring attractive optical, topographical, and electrical properties. The underlying formation mechanism and phase change pathway have been investigated by means of fs-resolved microscopy, identifying fluence-dependent melting and solidification dynamics of the material as the responsible mechanism. We demonstrate that the lateral dimensions of the rings can be scaled and that the rings can be stitched together, forming extended arrays of structures not limited to annular shapes. This technique and the resulting structures may find applications in a variety of fields such as optics, nanoelectronics, and mechatronics.

  8. Wave Phenomena in an Acoustic Resonant Chamber

    ERIC Educational Resources Information Center

    Smith, Mary E.; And Others

    1974-01-01

    Discusses the design and operation of a high Q acoustical resonant chamber which can be used to demonstrate wave phenomena such as three-dimensional normal modes, Q values, densities of states, changes in the speed of sound, Fourier decomposition, damped harmonic oscillations, sound-absorbing properties, and perturbation and scattering problems.…

  9. Wave Phenomena in an Acoustic Resonant Chamber

    ERIC Educational Resources Information Center

    Smith, Mary E.; And Others

    1974-01-01

    Discusses the design and operation of a high Q acoustical resonant chamber which can be used to demonstrate wave phenomena such as three-dimensional normal modes, Q values, densities of states, changes in the speed of sound, Fourier decomposition, damped harmonic oscillations, sound-absorbing properties, and perturbation and scattering problems.…

  10. High-Q silicon photonic crystal cavity for enhanced optical nonlinearities

    SciTech Connect

    Dharanipathy, Ulagalandha Perumal; Tonin, Mario; Houdré, Romuald; Minkov, Momchil Savona, Vincenzo

    2014-09-08

    We fabricate and experimentally characterize an H0 photonic crystal slab nanocavity with a design optimized for maximal quality factor, Q = 1.7 × 10{sup 6}. The cavity, fabricated from a silicon slab, has a resonant mode at λ = 1.59 μm and a measured Q-factor of 400 000. It displays nonlinear effects, including high-contrast optical bistability, at a threshold power among the lowest ever reported for a silicon device. With a theoretical modal volume as small as V = 0.34(λ/n){sup 3}, this cavity ranks among those with the highest Q/V ratios ever demonstrated, while having a small footprint suited for integration in photonic circuits.

  11. Applications and Methods of Operating a Three-dimensional Nano-electro-mechanical Resonator and Related Devices

    NASA Technical Reports Server (NTRS)

    Kaul, Anupama B. (Inventor); Epp, Larry W. (Inventor); Bagge, Leif (Inventor)

    2013-01-01

    Carbon nanofiber resonator devices, methods for use, and applications of said devices are disclosed. Carbon nanofiber resonator devices can be utilized in or as high Q resonators. Resonant frequency of these devices is a function of configuration of various conducting components within these devices. Such devices can find use, for example, in filtering and chemical detection.

  12. Ultra-low power generation of twin photons in a compact silicon ring resonator.

    PubMed

    Azzini, Stefano; Grassani, Davide; Strain, Michael J; Sorel, Marc; Helt, L G; Sipe, J E; Liscidini, Marco; Galli, Matteo; Bajoni, Daniele

    2012-10-08

    We demonstrate efficient generation of correlated photon pairs by spontaneous four wave mixing in a 5 μm radius silicon ring resonator in the telecom band around 1550 nm. By optically pumping our device with a 200 μW continuous wave laser, we obtain a pair generation rate of 0.2 MHz and demonstrate photon time correlations with a coincidence-to-accidental ratio as high as 250. The results are in good agreement with theoretical predictions and show the potential of silicon micro-ring resonators as room temperature sources for integrated quantum optics applications.

  13. Biochemical component identification by plasmonic improved whispering gallery mode optical resonance based sensor

    NASA Astrophysics Data System (ADS)

    Saetchnikov, Vladimir A.; Tcherniavskaia, Elina A.; Saetchnikov, Anton V.; Schweiger, Gustav; Ostendorf, Andreas

    2014-05-01

    Experimental data on detection and identification of variety of biochemical agents, such as proteins, microelements, antibiotic of different generation etc. in both single and multi component solutions under varied in wide range concentration analyzed on the light scattering parameters of whispering gallery mode optical resonance based sensor are represented. Multiplexing on parameters and components has been realized using developed fluidic sensor cell with fixed in adhesive layer dielectric microspheres and data processing. Biochemical component identification has been performed by developed network analysis techniques. Developed approach is demonstrated to be applicable both for single agent and for multi component biochemical analysis. Novel technique based on optical resonance on microring structures, plasmon resonance and identification tools has been developed. To improve a sensitivity of microring structures microspheres fixed by adhesive had been treated previously by gold nanoparticle solution. Another technique used thin film gold layers deposited on the substrate below adhesive. Both biomolecule and nanoparticle injections caused considerable changes of optical resonance spectra. Plasmonic gold layers under optimized thickness also improve parameters of optical resonance spectra. Biochemical component identification has been also performed by developed network analysis techniques both for single and for multi component solution. So advantages of plasmon enhancing optical microcavity resonance with multiparameter identification tools is used for development of a new platform for ultra sensitive label-free biomedical sensor.

  14. Multiple-Rayleigh-scatterer-induced mode splitting in a high-Q whispering-gallery-mode microresonator

    SciTech Connect

    Yi Xu; Xiao Yunfeng; Liu Yongchun; Li Beibei; Chen Youling; Li Yan; Gong Qihuang

    2011-02-15

    We theoretically investigate the mode-splitting phenomenon in a high-Q whispering-gallery-mode (WGM) microresonator coupled to multiple subwavelength Rayleigh scatterers. It is shown that the phase factors of the WGMs play the central role in such a system. Unlike the single-scatterer case, these phase factors in a multiscatterer system significantly influence both the modal coupling strength and the scattering-induced loss of a pair of counterpropagating WGMs. We scrutinize the condition for observing the splitting of transmission spectra. The mechanism can be used for highly sensitive biosensing, and the size of nanoparticles that can be detected is extended down to tens of nanometers.

  15. Hyperuniform photonic slabs for high-Q cavities and low-loss waveguides

    NASA Astrophysics Data System (ADS)

    Amoah, Timothy; Florescu, Marian

    2015-08-01

    Hyperuniform disordered photonic structures/solids (HUDS) are a new class of photonic solids, which display large, isotropic photonic band gaps (PBG) comparable in size to the ones found in photonic crystals (PC). The existence of large band gaps in HUDS contradicts the long-standing intuition that Bragg scattering and long- range translational order is required in PBG formation, and demonstrates that interactions between Mie-like local resonances and multiple scattering can induce on their own PBGs. HUDS combine advantages of both isotropy due to disorder (absence of long range two-point correlations) and controlled scattering properties from uniform local topology due to hyperuniformity (constrained disorder). In this paper we review the photonic properties of HUDS including the origin of PBGs and potential applications. We address technologically realisable designs of HUDS including localisation of light in point-defect-like optical cavities and the guiding of light in free-form PC waveguide analogues. We show that HUDS are a promising general-purpose design platform for integrated optical micro-circuitry, including active devices such as optical microcavity lasers and modulators.

  16. Fabrication of High-Q Nanobeam Photonic Crystals in Epitaxially Grown 4H-SiC.

    PubMed

    Bracher, David O; Hu, Evelyn L

    2015-09-09

    Silicon carbide (SiC) is an intriguing material due to the presence of spin-active point defects in several polytypes, including 4H-SiC. For many quantum information and sensing applications involving such point defects, it is important to couple their emission to high quality optical cavities. Here we present the fabrication of 1D nanobeam photonic crystal cavities (PCC) in 4H-SiC using a dopant-selective etch to undercut a homoepitaxially grown epilayer of p-type 4H-SiC. These are the first PCCs demonstrated in 4H-SiC and show high quality factors (Q) of up to ∼7000 as well as low modal volumes of <0.5 (λ/n)(3). We take advantage of the high device yield of this fabrication method to characterize hundreds of devices and determine which PCC geometries are optimal. Additionally, we demonstrate two methods to tune the resonant wavelengths of the PCCs over 5 nm without significant degradation of the Q. Lastly, we characterize nanobeam PCCs coupled to luminescence from silicon vacancy point defects (V1, V2) in 4H-SiC. The fundamental modes of two such PCCs are tuned into spectral overlap with the zero phonon line (ZPL) of the V2 center, resulting in an intensity increase of up to 3-fold. These results are important steps on the path to developing 4H-SiC as a platform for quantum information and sensing.

  17. HIGH Q0 AT MEDIUM FIELDS IN Nb3Sn SRF CAVITIES AT 4.2 K

    SciTech Connect

    Posen, Sam; Hall, Daniel Leslie; Liepe, Matthias; Proslier, T.

    2015-01-01

    Nb3Sn has proven itself to be a very promising alternative SRF material. With twice the critical temperature of niobium cavities, 1.3 GHz Nb3Sn cavities can achieve quality factors on the order of 1010 even at 4.2 K, significantly reducing cryogenic infrastructure and operational costs. In addition, its large predicted superheating field may allow for maximum accelerating gradients up to twice that of niobium for high energy applications. In this work, we report on new cavity results fromthe CornellNb3Sn SRF program demonstrating a significant improvement in the maximum field achieved with high Q0 in a Nb3Sn cavity. At 4.2 K, accelerating gradients above 16MV/m were obtainedwith Q0 of 8 × 109, showing the potential of this material for future applications. In addition to this result, current limitations are discussed.

  18. Sensing Based on Fano-Type Resonance Response of All-Dielectric Metamaterials

    PubMed Central

    Semouchkina, Elena; Duan, Ran; Semouchkin, George; Pandey, Ravindra

    2015-01-01

    A new sensing approach utilizing Mie resonances in metamaterial arrays composed of dielectric resonators is proposed. These arrays were found to exhibit specific, extremely high-Q factor (up to 15,000) resonances at frequencies corresponding to the lower edge of the array second transmission band. The observed resonances possessed with features typical for Fano resonances (FRs), which were initially revealed in atomic processes and recently detected in macro-structures, where they resulted from interference between local resonances and a continuum of background waves. Our studies demonstrate that frequencies and strength of Fano-type resonances in all-dielectric arrays are defined by interaction between local Mie resonances and Fabry-Perot oscillations of Bloch eigenmodes that makes possible controlling the resonance responses by changing array arrangements. The opportunity for obtaining high-Q responses in compact arrays is investigated and promising designs for sensing the dielectric properties of analytes in the ambient are proposed. PMID:25905701

  19. Coupling-Loss Reduction of a Vertically Coupled Microring Resonator Filter by Spot-Size-Matched Busline Waveguides

    NASA Astrophysics Data System (ADS)

    Barucci, M.; Gottardi, E.; Olivieri, E.; Pasca, E.; Risegari, L.; Ventura, G.

    2002-09-01

    We have studied the low temperature thermal properties of a polypropylene copolymer (PP): thermal conductivity (between 0.1 and 4 K), specific heat (between 0.06 and 1 K) and thermal expansion (from 4.2 K to room temperature). Both the thermal conductivity and the specific heat temperature data were interpreted using the tunnelling model for phonon scattering. The measured thermal properties show that PP is suitable for use as thermal insulating support material in cryogenic devices.

  20. Optical manipulation in optofluidic microbubble resonators

    NASA Astrophysics Data System (ADS)

    Wang, HaoTian; Wu, Xiang

    2015-11-01

    An optical manipulation system based on optofluidic microbubble resonators (MBR) is proposed. As the high- Q whispering gallery modes (WGMs) are excited in an MBR, the buildup of the field intensity inside the resonator is large enough to trap nanoscale particles. The optical gradient forces generated by the WGMs with different radial orders are investigated numerically. The negative effect of the resonance detuning induced by the particles is taken into account to investigate the optical gradient forces exerting on the particles. By the stability analysis, the WGMs with high radial orders show a better trapping stability under Brownian motion since most of the optical fields reside within the water core.

  1. Freestanding membrane composed of micro-ring array with ultrahigh sidewall aspect ratio for application in lightweight cathode arrays

    NASA Astrophysics Data System (ADS)

    Wang, Lanlan; Liu, Hongzhong; Jiang, Weitao; Gao, Wei; Chen, Bangdao; Li, Xin; Ding, Yucheng; An, Ningli

    2014-12-01

    A freestanding multilayer ultrathin nano-membrane (FUN-membrane) with a micro-ring array (MRA) is successfully fabricated through the controllable film deposition. Each micro-ring of FUN-membrane is 3 μm in diameter, 2 μm in height and sub-100 nm in sidewall thickness, demonstrating an ultrahigh sidewall aspect ratio of 20:1. In our strategy, a silica layer (200 nm in thickness), a chromium transition layer (5 nm-thick) and a gold layer (40 nm-thick), were in sequence deposited on patterned photoresist. After removal of the photoresist by lift-off process, a FUN-membrane with MRA was peeled off from the substrate, where the gold layer acted as a protecting layer to prevent the MRA from fracture. The FUN-membrane was then transferred to a flexible polycarbonate (PC) sheet coated with indium tin oxide (ITO) layer, which was then used as a flexible and lightweight cathode. Remarkably, the field emission effect of the fabricated FUN-membrane cathode performs a high field-enhancement factor of 1.2 × 104 and a low turn-on voltage of 2 V/μm, indicating the advantages of the sharp metal edge of MRA. Due to the rational design and material versatility, the FUN-membrane thus could be transferred to either rigid or flexible substrate, even curved surface, such as the skin of bio-robot's arm or leg. Additionally, the FUN-membrane composed of MRA with extremely high aspect ratio of insulator-metal sidewall, also provides potential applications in optical devices, lightweight and flexible display devices, and electronic eye imagers.

  2. Tailored Asymmetry for Enhanced Coupling to WGM Resonators

    NASA Technical Reports Server (NTRS)

    Mohageg, Makan; Maleki, Lute

    2008-01-01

    Coupling of light into and out of whispering- gallery-mode (WGM) optical resonators can be enhanced by designing and fabricating the resonators to have certain non-axisymmetric shapes (see figure). Such WGM resonators also exhibit the same ultrahigh values of the resonance quality factor (Q) as do prior WGM resonators. These WGM resonators are potentially useful as tunable narrow-band optical filters having throughput levels near unity, high-speed optical switches, and low-threshold laser resonators. These WGM resonators could also be used in experiments to investigate coupling between high-Q and chaotic modes within the resonators. For a WGM resonator made of an optically nonlinear material (e.g., lithium niobate) or another material having a high index of refraction, a prism made of a material having a higher index of refraction (e.g., diamond) must be used as part of the coupling optics. For coupling of a beam of light into (or out of) the high-Q resonator modes, the beam must be made to approach (or recede from) the resonator at a critical angle determined by the indices of refraction of the resonator and prism materials. In the case of a lithium niobate/diamond interface, this angle is approximately 22 .

  3. Public key suppression and recovery using a PANDA ring resonator for high security communication

    NASA Astrophysics Data System (ADS)

    Juleang, Pakorn; Phongsanam, Prapas; Mitatha, Somsak; Yupapin, Preecha P.

    2011-03-01

    An interesting security technique that uses the dark-bright soliton conversion control within the microring resonator is proposed. The obtained outputs for a dark-bright soliton dynamic state can be controlled and used to form the public key suppression for communication security application. However, a good design should be possible to be fabricated; therefore, by using the parameters based on the practical device parameters, the simulation results obtained have shown that the proposed system can indeed be achieved. The public key suppression and public key recovery can be used in a highly secure communication system and has potential applications in optical cryptography.

  4. Detection of the superconducting transition and magnetic flux trapping in a niobium micro-ring by using micro-Hall sensors

    NASA Astrophysics Data System (ADS)

    Kahng, Yung Ho; Kim, Yun Won; Kim, Mun Seog; Song, Woon; Choi, Jae-Hyuk; Joo, Sungjung; Hong, Jinki; Rhie, Kungwon; Lee, Soon-Gul

    2016-11-01

    An InAs heterostructure-based micro-Hall sensor was used to study the magnetic properties of a superconducting Nb micro-ring, enabling observation of magnetic phenomena such as diamagnetism onset and magnetic flux trapping in the 20- μm-diameter sample. The superconducting diamagnetism of the micro-ring was observed to develop slowly from T = 7.5 K down to 5 K and showed a notably sharp and substantial drop at 7.0 K, the zero-resistivity temperature obtained from transport measurements on a strip-patterned sample. The observed superconducting transition is discussed in terms of a percolation scenario. In magnetic-field-cooling measurements, the Hall signal from the magnetic flux trapped in the Nb ring at 4.5 K was detected at a sufficiently high level for quantitative comparison with the estimate.

  5. Proof-of-principle demonstration of Nb 3 Sn superconducting radiofrequency cavities for high Q 0 applications

    DOE PAGES

    Posen, S.; Liepe, M.; Hall, D. L.

    2015-02-23

    Many future particle accelerators require hundreds of superconducting radiofrequency (SRF) cavities operating with high duty factor. The large dynamic heat load of the cavities causes the cryogenic plant to make up a significant part of the overall cost of the facility. Our contribution can be reduced by replacing standard niobium cavities with ones coated with a low-dissipation superconductor such as Nb3Sn. Here, we present results for single cell cavities coated with Nb3Sn at Cornell. Five coatings were carried out, showing that at 4.2 K, high Q0 out to medium fields was reproducible, resulting in an average quench field of 14more » MV/m and an average 4.2 K Q0 at quench of 8 x 109 . In each case, the peak surface magnetic field at quench was well above Hc1, showing that it is not a limiting field in these cavities. Furthermore, the coating with the best performance had a quench field of 17 MV/m, exceeding gradient requirements for state-of-the-art high duty factor SRF accelerators. It is also shown that—taking into account the thermodynamic efficiency of the cryogenic plant—the 4.2 K Q0 values obtained meet the AC power consumption requirements of state-of-the-art high duty factor accelerators, making this a proof-of-principle demonstration for Nb3Sn cavities in future applications.« less

  6. Overview of high-Q2 nucleon form factor program with Super BigBite Spectrometer in JLab's Hall A

    NASA Astrophysics Data System (ADS)

    Puckett, Andrew; Jefferson Lab Hall A; Super BigBite Spectrometer Collaboration

    2017-01-01

    The elastic electromagnetic form factors (EMFFs) of the nucleon describe the impact-parameter-space distributions of electric charge and magnetization in the nucleon in the infinite momentum frame. The form factors are among the simplest and most fundamental measurable dynamical quantities describing the nucleon's structure. Precision measurements of the nucleon form factors provide stringent benchmarks testing the most sophisticated theoretical models of the nucleon, as well as ab initio calculations in lattice QCD and continuum non-perturbative QCD calculations based on the Dyson-Schwinger equations. Measurements at momentum transfers Q in the few-GeV range probe the theoretically challenging region of transition between the non-perturbative and perturbative regimes of QCD. The recent upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) to a maximum electron beam energy of 11 GeV will facilitate the measurement of the nucleon helicity-conserving (F1) and helicity-flip (F2) form factors of both proton and neutron to Q2 > 10 GeV2, In this talk, I will present an overview of the Super BigBite Spectrometer, currently under construction in CEBAF's experimental Hall A, and its physics program of high-Q2 nucleon EMFF measurements. Supported by US DOE award DE-SC0014230.

  7. Proof-of-principle demonstration of Nb$$_3$$Sn superconducting radiofrequency cavities for high $$Q_0$$ applications

    DOE PAGES

    Posen, S.; Liepe, M.; Hall, D. L.

    2015-02-01

    Many future particle accelerators require hundreds of superconducting radiofrequency (SRF) cavities operating with high duty factor. The large dynamic heat load of the cavities causes the cryogenic plant to make up a significant part of the overall cost of the facility. This contribution can be reduced by replacing standard niobium cavities with ones coated with a low-dissipation superconductor such as Nb3Sn. In this paper, we present results for single cell cavities coated with Nb3Sn at Cornell. Five coatings were carried out, showing that at 4.2 K, high Q0 out to medium fields was reproducible, resulting in an average quench fieldmore » of 14 MV/m and an average 4.2 K Q0 at quench of 8 109 . In each case, the peak surface magnetic field at quench was well above Hc1, showing that it is not a limiting field in these cavities. The coating with the best performance had a quench field of 17 MV/m, exceeding gradient requirements for state-of-the-art high duty factor SRF accelerators. It is also shown that—taking into account the thermodynamic efficiency of the cryogenic plant—the 4.2 K Q0 values obtained meet the AC power consumption requirements of state-of-the-art high duty factor accelerators, making this a proof-of-principle demonstration for Nb3Sn cavities in future applications.« less

  8. Linear and nonlinear behavior of crystalline optical whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy A.; Matsko, Andrey B.; Ilchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We demonstrate strong nonlinear behavior of high-Q whispering gallery mode (WGM) resonators made out of various crystals adn devices based on the resonators. The maximum WGM optical Q-fact or achieved at room temperature exceeds 2X10 to the tenth power.

  9. High-Q energy trapping of temperature-stable shear waves with Lamé cross-sectional polarization in a single crystal silicon waveguide

    NASA Astrophysics Data System (ADS)

    Tabrizian, R.; Daruwalla, A.; Ayazi, F.

    2016-03-01

    A multi-port electrostatically driven silicon acoustic cavity is implemented that efficiently traps the energy of a temperature-stable eigen-mode with Lamé cross-sectional polarization. Dispersive behavior of propagating and evanescent guided waves in a ⟨100⟩-aligned single crystal silicon waveguide is used to engineer the acoustic energy distribution of a specific shear eigen-mode that is well known for its low temperature sensitivity when implemented in doped single crystal silicon. Such an acoustic energy trapping in the central region of the acoustic cavity geometry and far from substrate obviates the need for narrow tethers that are conventionally used for non-destructive and high quality factor (Q) energy suspension in MEMS resonators; therefore, the acoustically engineered waveguide can simultaneously serve as in-situ self-oven by passing large uniformly distributed DC currents through its body and without any concern about perturbing the mode shape or deforming narrow supports. Such a stable thermo-structural performance besides large turnover temperatures than can be realized in Lamé eigen-modes make this device suitable for implementation of ultra-stable oven-controlled oscillators. 78 MHz prototypes implemented in arsenic-doped single crystal silicon substrates with different resistivity are transduced by in- and out-of-plane narrow-gap capacitive ports, showing high Q of ˜43k. The low resistivity device shows an overall temperature-induced frequency drift of 200 ppm over the range of -20 °C to 80 °C, which is ˜15× smaller compared to overall frequency drift measured for the similar yet high resistivity device in the same temperature range. Furthermore, a frequency tuning of ˜2100 ppm is achieved in high resistivity device by passing 45 mA DC current through its body. Continuous operation of the device under such a self-ovenizing current over 10 days did not induce frequency instability or degradation in Q.

  10. Gap-plasmon nanoantennas and bowtie resonators

    NASA Astrophysics Data System (ADS)

    Gramotnev, Dmitri K.; Pors, Anders; Willatzen, Morten; Bozhevolnyi, Sergey I.

    2012-01-01

    Plasmonic bowtie resonators involving gap surface plasmons (GSPs) in metal-insulator-metal (MIM) structures, in which only the top metal layer is structured, are investigated using numerical simulations. We demonstrate that the considered configuration features two efficiently excitable GSP resonances associated with distinct charge distributions with the domination of the dipole and quadrupole moments resulting in low- and high-Q resonances, respectively. The typical Q factors for the high-Q resonances are shown to achieve ˜25 in the near-infrared, thus potentially exceeding the quasistatic limit. Detailed physical interpretations of the obtained results and consistent dependencies of the resonance characteristics on the geometrical structural parameters are presented. Excellent resonant characteristics, the simplicity of fabrication, and tuning of the resonance wavelength by adjusting the size of the bowtie arms, separation between them, and/or thickness of the insulator (SiO2) layer in the MIM structure appear attractive for a wide variety of applications, ranging from surface sensing to photovoltaics.

  11. Bloch FDTD simulation of slow optical wave resonance cavity in optical storage technology

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Lin, Zhaohua; Cai, Lihua

    2013-08-01

    Long chain series resonance cavity is suitable for transferring slow optical wave, which can be served as the basic device for optical storage technology. Micro-ring resonator is one kind of such a long chain structure, which is considered to be the basic component of optical integrated circuit and optical computer in the future. The discrete energy level has the potential to distinguish digital optical data. The optical delay characteristics make such a device possible to store the information for some time. The advantage of this device is that it has the potential to construct an optical storage device in small geometrical dimension and could use mature semiconductor manufacture capability to lower the design and manufacturing expenses. Many experimental results have proved a lot of material and geometrical coefficients are very important for such an optical delay device. New theory method is needed to calculate the periodical energy transfer and time delay characteristics, which can be compared with experimental result. The Bloch FDTD is presented for analysis of such a new optical device, based on the optical Bloch energy band theory. The energy band characteristics of micro-ring periodical optical waveguide device is discussed used that analytical method. This precise calculated method could be served as a useful tool for design the structure of such resonance cavity to achieve desired slow optical wave transfer performance.

  12. Whispering Gallery Mode Optomechanical Resonator

    NASA Technical Reports Server (NTRS)

    Aveline, David C.; Strekalov, Dmitry V.; Yu, Nan; Yee, Karl Y.

    2012-01-01

    Great progress has been made in both micromechanical resonators and micro-optical resonators over the past decade, and a new field has recently emerged combining these mechanical and optical systems. In such optomechanical systems, the two resonators are strongly coupled with one influencing the other, and their interaction can yield detectable optical signals that are highly sensitive to the mechanical motion. A particularly high-Q optical system is the whispering gallery mode (WGM) resonator, which has many applications ranging from stable oscillators to inertial sensor devices. There is, however, limited coupling between the optical mode and the resonator s external environment. In order to overcome this limitation, a novel type of optomechanical sensor has been developed, offering great potential for measurements of displacement, acceleration, and mass sensitivity. The proposed hybrid device combines the advantages of all-solid optical WGM resonators with high-quality micro-machined cantilevers. For direct access to the WGM inside the resonator, the idea is to radially cut precise gaps into the perimeter, fabricating a mechanical resonator within the WGM. Also, a strategy to reduce losses has been developed with optimized design of the cantilever geometry and positions of gap surfaces.

  13. Resonating feathers produce courtship song.

    PubMed

    Bostwick, Kimberly S; Elias, Damian O; Mason, Andrew; Montealegre-Z, Fernando

    2010-03-22

    Male Club-winged Manakins, Machaeropterus deliciosus (Aves: Pipridae), produce a sustained tonal sound with specialized wing feathers. The fundamental frequency of the sound produced in nature is approximately 1500 Hz and is hypothesized to result from excitation of resonance in the feathers' hypertrophied shafts. We used laser Doppler vibrometry to determine the resonant properties of male Club-winged Manakin's wing feathers, as well as those of two unspecialized manakin species. The modified wing feathers exhibit a response peak near 1500 Hz, and unusually high Q-values (a measure of resonant tuning) for biological objects (Q up to 27). The unmodified wing feathers of the Club-winged Manakin do not exhibit strong resonant properties when measured in isolation. However, when measured still attached to the modified feathers (nine feathers held adjacent by an intact ligament), they resonate together as a unit near 1500 Hz, and the wing produces a second harmonic of similar or greater amplitude than the fundamental. The feathers of the control species also exhibit resonant peaks around 1500 Hz, but these are significantly weaker, the wing does not resonate as a unit and no harmonics are produced. These results lend critical support to the resonant stridulation hypothesis of sound production in M. deliciosus.

  14. High-Q ultrasonic determination of the critical nanoaggregate concentration of asphaltenes and the critical micelle concentration of standard surfactants.

    PubMed

    Andreatta, Gaëlle; Bostrom, Neil; Mullins, Oliver C

    2005-03-29

    Asphaltenes are known to be interfacially active in many circumstances such as at toluene-water interfaces. Furthermore, the term micelle has been used to describe the primary aggregation of asphaltenes in good solvents such as toluene. Nevertheless, there has been significant uncertainty regarding the critical micelle concentration (CMC) of asphaltenes and even whether the micelle concept is appropriate for asphaltenes. To avoid semantic debates we introduce the terminology critical nanoaggregate concentration (CNAC) for asphaltenes. In this report, we investigate asphaltenes and standard surfactants using high-Q, ultrasonic spectroscopy in both aqueous and organic solvents. As expected, standard surfactants are shown to exhibit a sharp break in sonic velocity versus concentration at known CMCs. To prove our methods, we measured known surfactants with CMCs in the range from 0.010 g/L to 2.3 g/L in agreement with the literature. Using density determinations, we obtain micelle compressibilities consistent with previous literature reports. Asphaltenes are also shown to exhibit behavior similar to that of ultrasonic velocity versus concentration as standard surfactants; asphaltene CNACs in toluene occur at roughly 0.1 g/L, although the exact concentration depends on the specific (crude oil) asphaltene. Furthermore, using asphaltene solution densities, we show that asphaltene nanoaggregate compressibilities are similar to micellar compressibilities obtained with standard nonionic surfactants in toluene. These results strongly support the contention that asphaltenes in toluene can be treated roughly within the micelle framework, although asphaltenes may exhibit small levels of aggregation (dimers, etc.) below their CNAC. Furthermore, our extensive results on known surfactants agree with the literature while the asphaltene CNACs reported here are one to two orders of magnitude lower than most previously published results. (Previous work utilized the terminology "micelle

  15. Frequency-temperature sensitivity reduction with optimized microwave Bragg resonators

    NASA Astrophysics Data System (ADS)

    Le Floch, J.-M.; Murphy, C.; Hartnett, J. G.; Madrangeas, V.; Krupka, J.; Cros, D.; Tobar, M. E.

    2017-01-01

    Dielectric resonators are employed to build state-of-the-art low-noise and high-stability oscillators operating at room and cryogenic temperatures. A resonator temperature coefficient of frequency is one criterion of performance. This paper reports on predictions and measurements of this temperature coefficient of frequency for three types of cylindrically symmetric Bragg resonators operated at microwave frequencies. At room temperature, microwave Bragg resonators have the best potential to reach extremely high Q-factors. Research has been conducted over the last decade on modeling, optimizing, and realizing such high Q-factor devices for applications such as filtering, sensing, and frequency metrology. We present an optimized design, which has a temperature sensitivity 2 to 4 times less than current whispering gallery mode resonators without using temperature compensating techniques and about 30% less than other existing Bragg resonators. Also, the performance of a new generation single-layered Bragg resonator, based on a hybrid-Bragg-mode, is reported with a sensitivity of about -12 ppm/K at 295 K. For a single reflector resonator, it achieves a similar level of performance as a double-Bragg-reflector resonator but with a more compact structure and performs six times better than whispering-gallery-mode resonators. The hybrid resonator promises to deliver a new generation of high-sensitivity sensors and high-stability room-temperature oscillators.

  16. Dynamic metamaterial based on the graphene split ring high-Q Fano-resonnator for sensing applications.

    PubMed

    Tang, Weiwei; Wang, Lin; Chen, Xiaoshuang; Liu, Changlong; Yu, Anqi; Lu, Wei

    2016-08-18

    Structured plasmonic metamaterials offer a new way to design functionalized optical and electrical components, since they can be size-scaled for operation across the whole electromagnetic spectrum. Here, we theoretically investigated electrical active split ring resonators based on graphene metamaterials on a SiO2/Si substrate that shows tunable frequency and amplitude modulation. For the symmetrical structure, the modulation depth of the frequency and amplitude can reach 58.58% and 99.35%, and 59.53% and 97.7% respectively in the two crossed-polarization orientations. Once asymmetry is introduced in the structure, the higher order mode which is inaccessible in the symmetrical structure can be excited, and a strong interaction among the modes in the split ring resonator forms a transparency window in the absorption band of the dipole resonance. Such metamaterials could facilitate the design of active modulation, and slow light effect for terahertz waves. Potential outcomes such as higher sensing abilities and higher-Q resonances at terahertz frequencies are demonstrated through numerical simulations with realistic parameters.

  17. Label-Free Optical Ring Resonator Bio/Chemical Sensors

    NASA Astrophysics Data System (ADS)

    Zhu, Hongying; Suter, Jonathan D.; Fan, Xudong

    Optical micro-ring resonator sensors are an emerging category of label-free optical sensors for bio/chemical sensing that have recently been under intensive investigation. Researchers of this technology have been motivated by a tremendous breadth of different applications, including medical diagnosis, environmental monitoring, homeland security, and food quality control, which require sensitive analytical tools. Ring resonator sensors use total internal reflection to support circulating optical resonances called whispering gallery modes (WGMs). The WGMs have an evanescent field of several hundred nanometers into the surrounding medium, and can therefore detect the refractive index change induced when the analyte binds to the resonator surface. Despite the small physical size of a resonator, the circulating nature of the WGM creates extremely long effective lengths, greatly increasing light-matter interaction and improving its sensing performance. Moreover, only small sample volume is needed for detection because the sensors can be fabricated in sizes well below 100 μm. The small footprint allows integration of those ring resonator sensors onto lab-on-a-chip types of devices for multiplexed detection.

  18. Torsional Resonators Based on Inorganic Nanotubes.

    PubMed

    Divon, Yiftach; Levi, Roi; Garel, Jonathan; Golberg, Dmitri; Tenne, Reshef; Ya'akobovitz, Assaf; Joselevich, Ernesto

    2017-01-11

    We study for the first time the resonant torsional behaviors of inorganic nanotubes, specifically tungsten disulfide (WS2) and boron nitride (BN) nanotubes, and compare them to that of carbon nanotubes. We have found WS2 nanotubes to have the highest quality factor (Q) and torsional resonance frequency, followed by BN nanotubes and carbon nanotubes. Dynamic and static torsional spring constants of the various nanotubes were found to be different, especially in the case of WS2, possibly due to a velocity-dependent intershell friction. These results indicate that inorganic nanotubes are promising building blocks for high-Q nanoelectromechanical systems (NEMS).

  19. Metal-capped silicon organic micro-ring electro-optical modulator (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Zaki, Aya O.; Kirah, Khaled A.; Swillam, Mohamed A.

    2017-02-01

    An ultra-compact hybrid plasmonic waveguide ring electro-optical modulator is designed to be easily fabricated on silicon on insulator (SOI) substrates using standard silicon photonics technology. The proposed waveguide is based on a buried standard silicon waveguide of height 220 nm topped with polymer and metal. The key advantage of this novel design is that only the silicon layer of the waveguide is structured as a coupled ring resonator. Then, the device is covered with electro-optical polymer and metal in post processes with no need for lithography or accurate mask alignment techniques. The simple fabrication method imposes many design challenges to obtain a resonator of reasonable loaded quality factor and high extinction ratio. Here, the performance of the resonator is optimized in the telecom wavelength range around 1550 nm using 3D FDTD simulations. The design of the coupling junction between the access waveguide and the tightly bent ring is thoroughly studied. The extension of the metal over the coupling region is exploited to make the critical dimension of the design geometry at least 2.5 times larger than conventional plasmonic resonators and the design is thus more robust. In this paper, we demonstrate an electro-optical modulator that offers an insertion loss < 1 dB, a modulation depth of 12 dB for an applied peak to peak voltage of only 2 V and energy consumption of 1.74 fJ/bit. The performance is superior to previously reported hybrid plasmonic ring resonator based modulators while the design shows robustness and low fabrication cost.

  20. High-Q X-Band and K-Band Micromachined Spiral Inductors for Use in Si-Based ICs

    NASA Technical Reports Server (NTRS)

    Lu, Liang-Hung; Bhattacharya, Pallab; Katehi, Linda P. B.; Ponchak, George E.

    2000-01-01

    A micromachined structure with reduced parasitics is proposed to enhance the resonant frequency and the quality factor (Q) of a spiral inductor. Inductors with various etch depths have been fabricated on a high resistivity Si substrate. Two-port S-parameters measurement is taken to characterize the performance of the inductors. With an etch depth of 20 micron, a fabricated 1.8 nH spiral inductor achieves a maximum resonant frequency of 25.6 GHz and a maximum Q of 20.2 at 14.5 GHz. This technology is compatible with SiGe/Si HBT technology, and the spiral inductors are especially suitable for Si-based monolithic microwave integrated circuit (MMIC) applications.

  1. Resonant optical transducers for in-situ gas detection

    SciTech Connect

    Bond, Tiziana C; Cole, Garrett; Goddard, Lynford

    2016-06-28

    Configurations for in-situ gas detection are provided, and include miniaturized photonic devices, low-optical-loss, guided-wave structures and state-selective adsorption coatings. High quality factor semiconductor resonators have been demonstrated in different configurations, such as micro-disks, micro-rings, micro-toroids, and photonic crystals with the properties of very narrow NIR transmission bands and sensitivity up to 10.sup.-9 (change in complex refractive index). The devices are therefore highly sensitive to changes in optical properties to the device parameters and can be tunable to the absorption of the chemical species of interest. Appropriate coatings applied to the device enhance state-specific molecular detection.

  2. High-Q (>750,000) photonic crystal nanocavities fabricated from chalcogenide glass fully embedded in an index-matched cladding

    NASA Astrophysics Data System (ADS)

    Gai, Xin; Luther-Davies, Barry; White, Thomas P.

    2012-06-01

    We have fabricated a Ge11.5As24Se64.5 2-D photonic crystal containing a hetero-structure cavity fully embedded in a cladding with index of 1.44. Because of the low index contrast of this structure (~1.2) we had to use a W0.54 defect waveguide to inhibit losses to continuum modes above the light line. By has allowed optical cavities with very high Q (>750,000) to be obtained.

  3. Amplitude and Transverse Quadrature Component Squeezing of Coherent Light in High Q Cavity by Injection of Atoms of Two-Photon Transition

    NASA Technical Reports Server (NTRS)

    Cao, Chang-Qi

    1996-01-01

    The amplitude and transverse quadrature component squeezing of coherent light in high Q cavity by injection of atoms of two-photon transition are studied. The Golubev-Sokolov master equation and generating function approach are utilized to derive the exact variances of photon number and of transverse quadrature component as function of t. The correlation functions and power spectrums of photon number noise and of output photon current noise are also investigated.

  4. Control of emission spectra in quantum dot microdisk/microring lasers.

    PubMed

    Kryzhanovskaya, N V; Mukhin, I S; Moiseev, E I; Shostak, I I; Bogdanov, A A; Nadtochiy, A M; Maximov, M V; Zhukov, A E; Kulagina, M M; Vashanova, K A; Zadiranov, Yu M; Troshkov, S I; Lipovskii, A A; Mintairov, A

    2014-10-20

    Focused ion beam is applied to quantum dot based microresonators to form pits or groove on their surface. The emission spectra of the resonators based lasers are significantly thinned out after the ion beam milling, and one or two modes become dominant instead of a group of modes having comparable intensities. The linewidth of the lasing mode is kept unchanged, whereas the lasing threshold demonstrates an insignificant growth.

  5. A Low-Noise CMOS THz Imager Based on Source Modulation and an In-Pixel High-Q Passive Switched-Capacitor N-Path Filter.

    PubMed

    Boukhayma, Assim; Dupret, Antoine; Rostaing, Jean-Pierre; Enz, Christian

    2016-03-03

    This paper presents the first low noise complementary metal oxide semiconductor (CMOS) deletedCMOS terahertz (THz) imager based on source modulation and in-pixel high-Q filtering. The 31 × 31 focal plane array has been fully integrated in a 0 . 13 μ m standard CMOS process. The sensitivity has been improved significantly by modulating the active THz source that lights the scene and performing on-chip high-Q filtering. Each pixel encompass a broadband bow tie antenna coupled to an N-type metal-oxide-semiconductor (NMOS) detector that shifts the THz radiation, a low noise adjustable gain amplifier and a high-Q filter centered at the modulation frequency. The filter is based on a passive switched-capacitor (SC) N-path filter combined with a continuous-time broad-band Gm-C filter. A simplified analysis that helps in designing and tuning the passive SC N-path filter is provided. The characterization of the readout chain shows that a Q factor of 100 has been achieved for the filter with a good matching between the analytical calculation and the measurement results. An input-referred noise of 0 . 2 μ V RMS has been measured. Characterization of the chip with different THz wavelengths confirms the broadband feature of the antenna and shows that this THz imager reaches a total noise equivalent power of 0 . 6 nW at 270 GHz and 0 . 8 nW at 600 GHz.

  6. The stiffness variation of a micro-ring driven by a traveling piecewise-electrode.

    PubMed

    Li, Yingjie; Yu, Tao; Hu, Yuh-Chung

    2014-09-16

    In the practice of electrostatically actuated micro devices; the electrostatic force is implemented by sequentially actuated piecewise-electrodes which result in a traveling distributed electrostatic force. However; such force was modeled as a traveling concentrated electrostatic force in literatures. This article; for the first time; presents an analytical study on the stiffness variation of microstructures driven by a traveling piecewise electrode. The analytical model is based on the theory of shallow shell and uniform electrical field. The traveling electrode not only applies electrostatic force on the circular-ring but also alters its dynamical characteristics via the negative electrostatic stiffness. It is known that; when a structure is subjected to a traveling constant force; its natural mode will be resonated as the traveling speed approaches certain critical speeds; and each natural mode refers to exactly one critical speed. However; for the case of a traveling electrostatic force; the number of critical speeds is more than that of the natural modes. This is due to the fact that the traveling electrostatic force makes the resonant frequencies of the forward and backward traveling waves of the circular-ring different. Furthermore; the resonance and stability can be independently controlled by the length of the traveling electrode; though the driving voltage and traveling speed of the electrostatic force alter the dynamics and stabilities of microstructures. This paper extends the fundamental insights into the electromechanical behavior of microstructures driven by electrostatic forces as well as the future development of MEMS/NEMS devices with electrostatic actuation and sensing.

  7. Realizing topological edge states in a silicon nitride microring-based photonic integrated circuit.

    PubMed

    Yin, Chenxuan; Chen, Yujie; Jiang, Xiaohui; Zhang, Yanfeng; Shao, Zengkai; Xu, Pengfei; Yu, Siyuan

    2016-10-15

    Topological edge states in a photonic integrated circuit based on the platform of silicon nitride are demonstrated with a two-dimensional coupled resonator optical waveguide array involving the synthetic magnetic field for photons at near-infrared wavelengths. Measurements indicate that the topological edge states can be observed at certain wavelengths, with light travelling around the boundary of the array. Combined with the induced disorders in fabrication near the edge, the system shows the defect immunity under the topological protection of edge states.

  8. Design of triply-resonant microphotonic parametric oscillators based on Kerr nonlinearity.

    PubMed

    Zeng, Xiaoge; Popović, Miloš A

    2014-06-30

    We propose optimal designs for triply-resonant optical parametric oscillators (OPOs) based on degenerate four-wave mixing (FWM) in microcavities. We show that optimal designs in general call for different external coupling to pump and signal/idler resonances. We provide a number of normalized performance metrics including threshold pump power and maximum achievable conversion efficiency for OPOs with and without two-photon (TPA) and free-carrier absorption (FCA). We find that the maximum achievable conversion efficiency is bound to an upper limit by nonlinear and free-carrier losses independent of pump power, while linear losses only increase the pump power required to achieve a certain conversion efficiency. The results of this work suggest unique advantages in on-chip implementations that allow explicit engineering of resonances, mode field overlaps, dispersion, and wavelength-and mode-selective coupling. We provide universal design curves that yield optimum designs, and give example designs of microring-resonator-based OPOs in silicon at the wavelengths 1.55 μm (with TPA) and 2.3 μm (no TPA) as well as in silicon nitride (Si(3)N(4)) at 1.55 μm. For typical microcavity quality factor of 10(6), we show that the oscillation threshold in excitation bus can be well into the sub-mW regime for silicon microrings and a few mW for silicon nitride microrings. The conversion efficiency can be a few percent when pumped at 10 times of the threshold. Next, based on our results, we suggest a family of synthetic "photonic molecule"-like, coupled-cavity systems to implement optimum FWM, where structure design for control of resonant wavelengths can be separated from that of optimizing nonlinear conversion efficiency, and where furthermore pump, signal, and idler coupling to bus waveguides can be controlled independently, using interferometric cavity supermode coupling as an example. Finally, consideration of these complex geometries calls for a generalization of the nonlinear

  9. Miniature Sapphire Acoustic Resonator - MSAR

    NASA Technical Reports Server (NTRS)

    Wang, Rabi T.; Tjoelker, Robert L.

    2011-01-01

    A room temperature sapphire acoustics resonator incorporated into an oscillator represents a possible opportunity to improve on quartz ultrastable oscillator (USO) performance, which has been a staple for NASA missions since the inception of spaceflight. Where quartz technology is very mature and shows a performance improvement of perhaps 1 dB/decade, these sapphire acoustic resonators when integrated with matured quartz electronics could achieve a frequency stability improvement of 10 dB or more. As quartz oscillators are an essential element of nearly all types of frequency standards and reference systems, the success of MSAR would advance the development of frequency standards and systems for both groundbased and flight-based projects. Current quartz oscillator technology is limited by quartz mechanical Q. With a possible improvement of more than x 10 Q with sapphire acoustic modes, the stability limit of current quartz oscillators may be improved tenfold, to 10(exp -14) at 1 second. The electromagnetic modes of sapphire that were previously developed at JPL require cryogenic temperatures to achieve the high Q levels needed to achieve this stability level. However sapphire fs acoustic modes, which have not been used before in a high-stability oscillator, indicate the required Q values (as high as Q = 10(exp 8)) may be achieved at room temperature in the kHz range. Even though sapphire is not piezoelectric, such a high Q should allow electrostatic excitation of the acoustic modes with a combination of DC and AC voltages across a small sapphire disk (approximately equal to l mm thick). The first evaluations under this task will test predictions of an estimated input impedance of 10 kilohms at Q = 10(exp 8), and explore the Q values that can be realized in a smaller resonator, which has not been previously tested for acoustic modes. This initial Q measurement and excitation demonstration can be viewed similar to a transducer converting electrical energy to

  10. Efficient continuous-wave nonlinear frequency conversion in high-Q gallium nitride photonic crystal cavities on silicon

    NASA Astrophysics Data System (ADS)

    Mohamed, Mohamed Sabry; Simbula, Angelica; Carlin, Jean-François; Minkov, Momchil; Gerace, Dario; Savona, Vincenzo; Grandjean, Nicolas; Galli, Matteo; Houdré, Romuald

    2017-03-01

    We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave resonant excitation. Optimized two-dimensional PhC cavities with augmented far-field coupling have been characterized with quality factors as high as 4.4 × 104, approaching the computed theoretical values. The strong enhancement in light confinement has enabled efficient SHG, achieving a normalized conversion efficiency of 2.4 × 10-3 W-1, as well as simultaneous THG. SHG emission power of up to 0.74 nW has been detected without saturation. The results herein validate the suitability of gallium nitride for integrated nonlinear optical processing.

  11. Code System to Create Broad-Group Cross Sections with Resonance Interference and Self-Shielding from Fine-Group and Pointwise Cross Sections.

    SciTech Connect

    PELLONI, S.

    2007-10-31

    Version: 02 RSICC received MICROX‑2 through the NEADB (identifier is NEA‑1562/02.) This is an improved version of the original MICROX-2 two-region spectrum code, which was developed at General Atomic, to prepare broad group neutron cross sections for use in diffusion-and/or transport theory codes from an input library of fine group and pointwise cross sections. The MICROX-2 code can explicitly account for the overlap and interference effects between resonances in both the resonance and thermal neutron energy ranges and allows the simulta?neous treatment of leakage and resonance self-shielding in doubly heterogeneous lattice cells. MICROR runs as a module of NJOY 89.62; the NJOY calling module is included in the package. This release has been changed in that the MODER module from NJOY 94.0, too, has been included as subprogramm of NJOY 89.62, so as to make the code system completely selfconsistent, i.e. without requiring the use of some NJOY version to convert pendf and gendf from coded to binary. Using data from pointwise and groupwise NJOY tapes, the stand-alone MICROR reformatting program produces files containing basic nuclear data to be used by MICROX-2. MICROR edits PENDF and GENDF data files from NJOY to create FDTAP?E, GGTA?PE and GARTA?PE input files for MICROX-2. NJOY is not included in this package. Some data libraries are included for example cases; these data were generated from data in 193 groups as well as from point-wise cross sections from NJOY (Edition 89.62).

  12. Resonance-Enhanced Nonlinear Optical Effects

    NASA Astrophysics Data System (ADS)

    Sun, Xuan

    Nonlinear optical processes, which manifest as many interesting phenomena such as nonlinear wave mixing, optical rectification, intensity-dependent refractive index change, harmonic generation, etc., have found very broad applications. Unfortunately, most optical media exhibit rather weak optical nonlinearities and a majority of nonlinear optical processes have to rely on substantial optical powers to support nonlinear wave interactions, which becomes a major challenge for nonlinear photonic application. This thesis is devoted to exploring enhanced nonlinear optical phenomena, by taking advantage of a certain type of resonance to enhance the nonlinear wave interactions. For this purpose, we employed both natural atomic resonances via electron transition and engineered optical resonances in micro/nanophotonic device structures, for different applications. These two types of resonances, although distinctive in their physical natures, both are able to significantly increase the strength and elongate the time of optical wave interactions, thus leading to dramatic enhancement of nonlinear optical effects. On one hand, we utilized unique energy-level structures in alkali vapor plasmas to dramatically enhance the electron tunneling ionization process and to produce significant resonance-enhanced four-wave mixing for efficient terahertz (THz) wave generation that is crucial for long-wave application. On the other hand, we utilized the enhancement offered by high-Q optical resonances inside microresonators to produce significant photothermal backaction to dramatically suppress the fundamental temperature fluctuations of microresonators, which is essential for sensing and metrology applications. With such cavity-resonance enhancement, we revealed a new regime of nonlinear optical oscillation dynamics in lithium niobate microresonators that results from unique competition between the thermo-optic nonlinear effect and the photorefractive effect, which is inaccessible to

  13. Controlling normal incident optical waves with an integrated resonator.

    PubMed

    Qiu, Ciyuan; Xu, Qianfan

    2011-12-19

    We show a diffraction-based coupling scheme that allows a micro-resonator to directly manipulate a free-space optical beam at normal incidence. We demonstrate a high-Q micro-gear resonator with a 1.57-um radius whose vertical transmission and reflection change 40% over a wavelength range of only 0.3 nm. Without the need to be attached to a waveguide, a dense 2D array of such resonators can be integrated on a chip for spatial light modulation and parallel bio-sensing.

  14. Localized spoof surface plasmon resonances at terahertz range

    NASA Astrophysics Data System (ADS)

    Chen, Lin; Xu, Mengjian; Zang, Xiaofei; Peng, Yan; Zhu, Yiming

    2016-11-01

    The influence of the inner disk radius r, the filling ratio α, numbers of sectors N, and the gap g on transmission response for corrugated metallic disk (CMD) with single C-shaped resonator(CSR) has been fully studied. The results indicate that varying parameters r can efficiently excite the higher order spoof localized surface plasmon modes in corrugated metallic disk. The relationship between the bright dipole and dark multipolar resonances presents the possibility of high Q dark resonances excitation. All results may be of great interest for diverse applications.

  15. A Low-Noise CMOS THz Imager Based on Source Modulation and an In-Pixel High-Q Passive Switched-Capacitor N-Path Filter

    PubMed Central

    Boukhayma, Assim; Dupret, Antoine; Rostaing, Jean-Pierre; Enz, Christian

    2016-01-01

    This paper presents the first low noise complementary metal oxide semiconductor (CMOS) terahertz (THz) imager based on source modulation and in-pixel high-Q filtering. The 31×31 focal plane array has been fully integrated in a 0.13μm standard CMOS process. The sensitivity has been improved significantly by modulating the active THz source that lights the scene and performing on-chip high-Q filtering. Each pixel encompass a broadband bow tie antenna coupled to an N-type metal-oxide-semiconductor (NMOS) detector that shifts the THz radiation, a low noise adjustable gain amplifier and a high-Q filter centered at the modulation frequency. The filter is based on a passive switched-capacitor (SC) N-path filter combined with a continuous-time broad-band Gm-C filter. A simplified analysis that helps in designing and tuning the passive SC N-path filter is provided. The characterization of the readout chain shows that a Q factor of 100 has been achieved for the filter with a good matching between the analytical calculation and the measurement results. An input-referred noise of 0.2μV RMS has been measured. Characterization of the chip with different THz wavelengths confirms the broadband feature of the antenna and shows that this THz imager reaches a total noise equivalent power of 0.6 nW at 270 GHz and 0.8 nW at 600 GHz. PMID:26950131

  16. High quality-factor fano metasurface comprising a single resonator unit cell

    DOEpatents

    Sinclair, Michael B.; Warne, Larry K.; Basilio, Lorena I.; Langston, William L.; Campione, Salvatore; Brener, Igal; Liu, Sheng

    2017-06-20

    A new monolithic resonator metasurface design achieves ultra-high Q-factors while using only one resonator per unit cell. The metasurface relies on breaking the symmetry of otherwise highly symmetric resonators to induce intra-resonator mixing of bright and dark modes (rather than inter-resonator couplings), and is scalable from the near-infrared to radio frequencies and can be easily implemented in dielectric materials. The resulting high-quality-factor Fano metasurface can be used in many sensing, spectral filtering, and modulation applications.

  17. FUNDAMENTAL AREAS OF PHENOMENOLOGY (INCLUDING APPLICATIONS): Teleportation of Entangled States through Divorce of Entangled Pair Mediated by a Weak Coherent Field in a High-Q Cavity

    NASA Astrophysics Data System (ADS)

    Cardoso B., W.; Almeida G. de, N.

    2008-07-01

    We propose a scheme to partially teleport an unknown entangled atomic state. A high-Q cavity, supporting one mode of a weak coherent state, is needed to accomplish this process. By partial teleportation we mean that teleportation will occur by changing one of the partners of the entangled state to be teleported. The entangled state to be teleported is composed by one pair of particles, we called this surprising characteristic of maintaining the entanglement, even when one of the particle of the entangled pair being teleported is changed, of divorce of entangled states.

  18. High sensitivity and high Q-factor nanoslotted parallel quadrabeam photonic crystal cavity for real-time and label-free sensing

    SciTech Connect

    Yang, Daquan; Kita, Shota; Wang, Cheng; Lončar, Marko; Liang, Feng; Quan, Qimin; Tian, Huiping; Ji, Yuefeng

    2014-08-11

    We experimentally demonstrate a label-free sensor based on nanoslotted parallel quadrabeam photonic crystal cavity (NPQC). The NPQC possesses both high sensitivity and high Q-factor. We achieved sensitivity (S) of 451 nm/refractive index unit and Q-factor >7000 in water at telecom wavelength range, featuring a sensor figure of merit >2000, an order of magnitude improvement over the previous photonic crystal sensors. In addition, we measured the streptavidin-biotin binding affinity and detected 10 ag/mL concentrated streptavidin in the phosphate buffered saline solution.

  19. The Path to High Q-Factors in Superconducting Accelerating Cavities: Flux Expulsion and Surface Resistance Optimization

    SciTech Connect

    Martinello, Martina

    2016-12-01

    Accelerating cavities are devices resonating in the radio-frequency (RF) range used to accelerate charged particles in accelerators. Superconducting accelerating cavities are made out of niobium and operate at the liquid helium temperature. Even if superconducting, these resonating structures have some RF driven surface resistance that causes power dissipation. In order to decrease as much as possible the power losses, the cavity quality factor must be increased by decreasing the surface resistance. In this dissertation, the RF surface resistance is analyzed for a large variety of cavities made with different state-of-the-art surface treatments, with the goal of finding the surface treatment capable to return the highest Q-factor values in a cryomodule-like environment. This study analyzes not only the superconducting properties described by the BCS surface resistance, which is the contribution that takes into account dissipation due to quasi-particle excitations, but also the increasing of the surface resistance due to trapped flux. When cavities are cooled down below their critical temperature inside a cryomodule, there is always some remnant magnetic field that may be trapped increasing the global RF surface resistance. This thesis also analyzes how the fraction of external magnetic field, which is actually trapped in the cavity during the cooldown, can be minimized. This study is performed on an elliptical single-cell horizontally cooled cavity, resembling the geometry of cavities cooled in accelerator cryomodules. The horizontal cooldown study reveals that, as in case of the vertical cooldown, when the cooling is performed fast, large thermal gradients are created along the cavity helping magnetic flux expulsion. However, for this geometry the complete magnetic flux expulsion from the cavity equator is more difficult to achieve. This becomes even more challenging in presence of orthogonal magnetic field, that is easily trapped on top of the cavity equator

  20. The path to high Q-factors in superconducting accelerating cavities: Flux expulsion and surface resistance optimization

    NASA Astrophysics Data System (ADS)

    Martinello, Martina

    Accelerating cavities are devices resonating in the radio-frequency (RF) range used to accelerate charged particles in accelerators. Superconducting accelerating cavities are made out of niobium and operate at the liquid helium temperature. Even if superconducting, these resonating structures have some RF driven surface resistance that causes power dissipation. In order to decrease as much as possible the power losses, the cavity quality factor must be increased by decreasing the surface resistance. In this dissertation, the RF surface resistance is analyzed for a large variety of cavities made with different state-of-the-art surface treatments, with the goal of finding the surface treatment capable to return the highest Q-factor values in a cryomodule-like environment. This study analyzes not only the superconducting properties described by the BCS surface resistance, which is the contribution that takes into account dissipation due to quasi-particle excitations, but also the increasing of the surface resistance due to trapped flux. When cavities are cooled down below their critical temperature inside a cryomodule, there is always some remnant magnetic field that may be trapped increasing the global RF surface resistance. This thesis also analyzes how the fraction of external magnetic field, which is actually trapped in the cavity during the cooldown, can be minimized. This study is performed on an elliptical single-cell horizontally cooled cavity, resembling the geometry of cavities cooled in accelerator cryomodules. The horizontal cooldown study reveals that, as in case of the vertical cooldown, when the cooling is performed fast, large thermal gradients are created along the cavity helping magnetic flux expulsion. However, for this geometry the complete magnetic flux expulsion from the cavity equator is more difficult to achieve. This becomes even more challenging in presence of orthogonal magnetic field, that is easily trapped on top of the cavity equator

  1. Electron-electron double resonance (ELDOR) with a loop-gap resonator

    NASA Astrophysics Data System (ADS)

    Hyde, James S.; Yin, Jun-Jie; Froncisz, W.; Feix, Jimmy B.

    Electron-electron double-resonance (ELDOR) experiments on nitroxide-radical-spin-labeled liposomes have been performed using a loop-gap resonator. The signal-to-noise ratio expressed on a molarity basis is 20-fold over the best that has been achieved using a bimodal cavity. This improvement permits ELDOR experiments on spin-labeled plasma membranes of intact cells, as illustrated by a prototype experiment on red blood cells labeled with stearic acid spin label. Moreover, 20 times greater pumping energy density at the sample is achievable for a given incident pump power, permitting ELDOR experiments on less readily saturated systems. Pump and observing frequencies are introduced directly into the loop-gap resonator, which has a relatively low Q, and the pump electron paramagnetic resonance signal is isolated from the receiver using a high Q trap microwave filter.

  2. Biosensing by WGM Microspherical Resonators

    PubMed Central

    Righini, Giancarlo C.; Soria, Silvia

    2016-01-01

    Whispering gallery mode (WGM) microresonators, thanks to their unique properties, have allowed researchers to achieve important results in both fundamental research and engineering applications. Among the various geometries, microspheres are the simplest 3D WGM resonators; the total optical loss in such resonators can be extremely low, and the resulting extraordinarily high Q values of 108–109 lead to high energy density, narrow resonant-wavelength lines and a lengthy cavity ringdown. They can also be coated in order to better control their properties or to increase their functionality. Their very high sensitivity to changes in the surrounding medium has been exploited for several sensing applications: protein adsorption, trace gas detection, impurity detection in liquids, structural health monitoring of composite materials, detection of electric fields, pressure sensing, and so on. In the present paper, after a general introduction to WGM resonators, attention is focused on spherical microresonators, either in bulk or in bubble format, to their fabrication, characterization and functionalization. The state of the art in the area of biosensing is presented, and the perspectives of further developments are discussed. PMID:27322282

  3. Biosensing by WGM Microspherical Resonators.

    PubMed

    Righini, Giancarlo C; Soria, Silvia

    2016-06-17

    Whispering gallery mode (WGM) microresonators, thanks to their unique properties, have allowed researchers to achieve important results in both fundamental research and engineering applications. Among the various geometries, microspheres are the simplest 3D WGM resonators; the total optical loss in such resonators can be extremely low, and the resulting extraordinarily high Q values of 10⁸-10⁸ lead to high energy density, narrow resonant-wavelength lines and a lengthy cavity ringdown. They can also be coated in order to better control their properties or to increase their functionality. Their very high sensitivity to changes in the surrounding medium has been exploited for several sensing applications: protein adsorption, trace gas detection, impurity detection in liquids, structural health monitoring of composite materials, detection of electric fields, pressure sensing, and so on. In the present paper, after a general introduction to WGM resonators, attention is focused on spherical microresonators, either in bulk or in bubble format, to their fabrication, characterization and functionalization. The state of the art in the area of biosensing is presented, and the perspectives of further developments are discussed.

  4. Recoil polarization measurements of the proton form factor ratio GE^p/GM^p to high Q^2 in Hall C at Jefferson Lab

    NASA Astrophysics Data System (ADS)

    Puckett, Andrew

    2009-05-01

    Experiment E04-108 in Hall C at Jefferson Lab measured the ratio of the proton's electric (GE) and magnetic (GM) form factors using the recoil polarization technique at three different values of squared four-momentum transfer Q^2--5.2, 6.8, and 8.5 GeV^2. Data taking was completed in June 2008. Two new detectors were built by the collaboration to carry out this experiment. A large solid-angle electromagnetic calorimeter was used to detect elastically scattered electrons in coincidence with scattered protons detected by the Hall C High Momentum Spectrometer (HMS). The calorimeter allowed a clean rejection of the significant inelastic backgrounds present at such high Q^2. A new Focal Plane Polarimeter (FPP) was installed in the HMS detector hut to measure the polarization of the scattered proton. Following a discussion of the data analysis method, preliminary results will be reported.

  5. Optical Refractive Index Sensing Based on High-Q Bound States in the Continuum in Free-Space Coupled Photonic Crystal Slabs

    PubMed Central

    Liu, Yonghao; Zhou, Weidong

    2017-01-01

    High sensitivity (S) and high quality factor (Q) are desirable to achieve low detection limit in label-free optical sensors. In this paper, we theoretically demonstrate that single-layer and coupled bi-layer photonic crystal slabs (PCS) possess simultaneously high S and high Q near the bound states in the continuum (BIC). We theoretically achieved S > 800 nm/RIU and Q > 107 in refractive index sensing in the 1400–1600 nm telecom optical wavelength bands. We experimentally demonstrated an S of 94 nm/RIU and a Q of 1.2 × 104, with a detection limit of 6 × 10−5 refractive index unit. These sensor designs can find applications in biochemical sensing, environmental monitoring, and healthcare. PMID:28800108

  6. Optical Refractive Index Sensing Based on High-Q Bound States in the Continuum in Free-Space Coupled Photonic Crystal Slabs.

    PubMed

    Liu, Yonghao; Zhou, Weidong; Sun, Yuze

    2017-08-11

    High sensitivity (S) and high quality factor (Q) are desirable to achieve low detection limit in label-free optical sensors. In this paper, we theoretically demonstrate that single-layer and coupled bi-layer photonic crystal slabs (PCS) possess simultaneously high S and high Q near the bound states in the continuum (BIC). We theoretically achieved S > 800 nm/RIU and Q > 10⁷ in refractive index sensing in the 1400-1600 nm telecom optical wavelength bands. We experimentally demonstrated an S of 94 nm/RIU and a Q of 1.2 × 10⁴, with a detection limit of 6 × 10(-5) refractive index unit. These sensor designs can find applications in biochemical sensing, environmental monitoring, and healthcare.

  7. Silicon technology compatible photonic molecules for compact optical signal processing

    SciTech Connect

    Barea, Luis A. M. Vallini, Felipe; Jarschel, Paulo F.; Frateschi, Newton C.

    2013-11-11

    Photonic molecules (PMs) based on multiple inner coupled microring resonators allow to surpass the fundamental constraint between the total quality factor (Q{sub T}), free spectral range (FSR), and resonator size. In this work, we use a PM that presents doublets and triplets resonance splitting, all with high Q{sub T}. We demonstrate the use of the doublet splitting for 34.2 GHz signal extraction by filtering the sidebands of a modulated optical signal. We also demonstrate that very compact optical modulators operating 2.75 times beyond its resonator linewidth limit may be obtained using the PM triplet splitting, with separation of ∼55 GHz.

  8. Opto-fluidic ring resonator lasers based on highly efficient resonant energy transfer.

    PubMed

    Shopova, Siyka I; Cupps, Jay M; Zhang, Po; Henderson, Edward P; Lacey, Scott; Fan, Xudong

    2007-10-01

    We demonstrate an opto-fluidic ring resonator dye laser using highly efficient energy transfer. The active lasing material consists of a donor and acceptor mixture and flows in a fused silica capillary whose circular cross section forms a ring resonator and supports the whispering gallery modes (WGMs) of high Q-factors (>107). The excited states are created in the donor and transferred to the acceptor through the fluorescence resonant energy transfer (FRET), whose emission is coupled into the WGM. Due to the high energy transfer efficiency and high Q-factors, the acceptor exhibits a lasing threshold as low as 0.3 muJ/mm2. We further analyze the energy transfer mechanisms and find that non-radiative Förster transfer is the dominant effect to support the acceptor lasing. FRET lasers using cascade energy transfer and using quantum dots (QDs) as the donor are also presented. Our study will not only lead to development of novel microfluidic lasers with low lasing thresholds and excitation/emission flexibility, but also open an avenue for future laser intra-cavity bio/chemical sensing.

  9. Tunable optical analog to electromagnetically induced transparency in graphene-ring resonators system

    NASA Astrophysics Data System (ADS)

    Wang, Yonghua; Xue, Chenyang; Zhang, Zengxing; Zheng, Hua; Zhang, Wendong; Yan, Shubin

    2016-12-01

    The analogue of electromagnetically induced transparency in optical ways has shown great potential in optical delay and quantum-information technology due to its flexible design and easy implementation. The chief drawback for these devices is the bad tunability. Here we demonstrate a tunable optical transparency system formed by graphene-silicon microrings which could control the transparent window by electro-optical means. The device consists of cascaded coupled ring resonators and a graphene/graphene capacitor which integrated on one of the rings. By tuning the Fermi level of the graphene sheets, we can modulate the round-trip ring loss so that the transparency window can be dynamically tuned. The results provide a new method for the manipulation and transmission of light in highly integrated optical circuits and quantum information storage devices.

  10. Tunable optical analog to electromagnetically induced transparency in graphene-ring resonators system.

    PubMed

    Wang, Yonghua; Xue, Chenyang; Zhang, Zengxing; Zheng, Hua; Zhang, Wendong; Yan, Shubin

    2016-12-12

    The analogue of electromagnetically induced transparency in optical ways has shown great potential in optical delay and quantum-information technology due to its flexible design and easy implementation. The chief drawback for these devices is the bad tunability. Here we demonstrate a tunable optical transparency system formed by graphene-silicon microrings which could control the transparent window by electro-optical means. The device consists of cascaded coupled ring resonators and a graphene/graphene capacitor which integrated on one of the rings. By tuning the Fermi level of the graphene sheets, we can modulate the round-trip ring loss so that the transparency window can be dynamically tuned. The results provide a new method for the manipulation and transmission of light in highly integrated optical circuits and quantum information storage devices.

  11. Tunable optical analog to electromagnetically induced transparency in graphene-ring resonators system

    PubMed Central

    Wang, Yonghua; Xue, Chenyang; Zhang, Zengxing; Zheng, Hua; Zhang, Wendong; Yan, Shubin

    2016-01-01

    The analogue of electromagnetically induced transparency in optical ways has shown great potential in optical delay and quantum-information technology due to its flexible design and easy implementation. The chief drawback for these devices is the bad tunability. Here we demonstrate a tunable optical transparency system formed by graphene-silicon microrings which could control the transparent window by electro-optical means. The device consists of cascaded coupled ring resonators and a graphene/graphene capacitor which integrated on one of the rings. By tuning the Fermi level of the graphene sheets, we can modulate the round-trip ring loss so that the transparency window can be dynamically tuned. The results provide a new method for the manipulation and transmission of light in highly integrated optical circuits and quantum information storage devices. PMID:27941895

  12. Photonic compressive sensing with a micro-ring-resonator-based microwave photonic filter

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Ding, Yunhong; Zhu, Zhijing; Chi, Hao; Zheng, Shilie; Zhang, Xianmin; Jin, Xiaofeng; Galili, Michael; Yu, Xianbin

    2016-08-01

    A novel approach to realize photonic compressive sensing (CS) with a multi-tap microwave photonic filter is proposed and demonstrated. The system takes both advantages of CS and photonics to capture wideband sparse signals with sub-Nyquist sampling rate. The low-pass filtering function required in the CS is realized in a photonic way by using a frequency comb and a dispersive element. The frequency comb is realized by shaping an amplified spontaneous emission (ASE) source with an on-chip micro-ring resonator, which is beneficial to the integration of photonic CS. A proof-of-concept experiment for a two-tone signal acquisition with frequencies of 350 MHz and 1.25 GHz is experimentally demonstrated with a compression factor up to 16.

  13. Active and Passive Coupled-Resonator Optical Waveguides

    NASA Astrophysics Data System (ADS)

    Poon, Joyce Kai See

    Coupled-Resonator Optical Waveguides (CROWs) are chains of resonators in which light propagates by virtue of the coupling between the resonators. The dispersive properties of these waveguides are controllable by the inter-resonator coupling and the geometry of the resonators. If the inter-resonator coupling is weak, light can be engineered to propagate slowly in these structures. The small group velocities possible in CROWs may enable applications in and technologies for optical delay lines, interferometers, buffers, nonlinear optics, and lasers. This thesis reports on achieving and controlling the optical delay in passive and active CROWs. Both theoretical and experimental results are presented. Transfer matrices, tight-binding models, and coupled-mode approaches are developed to analyze and design a variety of coupled resonator systems in the space, frequency, and time domains. Although each analytical method is fundamentally different, in the limit of weak inter-resonator coupling these approaches are consistent with each other. From these formalisms, simple expressions for the delay, loss, bandwidth, and a figure of merit are derived to compare the performance of CROW delay lines. Using a time-domain tight-binding model, we examine the resonant gain enhancement and spontaneous emission noise in amplifying CROWs to find that the net amplification of a propagating wave does not always vary with the group velocity but instead depends on the termination and excitation of the CROW. CROWs in the form of high-order (> 10) weakly coupled passive polymer microring resonators were fabricated and measured. The measured transmission, group delay, and dispersive properties of the CROWs agreed with the theoretical results. Delays in excess of 100 ps and slowing factors of about 25 over bandwidths of about 20 GHz were observed. The main limitation of the passive CROWs was the optical losses. To overcome the losses and to enable electrical integration, we demonstrated active

  14. High sensitivity optical waveguide accelerometer based on Fano resonance.

    PubMed

    Wan, Fenghua; Qian, Guang; Li, Ruozhou; Tang, Jie; Zhang, Tong

    2016-08-20

    An optical waveguide accelerometer based on tunable asymmetrical Fano resonance in a ring-resonator-coupled Mach-Zehnder interferometer (MZI) is proposed and analyzed. A Fano resonance accelerometer has a relatively large workspace of coupling coefficients with high sensitivity, which has potential application in inertial navigation, missile guidance, and attitude control of satellites. Due to the interference between a high-Q resonance pathway and a coherent background pathway, a steep asymmetric line shape is generated, which greatly improves the sensitivity of this accelerometer. The sensitivity of the accelerometer is about 111.75 mW/g. A 393-fold increase in sensitivity is achieved compared with a conventional MZI accelerometer and is approximately equal to the single ring structure.

  15. Diffraction Theory of Two-Mirror Echelette Resonators

    NASA Astrophysics Data System (ADS)

    Vlasov, S. N.; Koposova, E. V.

    2016-09-01

    We develop the theory of a two-mirror resonator, in which one mirror is an echelette diffraction grating. The diffraction loss related to the finite sizes of the mirrors, the loss determined by the existence of a mirror diffraction maximum of the grating (coupling loss), and the ohmic loss are taken into account. We show the possibility of constructing a resonator with one high-Q mode in a wide frequency band. This mode can be used as the working mode of a gyrotron operated at the second gyrofrequency harmonic, which interacts efficiently with the electron beam. We also demonstrate the possibility of frequency tuning of the resonator in a frequency band of 1%, while retaining the parameters which are satisfactory for gyrotron operation, and a high degree of resonator selectivity (i.e., the presence of a single mode).

  16. Optical resonator

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    The invention discloses a semi-ring Fabry-Perot (SRFP) optical resonator structure comprising a medium including an edge forming a reflective facet and a waveguide within the medium, the waveguide having opposing ends formed by the reflective facet. The performance of the SRFP resonator can be further enhanced by including a Mach-Zehnder interferometer in the waveguide on one side of the gain medium. The optical resonator can be employed in a variety of optical devices. Laser structures using at least one SRFP resonator are disclosed where the resonators are disposed on opposite sides of a gain medium. Other laser structures employing one or more resonators on one side of a gain region are also disclosed.

  17. Snake resonances

    SciTech Connect

    Tepikian, S.

    1988-01-01

    Siberian Snakes provide a practical means of obtaining polarized proton beams in large accelerators. The effect of snakes can be understood by studying the dynamics of spin precession in an accelerator with snakes and a single spin resonance. This leads to a new class of energy independent spin depolarizing resonances, called snake resonances. In designing a large accelerator with snakes to preserve the spin polarization, there is an added constraint on the choice of the vertical betatron tune due to the snake resonances. 11 refs., 4 figs.

  18. Proof-of-principle demonstration of Nb{sub 3}Sn superconducting radiofrequency cavities for high Q{sub 0} applications

    SciTech Connect

    Posen, S. Liepe, M.; Hall, D. L.

    2015-02-23

    Many future particle accelerators require hundreds of superconducting radiofrequency (SRF) cavities operating with high duty factor. The large dynamic heat load of the cavities causes the cryogenic plant to make up a significant part of the overall cost of the facility. This contribution can be reduced by replacing standard niobium cavities with ones coated with a low-dissipation superconductor such as Nb{sub 3}Sn. In this paper, we present results for single cell cavities coated with Nb{sub 3}Sn at Cornell. Five coatings were carried out, showing that at 4.2 K, high Q{sub 0} out to medium fields was reproducible, resulting in an average quench field of 14 MV/m and an average 4.2 K Q{sub 0} at quench of 8 × 10{sup 9}. In each case, the peak surface magnetic field at quench was well above H{sub c1}, showing that it is not a limiting field in these cavities. The coating with the best performance had a quench field of 17 MV/m, exceeding gradient requirements for state-of-the-art high duty factor SRF accelerators. It is also shown that—taking into account the thermodynamic efficiency of the cryogenic plant—the 4.2 K Q{sub 0} values obtained meet the AC power consumption requirements of state-of-the-art high duty factor accelerators, making this a proof-of-principle demonstration for Nb{sub 3}Sn cavities in future applications.

  19. Label-free photonic biosensors fabricated with low-loss hydrogenated amorphous silicon resonators

    NASA Astrophysics Data System (ADS)

    Lipka, Timo; Wahn, Lennart; Trieu, Hoc Khiem; Hilterhaus, Lutz; Müller, Jörg

    2013-01-01

    The precise detection of chemicals and biomolecules is of great interest in the areas of biotechnology and medical diagnostics. Thus, there is a need for highly sensitive, small area, and low-cost sensors. We fabricated and optically characterized hydrogenated amorphous silicon photonic resonators for label-free lab-on-chip biosensors. The sensing was performed with small-footprint microdisk and microring resonators that detect a refractive-index change via the evanescent electric field. Homogeneous sensing with NaCl and surface-sensing experiments with immobilized bovine serum albumin (BSA) were carried out. A sensitivity as high as 460 nm/RIU was measured for NaCl dissolved in deionized water for the disk, whereas about 50 nm/RIU was determined for the ring resonator. The intrinsic limits of detection were calculated to be 3.3×10 and 3.2×10 at 1550-nm wavelength. We measured the binding of BSA to functionalized ring resonators and found that molecular masses can be detected down to the clinically relevant femtogram regime. The detection and quantification of related analytes with hydrogenated amorphous silicon photonic sensors can be used in medical healthcare diagnostics like point-of-care-testing and biotechnological screening.

  20. Nonlinear resonance

    NASA Astrophysics Data System (ADS)

    Kevorkian, J.

    This report discusses research in the area of slowly varying nonlinear oscillatory systems. Some of the topics discussed are as follows: adiabatic invariants and transient resonance in very slowly varying Hamiltonian systems; sustained resonance in very slowly varying Hamiltonian systems; free-electron lasers with very slow wiggler taper; and bursting oscillators.