Narrowing the filter-cavity bandwidth in gravitational-wave detectors via optomechanical interaction.

PubMed

Ma, Yiqiu; Danilishin, Shtefan L; Zhao, Chunnong; Miao, Haixing; Korth, W Zach; Chen, Yanbei; Ward, Robert L; Blair, D G

2014-10-10

We propose using optomechanical interaction to narrow the bandwidth of filter cavities for achieving frequency-dependent squeezing in advanced gravitational-wave detectors, inspired by the idea of optomechanically induced transparency. This can allow us to achieve a cavity bandwidth on the order of 100 Hz using small-scale cavities. Additionally, in contrast to a passive Fabry-Pérot cavity, the resulting cavity bandwidth can be dynamically tuned, which is useful for adaptively optimizing the detector sensitivity when switching amongst different operational modes. The experimental challenge for its implementation is a stringent requirement for very low thermal noise of the mechanical oscillator, which would need a superb mechanical quality factor and a very low temperature. We consider one possible setup to relieve this requirement by using optical dilution to enhance the mechanical quality factor.

Nano-optomechanical system based on microwave frequency surface acoustic waves

NASA Astrophysics Data System (ADS)

Tadesse, Semere Ayalew

Cavity optomechnics studies the interaction of cavity confined photons with mechanical motion. The emergence of sophisticated nanofabrication technology has led to experimental demonstrations of a wide range of novel optomechanical systems that exhibit strong optomechanical coupling and allow exploration of interesting physical phenomena. Many of the studies reported so far are focused on interaction of photons with localized mechanical modes. For my doctoral research, I did experimental investigations to extend this study to propagating phonons. I used surface travelling acoustic waves as the mechanical element of my optomechanical system. The optical cavities constitute an optical racetrack resonator and photonic crystal nanocavity. This dissertation discusses implementation of this surface acoustic wave based optomechanical system and experimental demonstrations of important consequences of the optomechanical coupling. The discussion focuses on three important achievements of the research. First, microwave frequency surface acoustic wave transducers were co-integrated with an optical racetrack resonator on a piezoelectric aluminum nitride film deposited on an oxidized silicon substrate. Acousto-optic modulation of the resonance modes at above 10 GHz with the acoustic wavelength significantly below the optical wavelength was achieved. The phase and modal matching conditions in this paradigm were investigated for efficient optmechanical coupling. Second, the optomechanical coupling was pushed further into the sideband resolved regime by integrating the high frequency surface acoustic wave transducers with a photonic crystal nanocavity. This device was used to demonstrate optomecahnically induced transparency and absorption, one of the interesting consequences of cavity optomechanics. Phase coherent interaction of the acoustic wave with multiple nanocavities was also explored. In a related experiment, the photonic crystal nanoscavity was placed inside an acoustic

Quantum noise spectra for periodically driven cavity optomechanics

NASA Astrophysics Data System (ADS)

Aranas, E. B.; Akram, M. Javed; Malz, Daniel; Monteiro, T. S.

2017-12-01

A growing number of experimental setups in cavity optomechanics exploit periodically driven fields. However, such setups are not amenable to analysis by using simple, yet powerful, closed-form expressions of linearized optomechanics, which have provided so much of our present understanding of experimental optomechanics. In the present paper, we formulate a method to calculate quantum noise spectra in modulated optomechanical systems, which we analyze, compare, and discuss with two other recently proposed solutions: we term these (i) frequency-shifted operators, (ii) Floquet [Phys. Rev. A 94, 023803 (2016), 10.1103/PhysRevA.94.023803], and (iii) iterative analysis [New J. Phys. 18, 113021 (2016), 10.1088/1367-2630/18/11/113021]. We prove that (i) and (ii) yield equivalent noise spectra and find that (iii) is an analytical approximation to (i) for weak modulations. We calculate the noise spectra of a doubly modulated system describing experiments of levitated particles in hybrid electro-optical traps. We show excellent agreement with Langevin stochastic simulations in the thermal regime and predict squeezing in the quantum regime. Finally, we reveal how otherwise-inaccessible spectral components of a modulated system can be measured in heterodyne detection through an appropriate choice of modulation frequencies.

Two-fluid model of a Bose-Einstein condensate in the cavity optomechanical regime

NASA Astrophysics Data System (ADS)

Goldbaum, Dan; Zhang, Keye; Meystre, Pierre

2010-03-01

We analyze an atomic Bose-Einstein condensate trapped in a high-Q optical cavity driven by a feeble optical field. The dynamics of the resulting collective density excitation of the condensate are formally analogous to the central model system of cavity optomechanics: a radiation pressure driven mechanical oscillator [Brennecke et al., Science 322, 235 (2008)]. However, although BEC-based optomechanical systems have several desirable properties, one must also take into account the effect of atom-atom interactions. We treat these interactions via a two-fluid model that retains the intuitive appeal of the non-interacting two-mode description. We find that the Bogoliubov excitation spectrum of this system comprises a gapped upper branch and a lower branch that can include an unstable excitation mode. [4pt] D. S. Goldbaum, K. Zhang and P. Meystre, Two-fluid model of a Bose-Einstein condensate in the cavity optomechanical regime, arXiv:0911.3234.

Magnetic actuation and feedback cooling of a cavity optomechanical torque sensor.

PubMed

Kim, P H; Hauer, B D; Clark, T J; Fani Sani, F; Freeman, M R; Davis, J P

2017-11-07

Cavity optomechanics has demonstrated remarkable capabilities, such as measurement and control of mechanical motion at the quantum level. Yet many compelling applications of optomechanics-such as microwave-to-telecom wavelength conversion, quantum memories, materials studies, and sensing applications-require hybrid devices, where the optomechanical system is coupled to a separate, typically condensed matter, system. Here, we demonstrate such a hybrid optomechanical system, in which a mesoscopic ferromagnetic needle is integrated with an optomechanical torsional resonator. Using this system we quantitatively extract the magnetization of the needle, not known a priori, demonstrating the potential of this system for studies of nanomagnetism. Furthermore, we show that we can magnetically dampen its torsional mode from room-temperature to 11.6 K-improving its mechanical response time without sacrificing torque sensitivity. Future extensions will enable studies of high-frequency spin dynamics and broadband wavelength conversion via torque mixing.

Coherent coupling between radio frequency, optical, and acoustic waves in piezo-optomechanical circuits

PubMed Central

Balram, Krishna C.; Davanço, Marcelo I.; Song, Jin Dong; Srinivasan, Kartik

2016-01-01

Optomechanical cavities have been studied for applications ranging from sensing to quantum information science. Here, we develop a platform for nanoscale cavity optomechanical circuits in which optomechanical cavities supporting co-localized 1550 nm photons and 2.4 GHz phonons are combined with photonic and phononic waveguides. Working in GaAs facilitates manipulation of the localized mechanical mode either with a radio frequency (RF) field through the piezo-electric effect, which produces acoustic waves that are routed and coupled to the optomechanical cavity by phononic crystal waveguides, or optically through the strong photoelastic effect. Along with mechanical state preparation and sensitive readout, we use this to demonstrate an acoustic wave interference effect, similar to atomic coherent population trapping, in which RF-driven coherent mechanical motion is cancelled by optically-driven motion. Manipulating cavity optomechanical systems with equal facility through both photonic and phononic channels enables new architectures for signal transduction between the optical, electrical, and mechanical domains. PMID:27446234

Quantum optics, cavity QED, and quantum optomechanics

NASA Astrophysics Data System (ADS)

Meystre, Pierre

2013-05-01

Quantum optomechanics provides a universal tool to achieve the quantum control of mechanical motion. It does that in devices spanning a vast range of parameters, with mechanical frequencies from a few Hertz to GHz, and with masses from 10-20 g to several kilos. Its underlying ideas can be traced back to the study of gravitational wave antennas, quantum optics, cavity QED and laser cooling which, when combined with the recent availability of advanced micromechanical and nanomechanical devices, opens a path to the realization of macroscopic mechanical systems that operate deep in the quantum regime. At the fundamental level this development paves the way to experiments that will lead to a more profound understanding of quantum mechanics; and from the point of view of applications, quantum optomechanical techniques will provide motion and force sensing near the fundamental limit imposed by quantum mechanics (quantum metrology) and significantly expand the toolbox of quantum information science. After a brief summary of key historical developments, the talk will give a broad overview of the current state of the art of quantum optomechanics, and comment on future prospects both in applied and in fundamental science. Work supported by NSF, ARO and the DARPA QuASAR and ORCHID programs.

Non-classical light generated by quantum-noise-driven cavity optomechanics.

PubMed

Brooks, Daniel W C; Botter, Thierry; Schreppler, Sydney; Purdy, Thomas P; Brahms, Nathan; Stamper-Kurn, Dan M

2012-08-23

Optomechanical systems, in which light drives and is affected by the motion of a massive object, will comprise a new framework for nonlinear quantum optics, with applications ranging from the storage and transduction of quantum information to enhanced detection sensitivity in gravitational wave detectors. However, quantum optical effects in optomechanical systems have remained obscure, because their detection requires the object’s motion to be dominated by vacuum fluctuations in the optical radiation pressure; so far, direct observations have been stymied by technical and thermal noise. Here we report an implementation of cavity optomechanics using ultracold atoms in which the collective atomic motion is dominantly driven by quantum fluctuations in radiation pressure. The back-action of this motion onto the cavity light field produces ponderomotive squeezing. We detect this quantum phenomenon by measuring sub-shot-noise optical squeezing. Furthermore, the system acts as a low-power, high-gain, nonlinear parametric amplifier for optical fluctuations, demonstrating a gain of 20 dB with a pump corresponding to an average of only seven intracavity photons. These findings may pave the way for low-power quantum optical devices, surpassing quantum limits on position and force sensing, and the control and measurement of motion in quantum gases.

Bulk crystalline optomechanics

NASA Astrophysics Data System (ADS)

Renninger, W. H.; Kharel, P.; Behunin, R. O.; Rakich, P. T.

2018-06-01

Control of long-lived, high-frequency phonons using light offers a path towards creating robust quantum links, and could lead to tools for precision metrology with applications to quantum information processing. Optomechanical systems based on bulk acoustic-wave resonators are well suited for this goal in light of their high quality factors, and because they do not suffer from surface interactions as much as their microscale counterparts. However, so far these phonons have been accessible only electromechanically, using piezoelectric interactions. Here, we demonstrate customizable optomechanical coupling to macroscopic phonon modes of a bulk acoustic-wave resonator at cryogenic temperatures. These phonon modes, which are formed by shaping the surfaces of a crystal into a plano-convex phononic resonator, yield appreciable optomechanical coupling rates, providing access to high acoustic quality factors (4.2 × 107) at high phonon frequencies (13 GHz). This simple approach, which uses bulk properties rather than nanostructural control, is appealing for the ability to engineer optomechanical systems at high frequencies that are robust against thermal decoherence. Moreover, we show that this optomechanical system yields a unique form of dispersive symmetry-breaking that enables phonon heating or cooling without an optical cavity.

Nonlinear cavity optomechanics with nanomechanical thermal fluctuations

PubMed Central

Leijssen, Rick; La Gala, Giada R.; Freisem, Lars; Muhonen, Juha T.; Verhagen, Ewold

2017-01-01

Although the interaction between light and motion in cavity optomechanical systems is inherently nonlinear, experimental demonstrations to date have allowed a linearized description in all except highly driven cases. Here, we demonstrate a nanoscale optomechanical system in which the interaction between light and motion is so large (single-photon cooperativity C0≈103) that thermal motion induces optical frequency fluctuations larger than the intrinsic optical linewidth. The system thereby operates in a fully nonlinear regime, which pronouncedly impacts the optical response, displacement measurement and radiation pressure backaction. Specifically, we measure an apparent optical linewidth that is dominated by thermo-mechanically induced frequency fluctuations over a wide temperature range, and show that in this regime thermal displacement measurements cannot be described by conventional analytical models. We perform a proof-of-concept demonstration of exploiting the nonlinearity to conduct sensitive quadratic readout of nanomechanical displacement. Finally, we explore how backaction in this regime affects the mechanical fluctuation spectra. PMID:28685755

Laser optomechanics

NASA Astrophysics Data System (ADS)

Yang, Weijian; Adair Gerke, Stephen; Wei Ng, Kar; Rao, Yi; Chase, Christopher; Chang-Hasnain, Connie J.

2015-09-01

Cavity optomechanics explores the interaction between optical field and mechanical motion. So far, this interaction has relied on the detuning between a passive optical resonator and an external pump laser. Here, we report a new scheme with mutual coupling between a mechanical oscillator supporting the mirror of a laser and the optical field generated by the laser itself. The optically active cavity greatly enhances the light-matter energy transfer. In this work, we use an electrically-pumped vertical-cavity surface-emitting laser (VCSEL) with an ultra-light-weight (130 pg) high-contrast-grating (HCG) mirror, whose reflectivity spectrum is designed to facilitate strong optomechanical coupling, to demonstrate optomechanically-induced regenerative oscillation of the laser optomechanical cavity. We observe >550 nm self-oscillation amplitude of the micromechanical oscillator, two to three orders of magnitude larger than typical, and correspondingly a 23 nm laser wavelength sweep. In addition to its immediate applications as a high-speed wavelength-swept source, this scheme also offers a new approach for integrated on-chip sensors.

Suppression of extraneous thermal noise in cavity optomechanics.

PubMed

Zhao, Yi; Wilson, Dalziel J; Ni, K-K; Kimble, H J

2012-02-13

Extraneous thermal motion can limit displacement sensitivity and radiation pressure effects, such as optical cooling, in a cavity-optomechanical system. Here we present an active noise suppression scheme and its experimental implementation. The main challenge is to selectively sense and suppress extraneous thermal noise without affecting motion of the oscillator. Our solution is to monitor two modes of the optical cavity, each with different sensitivity to the oscillator's motion but similar sensitivity to the extraneous thermal motion. This information is used to imprint "anti-noise" onto the frequency of the incident laser field. In our system, based on a nano-mechanical membrane coupled to a Fabry-Pérot cavity, simulation and experiment demonstrate that extraneous thermal noise can be selectively suppressed and that the associated limit on optical cooling can be reduced.

Cooling in the single-photon strong-coupling regime of cavity optomechanics

NASA Astrophysics Data System (ADS)

Nunnenkamp, A.; Børkje, K.; Girvin, S. M.

2012-05-01

In this Rapid Communication we discuss how red-sideband cooling is modified in the single-photon strong-coupling regime of cavity optomechanics where the radiation pressure of a single photon displaces the mechanical oscillator by more than its zero-point uncertainty. Using Fermi's golden rule we calculate the transition rates induced by the optical drive without linearizing the optomechanical interaction. In the resolved-sideband limit we find multiple-phonon cooling resonances for strong single-photon coupling that lead to nonthermal steady states including the possibility of phonon antibunching. Our study generalizes the standard linear cooling theory.

Optomechanical and photothermal interactions in suspended photonic crystal membranes.

PubMed

Woolf, David; Hui, Pui-Chuen; Iwase, Eiji; Khan, Mughees; Rodriguez, Alejandro W; Deotare, Parag; Bulu, Irfan; Johnson, Steven G; Capasso, Federico; Loncar, Marko

2013-03-25

We present here an optomechanical system fabricated with novel stress management techniques that allow us to suspend an ultrathin defect-free silicon photonic-crystal membrane above a Silicon-on-Insulator (SOI) substrate with a gap that is tunable to below 200 nm. Our devices are able to generate strong attractive and repulsive optical forces over a large surface area with simple in- and out- coupling and feature the strongest repulsive optomechanical coupling in any geometry to date (gOM/2π ≈65 GHz/nm). The interplay between the optomechanical and photo-thermal-mechanical dynamics is explored, and the latter is used to achieve cooling and amplification of the mechanical mode, demonstrating that our platform is well-suited for potential applications in low-power mass, force, and refractive-index sensing as well as optomechanical accelerometry.

Optoelectronic forces with quantum wells for cavity optomechanics in GaAs/AlAs semiconductor microcavities

NASA Astrophysics Data System (ADS)

Villafañe, V.; Sesin, P.; Soubelet, P.; Anguiano, S.; Bruchhausen, A. E.; Rozas, G.; Carbonell, C. Gomez; Lemaître, A.; Fainstein, A.

2018-05-01

Radiation pressure, electrostriction, and photothermal forces have been investigated to evidence backaction, nonlinearities, and quantum phenomena in cavity optomechanics. We show here through a detailed study of the relative intensity of the cavity mechanical modes observed when exciting with pulsed lasers close to the GaAs optical gap that optoelectronic forces involving real carrier excitation and deformation potential interaction are the strongest mechanism of light-to-sound transduction in semiconductor GaAs/AlAs distributed Bragg reflector optomechanical resonators. We demonstrate that the ultrafast spatial redistribution of the photoexcited carriers in microcavities with massive GaAs spacers leads to an enhanced coupling to the fundamental 20-GHz vertically polarized mechanical breathing mode. The carrier diffusion along the growth axis of the device can be enhanced by increasing the laser power, or limited by embedding GaAs quantum wells in the cavity spacer, a strategy used here to prove and engineer the optoelectronic forces in phonon generation with real carriers. The wavelength dependence of the observed phenomena provide further proof of the role of optoelectronic forces. The optical forces associated with the different intervening mechanisms and their relevance for dynamical backaction in optomechanics are evaluated using finite-element methods. The results presented open the path to the study of hitherto seldom investigated dynamical backaction in optomechanical solid-state resonators in the presence of optoelectronic forces.

Levitated optomechanics with a fiber Fabry-Perot interferometer

NASA Astrophysics Data System (ADS)

Pontin, A.; Mourounas, L. S.; Geraci, A. A.; Barker, P. F.

2018-02-01

In recent years, quantum phenomena have been experimentally demonstrated on variety of optomechanical systems ranging from micro-oscillators to photonic crystals. Since single photon couplings are quite small, most experimental approaches rely on the realization of high finesse Fabry-Perot cavities in order to enhance the effective coupling. Here we show that by exploiting a, long path, low finesse fiber Fabry-Perot interferometer ground state cooling can be achieved. We model a 100 m long cavity with a finesse of 10 and analyze the impact of additional noise sources arising from the fiber. As a mechanical oscillator we consider a levitated microdisk but the same approach could be applied to other optomechanical systems.

Controlling single-photon transport in an optical waveguide coupled to an optomechanical cavity with a Λ-type three-level atom

NASA Astrophysics Data System (ADS)

Zhang, Yu-Qing; Zhu, Zhong-Hua; Peng, Zhao-Hui; Jiang, Chun-Lei; Chai, Yi-Feng; Hai, Lian; Tan, Lei

2018-06-01

We theoretically study the single-photon transport along a one-dimensional optical waveguide coupled to an optomechanical cavity containing a Λ-type three-level atom. Our numerical results show that the transmission spectra of the incident photon can be well controlled by such a hybrid atom-optomechanical system. The effects of the optomechanical coupling strength, the classical laser beam applied to the atom, atom-cavity detuning, and atomic dissipation on the single-photon transport properties are analyzed. It is of particular interest that an analogous double electromagnetically induced transparency emerges in the single-photon transmission spectra.

Cavity Optomechanics: Coherent Coupling of Light and Mechanical Oscillators

NASA Astrophysics Data System (ADS)

Kippenberg, Tobias J.

2012-06-01

The mutual coupling of optical and mechanical degrees of freedom via radiation pressure has been a subject of interest in the context of quantum limited displacements measurements for Gravity Wave Detection for many decades, however light forces have remained experimentally unexplored in such systems. Recent advances in nano- and micro-mechanical oscillators have for the first time allowed the observation of radiation pressure phenomena in an experimental setting and constitute the expanding research field of cavity optomechanics [1]. These advances have allowed achieving to enter the quantum regime of mechanical systems, which are now becoming a third quantum technology after atoms, ions and molecules in a first and electronic circuits in a second wave. In this talk I will review these advances. Using on-chip micro-cavities that combine both optical and mechanical degrees of freedom in one and the same device [2], radiation pressure back-action of photons is shown to lead to effective cooling [3-6]) of the mechanical oscillator mode using dynamical backaction, which has been predicted by Braginsky as early as 1969 [4]. This back-action cooling exhibits many close analogies to atomic laser cooling. With this novel technique the quantum mechanical ground state of a micromechanical oscillator has been prepared with high probability using both microwave and optical fields. In our research this is reached using cryogenic precooling to ca. 800 mK in conjunction with laser cooling, allowing cooling of micromechanical oscillator to only motional 1.7 quanta, implying that the mechanical oscillator spends about 40% of its time in the quantum ground state. Moreover it is possible in this regime to observe quantum coherent coupling in which the mechanical and optical mode hybridize and the coupling rate exceeds the mechanical and optical decoherence rate [7]. This accomplishment enables a range of quantum optical experiments, including state transfer from light to mechanics

Two-mode back-action-evading measurements in cavity optomechanics

NASA Astrophysics Data System (ADS)

Woolley, M. J.; Clerk, A. A.

2013-06-01

We study theoretically a three-mode optomechanical system where two mechanical oscillators are coupled to a single cavity mode. By using two-tone (i.e., amplitude-modulated) driving of the cavity, it is possible to couple the cavity to a single collective quadrature of the mechanical oscillators. In such a way, a back-action-evading measurement of the collective mechanical quadrature is possible. We discuss how this can allow one to measure both quadratures of a mechanical force beyond the full quantum limit, paying close attention to the role of dissipation and experimental imperfections. We also describe how this scheme allows one to generate steady-state mechanical entanglement; namely, one can conditionally prepare an entangled, two-mode squeezed mechanical state. This entanglement can be verified directly from the measurement record by applying a generalized version of Duan's inequality; we also discuss how feedback can be used to produce unconditional entanglement.

Absorption, Transmission and Amplification in a Double-Cavity Optomechanical System with Coulomb-Interaction

NASA Astrophysics Data System (ADS)

Geng, H.; Liu, H. D.

2018-04-01

We explore three interesting phenomena in a double-cavity optomechanical system: coherent perfect absorption, coherent perfect transmission and output signal amplification, and find that these phenomena can be realized and controlled by the coulomb-interaction between the dissipative oscillator locates in the cavity and the gain oscillator locates outside. They originate from the efficient hybrid coupling of optical and mechanical modes, and can be used for realizing novel photonic devices in quantum information networks.

All optical reconfiguration of optomechanical filters.

PubMed

Deotare, Parag B; Bulu, Irfan; Frank, Ian W; Quan, Qimin; Zhang, Yinan; Ilic, Rob; Loncar, Marko

2012-05-22

Reconfigurable optical filters are of great importance for applications in optical communication and information processing. Of particular interest are tuning techniques that take advantage of mechanical deformation of the devices, as they offer wider tuning range. Here we demonstrate reconfiguration of coupled photonic crystal nanobeam cavities by using optical gradient force induced mechanical actuation. Propagating waveguide modes that exist over a wide wavelength range are used to actuate the structures and control the resonance of localized cavity modes. Using this all-optical approach, more than 18 linewidths of tuning range is demonstrated. Using an on-chip temperature self-referencing method, we determine that 20% of the total tuning was due to optomechanical reconfiguration and the rest due to thermo-optic effects. By operating the device at frequencies higher than the thermal cutoff, we show high-speed operation dominated by just optomechanical effects. Independent control of mechanical and optical resonances of our structures is also demonstrated.

Bistability in a hybrid optomechanical system: effect of a gain medium

NASA Astrophysics Data System (ADS)

Asghari Nejad, A.; Baghshahi, H. R.; Askari, H. R.

2017-11-01

In this paper, we investigate the optical bistability of a hybrid optomechanical system consisting of two coupled cavities: a bare optomechanical cavity (with an oscillating mirror at one end) and a traditional one. The traditional cavity is filled with an optical parametric amplifier (OPA), and an input pump laser is applied to it. The Hamiltonian of the system is written in a rotating frame. The dynamics of the system is driven by the quantum Langevin equations of motion. We demonstrate that the presence of an OPA can dramatically affect the type of stability of the optomechanical cavity. We show that it is possible to create a proper optical bistability for the optomechanical cavity by changing the gain coefficient of the OPA. Also, it is shown that changing the phase of the field driving the OPA has two different effects on the bistability region of the optomechanical cavity. Moreover, we show that by choosing a proper value for the detuning of the traditional cavity it is possible to observe a tristable behavior in the optomechanical cavity.

Invariant-based inverse engineering for fluctuation transfer between membranes in an optomechanical cavity system

NASA Astrophysics Data System (ADS)

Chen, Ye-Hong; Shi, Zhi-Cheng; Song, Jie; Xia, Yan

2018-02-01

In this paper, by invariant-based inverse engineering, we design classical driving fields to transfer quantum fluctuations between two suspended membranes in an optomechanical cavity system. The transfer can be quickly attained through a nonadiabatic evolution path determined by a so-called dynamical invariant. Such an evolution path allows one to optimize the occupancies of the unstable "intermediate" states; thus, the influence of cavity decays can be suppressed. Numerical simulation demonstrates that a perfect fluctuation transfer between two membranes can be rapidly achieved in one step, and the transfer is robust to both the amplitude noises and cavity decays.

Sensitivity of optical mass sensor enhanced by optomechanical coupling

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Yong, E-mail: hey@cczu.edu.cn

Optical mass sensors based on cavity optomechanics employ radiation pressure force to drive mechanical resonator whose mechanical susceptibility can be described by nonlinear optical transmission spectrum. In this paper, we present an optical mass sensor based on a two-cavity optomechanical system where the mechanical damping rate can be decreased by adjusting a pump power so that the mass sensitivity which depends on the mechanical quality factor has been enhanced greatly. Compared with that of an optical mass sensor based on single-cavity optomechanics, the mass sensitivity of the optical mass sensor is improved by three orders of magnitude. This is anmore » approach to enhance the mass sensitivity by means of optomechanical coupling, which is suitable for all mass sensor based on cavity optomechanics. Finally, we illustrate the accurate measurement for the mass of a few chromosomes, which can be achieved based on the current experimental conditions.« less

Cavity optomechanical spring sensing of single molecules

NASA Astrophysics Data System (ADS)

Yu, Wenyan; Jiang, Wei C.; Lin, Qiang; Lu, Tao

2016-07-01

Label-free bio-sensing is a critical functionality underlying a variety of health- and security-related applications. Micro-/nano-photonic devices are well suited for this purpose and have emerged as promising platforms in recent years. Here we propose and demonstrate an approach 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 approaches, allowing us to detect single bovine serum albumin proteins with a molecular weight of 66 kDa at a signal-to-noise ratio of 16.8. The unique optical spring sensing approach opens up a distinctive avenue that not only enables biomolecule sensing and recognition at individual level, but is also of great promise for broad physical sensing applications that rely on sensitive detection of optical cavity resonance shift to probe external physical parameters.

Controllable optical bistability in a three-mode optomechanical system with atom-cavity-mirror couplings

NASA Astrophysics Data System (ADS)

Chen, Bin; Wang, Xiao-Fang; Yan, Jia-Kai; Zhu, Xiao-Fei; Jiang, Cheng

2018-01-01

We theoretically investigate the optical bistable behavior in a three-mode optomechanical system with atom-cavity-mirror couplings. The effects of the cavity-pump detuning and the pump power on the bistable behavior are discussed detailedly, the impacts of the atom-pump detuning and the atom-cavity coupling strength on the bistability of the system are also explored, and the influences of the cavity-resonator coupling strength and the cavity decay rate are also taken into consideration. The numerical results demonstrate that by tuning these parameters the bistable behavior of the system can be freely switched on or off, and the threshold of the pump power for the bistability as well as the bistable region width can also be effectively controlled. These results can find potential applications in optical bistable switch in the quantum information processing.

Si3N4 Optomechanical Crystals in the Resolved-sideband Regime

DTIC Science & Technology

2014-01-27

between cavity photons and phonons was used to demon- strate electromagnetically induced transparency ( EIT ) mediated by a mechanical resonance; radiation...wavelength range. The sideband resolution achieved was sufficient for observing, at room temperature and atmos- pheric pressure, EIT mediated by a 4 GHz...sufficient for the observation of optomechanical EIT at room tempera- ture and atmospheric pressure. This effect corresponds to the creation of a narrow

Alq3 coated silicon nanomembranes for cavity optomechanics

NASA Astrophysics Data System (ADS)

Fogliano, Francesco; Ortu, Antonio; Camposeo, Andrea; Pisignano, Dario; Ciampini, Donatella; Fuso, Francesco; Arimondo, E.

2016-09-01

The optomechanical properties of a silicon-nitride membrane mirror covered by Alq3 and Silver layers are investigated. Excitation at two laser wavelengths, 780 and 405 nm, corresponding to different absorptions of the multilayer, is examined. Such dual driving will lead to a more flexible optomechanical operation. Topographic reconstruction of the whole static membrane deformation and cooling of the membrane oscillations are reported. The cooling, observed for blue laser detuning and produced by bolometric forces, is deduced from the optomechanical damping of the membrane eigenfrequency. We determine the presence of different contributions to the photothermal response of the membrane.

Quantum theory of continuum optomechanics

NASA Astrophysics Data System (ADS)

Rakich, Peter; Marquardt, Florian

2018-04-01

We present the basic ingredients of continuum optomechanics, i.e. the suitable extension of cavity-optomechanical concepts to the interaction of photons and phonons in an extended waveguide. We introduce a real-space picture and argue which coupling terms may arise in leading order in the spatial derivatives. This picture allows us to discuss quantum noise, dissipation, and the correct boundary conditions at the waveguide entrance. The connections both to optomechanical arrays as well as to the theory of Brillouin scattering in waveguides are highlighted. Among other examples, we analyze the ‘strong coupling regime’ of continuum optomechanics that may be accessible in future experiments.

Single-photon blockade in a hybrid cavity-optomechanical system via third-order nonlinearity

NASA Astrophysics Data System (ADS)

Sarma, Bijita; Sarma, Amarendra K.

2018-04-01

Photon statistics in a weakly driven optomechanical cavity, with Kerr-type nonlinearity, are analyzed both analytically and numerically. The single-photon blockade effect is demonstrated via calculations of the zero-time-delay second-order correlation function g (2)(0). The analytical results obtained by solving the Schrödinger equation are in complete conformity with the results obtained through numerical solution of the quantum master equation. A systematic study on the parameter regime for observing photon blockade in the weak coupling regime is reported. The parameter regime where the photon blockade is not realizable due to the combined effect of nonlinearities owing to the optomechanical coupling and the Kerr-effect is demonstrated. The experimental feasibility with state-of-the-art device parameters is discussed and it is observed that photon blockade could be generated at the telecommunication wavelength. An elaborate analysis of the thermal effects on photon antibunching is presented. The system is found to be robust against pure dephasing-induced decoherences and thermal phonon number fluctuations.

Controlling the opto-mechanics of a cantilever in an interferometer via cavity loss

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidsfeld, A. von, E-mail: avonschm@uos.de; Reichling, M., E-mail: reichling@uos.de

2015-09-21

In a non-contact atomic force microscope, based on interferometric cantilever displacement detection, the optical return loss of the system is tunable via the distance between the fiber end and the cantilever. We utilize this for tuning the interferometer from a predominant Michelson to a predominant Fabry-Pérot characteristics and introduce the Fabry-Pérot enhancement factor as a quantitative measure for multibeam interference in the cavity. This experimentally easily accessible and adjustable parameter provides a control of the opto-mechanical interaction between the cavity light field and the cantilever. The quantitative assessment of the light pressure acting on the cantilever oscillating in the cavitymore » via the frequency shift allows an in-situ measurement of the cantilever stiffness with remarkable precision.« less

Fabrication and Testing of Microfluidic Optomechanical Oscillators

PubMed Central

Han, Kewen; Kim, Kyu Hyun; Kim, Junhwan; Lee, Wonsuk; Liu, Jing; Fan, Xudong; Carmon, Tal; Bahl, Gaurav

2014-01-01

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including microresonators. However, because of the increased acoustic radiative losses during direct liquid immersion of optomechanical devices, almost all published optomechanical experiments have been performed in solid phase. This paper discusses a recently introduced hollow microfluidic optomechanical resonator. Detailed methodology is provided to fabricate these ultra-high-Q microfluidic resonators, perform optomechanical testing, and measure radiation pressure-driven breathing mode and SBS-driven whispering gallery mode parametric vibrations. By confining liquids inside the capillary resonator, high mechanical- and optical- quality factors are simultaneously maintained. PMID:24962013

Effects of quadratic coupling and squeezed vacuum injection in an optomechanical cavity assisted with a Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Dalafi, A.; Naderi, M. H.; Motazedifard, Ali

2018-04-01

We investigate theoretically a hybrid system consisting of a Bose-Einstein condensate (BEC) trapped inside a laser-driven membrane-in-the-middle optomechanical cavity assisted with squeezed vacuum injection whose moving membrane interacts both linearly and quadratically with the radiation pressure of the cavity. It is shown that such a hybrid system is very suitable for generating strong quadrature squeezing in the mechanical mode of the membrane and the Bogoliubov mode of the BEC in the unresolved sideband regime. More interestingly, by choosing a suitable sign for the quadratic optomechanical coupling (QOC), one can achieve a very high degree of squeezing in the mechanical mode and a strong entanglement between the mechanical and atomic modes without the necessity of using squeezed light injection. Furthermore, the QOC changes the effective oscillation frequencies of both the mechanical and the atomic modes and affects their relaxation times. It can also make the system switch from optical bistability to tristability.

Optomechanical entanglement via non-degenerate parametric interactions

NASA Astrophysics Data System (ADS)

Ahmed, Rizwan; Qamar, Shahid

2017-10-01

We present a scheme for the optomechanical entanglement between a micro-mechanical mirror and the field inside a bimodal cavity system using a non-degenerate optical parametric amplifier (NOPA). Our results show that the introduction of NOPA makes the entanglement stronger or more robust against the mean number of average thermal phonons and cavity decay. Interestingly, macroscopic entanglement depends upon the choice of the phase associated with classical field driving NOPA. We also consider the effects of input laser power on optomechanical entanglement.

Optical tristability in a hybrid optomechanical system

NASA Astrophysics Data System (ADS)

Asghari Nejad, A.; Askari, H. R.; Baghshahi, H. R.

2018-05-01

In this paper, we investigate a hybrid optomechanical system consisting of two cavities, which one of them is an optomechanical cavity that includes an optical parametric amplifier (OPA) and the other is a traditional cavity which contains an atomic medium. Hamiltonian of the system is written in a rotating frame with a rotation frequency of the frequency of input field to the system. Using Heisenberg-Langevin equations of motion, the dynamics of the system is described. Applying the steady-state conditions leads to a system of equations of the mean values of the operators of the system. The stability condition of the system is satisfied numerically and behavior of optomechanical cavity is investigated in different situations to find the effect of changing of the parameters of the system on the type of its stability. We show proposed system has the capability of tristable behavior, where, the gain coefficient of OPA acts as a switch in changing the bistability of the system to a tristable manner. The building block of the tristability in this system can be figured out as the enhanced nonlinearity of the system due to the presence of OPA.

A dissipative self-sustained optomechanical resonator on a silicon chip

NASA Astrophysics Data System (ADS)

Huang, J. G.; Li, Y.; Chin, L. K.; Cai, H.; Gu, Y. D.; Karim, M. F.; Wu, J. H.; Chen, T. N.; Yang, Z. C.; Hao, Y. L.; Qiu, C. W.; Liu, A. Q.

2018-01-01

In this letter, we report the experimental demonstration of a dissipative self-sustained optomechanical resonator on a silicon chip by introducing dissipative optomechanical coupling between a vertically offset bus waveguide and a racetrack optical cavity. Different from conventional blue-detuning limited self-oscillation, the dissipative optomechanical resonator exhibits self-oscillation in the resonance and red detuning regime. The anti-damping effects of dissipative optomechanical coupling are validated by both numerical simulation and experimental results. The demonstration of the dissipative self-sustained optomechanical resonator with an extended working range has potential applications in optomechanical oscillation for on-chip signal modulation and processing.

Steady-state entanglement in levitated optomechanical systems coupled to a higher order excited atomic ensemble

NASA Astrophysics Data System (ADS)

Chen, Aixi; Nie, Wenjie; Li, Ling; Zeng, Wei; Liao, Qinghong; Xiao, Xianbo

2017-11-01

We investigate the steady-state entanglement in an optomechanical system with a levitated dielectric nanosphere and a higher order excited atomic ensemble. The single nanosphere is trapped by an external harmonic dipole trap and coupled to the single-mode cavity field by the effective optomechanical coupling, which depends on the steady-state position of the nanosphere. We show that the steady-state optomechanical entanglement can be generated via the effective optomechanical interaction between the mechanical motion and the cavity mode. Further, these exist an optimal effective cavity detuning that maximizes the optomechanical entanglement. We also analyze in detail the influences of the excitation number of atoms, the radius of the nanosphere and the thermal noise strength on the steady-state optomechanical entanglement. It is found that the steady-state entanglement can be enhanced by increasing the excitation number of atoms and the radius of the nanosphere.

Parity-time-symmetry enhanced optomechanically-induced-transparency

PubMed Central

Li, Wenlin; Jiang, Yunfeng; Li, Chong; Song, Heshan

2016-01-01

We propose and analyze a scheme to enhance optomechanically-induced-transparency (OMIT) based on parity-time-symmetric optomechanical system. Our results predict that an OMIT window which does not exist originally can appear in weak optomechanical coupling and driving system via coupling an auxiliary active cavity with optical gain. This phenomenon is quite different from these reported in previous works in which the gain is considered just to damage OMIT phenomenon even leads to electromagnetically induced absorption or inverted-OMIT. Such enhanced OMIT effects are ascribed to the additional gain which can increase photon number in cavity without reducing effective decay. We also discuss the scheme feasibility by analyzing recent experiment parameters. Our work provide a promising platform for the coherent manipulation and slow light operation, which has potential applications for quantum information processing and quantum optical device. PMID:27489193

Optomechanical frequency combs

NASA Astrophysics Data System (ADS)

Miri, Mohammad-Ali; D’Aguanno, Giuseppe; Alù, Andrea

2018-04-01

We study the formation of frequency combs in a single-mode optomechanical cavity. The comb is composed of equidistant spectral lines centered at the pump laser frequency and located at different harmonics of the mechanical resonator. We investigate the classical nonlinear dynamics of such system and find analytically the onset of parametric instability resulting in the breakdown of a stationary continuous wave intracavity field into a periodic train of pulses, which in the Fourier domain gives rise to a broadband frequency comb. Different dynamical regimes, including a stationary state, frequency comb generation and chaos, and their dependence on the system parameters, are studied both analytically and numerically. Interestingly, the comb generation is found to be more robust in the poor cavity limit, where optical loss is equal or larger than the mechanical resonance frequency. Our results show that optomechanical resonators open exciting opportunities for microwave photonics as compact and robust sources of frequency combs with megahertz line spacing.

Tunable Bistability in Hybrid Bose-Einstein Condensate Optomechanics

PubMed Central

Yasir, Kashif Ammar; Liu, Wu-Ming

2015-01-01

Cavity-optomechanics, a rapidly developing area of research, has made a remarkable progress. A stunning manifestation of optomechanical phenomena is in exploiting the mechanical effects of light to couple the optical degree of freedom with mechanical degree of freedom. In this report, we investigate the controlled bistable dynamics of such hybrid optomechanical system composed of cigar-shaped Bose-Einstein condensate (BEC) trapped inside high-finesse optical cavity with one moving-end mirror and is driven by a single mode optical field. The numerical results provide evidence for controlled optical bistability in optomechanics using transverse optical field which directly interacts with atoms causing the coupling of transverse field with momentum side modes, exited by intra-cavity field. This technique of transverse field coupling is also used to control bistable dynamics of both moving-end mirror and BEC. The report provides an understanding of temporal dynamics of moving-end mirror and BEC with respect to transverse field. Moreover, dependence of effective potential of the system on transverse field has also been discussed. To observe this phenomena in laboratory, we have suggested a certain set of experimental parameters. These findings provide a platform to investigate the tunable behavior of novel phenomenon like electromagnetically induced transparency and entanglement in hybrid systems. PMID:26035206

Optomechanical transistor with mechanical gain

NASA Astrophysics Data System (ADS)

Zhang, X. Z.; Tian, Lin; Li, Yong

2018-04-01

We study an optomechanical transistor, where an input field can be transferred and amplified unidirectionally in a cyclic three-mode optomechanical system. In this system, the mechanical resonator is coupled simultaneously to two cavity modes. We show that it only requires a finite mechanical gain to achieve the nonreciprocal amplification. Here the nonreciprocity is caused by the phase difference between the linearized optomechanical couplings that breaks the time-reversal symmetry of this system. The amplification arises from the mechanical gain, which provides an effective phonon bath that pumps the mechanical mode coherently. This effect is analogous to the stimulated emission of atoms, where the probe field can be amplified when its frequency is in resonance with that of the anti-Stokes transition. We show that by choosing optimal parameters, this optomechanical transistor can reach perfect unidirectionality accompanied with strong amplification. In addition, the presence of the mechanical gain can result in ultralong delay in the phase of the probe field, which provides an alternative to controlling light transport in optomechanical systems.

Cavity optomechanics in a levitated helium drop

NASA Astrophysics Data System (ADS)

Childress, L.; Schmidt, M. P.; Kashkanova, A. D.; Brown, C. D.; Harris, G. I.; Aiello, A.; Marquardt, F.; Harris, J. G. E.

2017-12-01

We describe a proposal for a type of optomechanical system based on a drop of liquid helium that is magnetically levitated in vacuum. In the proposed device, the drop would serve three roles: its optical whispering-gallery modes would provide the optical cavity, its surface vibrations would constitute the mechanical element, and evaporation of He atoms from its surface would provide continuous refrigeration. We analyze the feasibility of such a system in light of previous experimental demonstrations of its essential components: magnetic levitation of mm-scale and cm-scale drops of liquid He , evaporative cooling of He droplets in vacuum, and coupling to high-quality optical whispering-gallery modes in a wide range of liquids. We find that the combination of these features could result in a device that approaches the single-photon strong-coupling regime, due to the high optical quality factors attainable at low temperatures. Moreover, the system offers a unique opportunity to use optical techniques to study the motion of a superfluid that is freely levitating in vacuum (in the case of 4He). Alternatively, for a normal fluid drop of 3He, we propose to exploit the coupling between the drop's rotations and vibrations to perform quantum nondemolition measurements of angular momentum.

Optomechanically induced spontaneous symmetry breaking

NASA Astrophysics Data System (ADS)

Miri, Mohammad-Ali; Verhagen, Ewold; Alú, Andrea

2017-05-01

We explore the dynamics of spontaneous breakdown of mirror symmetry in a pair of identical optomechanical cavities symmetrically coupled to a waveguide. Large optical intensities enable optomechanically induced nonlinear detuning of the optical resonators, resulting in a pitchfork bifurcation. We investigate the stability of this regime and explore the possibility of inducing multistability. By injecting proper trigger pulses, the proposed structure can toggle between two asymmetric stable states, thus serving as a low-noise nanophotonic all-optical switch or memory element.

All-optical transistor based on Rydberg atom-assisted optomechanical system.

PubMed

Liu, Yi-Mou; Tian, Xue-Dong; Wang, Jing; Fan, Chu-Hui; Gao, Feng; Bao, Qian-Qian

2018-04-30

We study the optical response of a double optomechanical cavity system assisted by two Rydberg atoms. The target atom is only coupled with one side cavity by a single cavity mode, and gate one is outside the cavities. It has been realized that a long-range manipulation of optical properties of a hybrid system, by controlling the Rydberg atom decoupled with the optomechanical cavity. Switching on the coupling between atoms and cavity mode, the original spatial inversion symmetry of the double cavity structure has been broken. Combining the controllable optical non-reciprocity with the coherent perfect absorption/transmission/synthesis effect (CPA/CPT/CPS reported by [ X.-B.Yan Opt. Express 22, 4886 (2014)], we put forward the theoretical schemes of an all-optical transistor which contains functions such as a controllable diode, rectifier, and amplifier by controlling a single gate photon.

Brillouin Optomechanics in Coupled Silicon Microcavities

NASA Astrophysics Data System (ADS)

Espinel, Y. A. V.; Santos, F. G. S.; Luiz, G. O.; Alegre, T. P. Mayer; Wiederhecker, G. S.

2017-03-01

The simultaneous control of optical and mechanical waves has enabled a range of fundamental and technological breakthroughs, from the demonstration of ultra-stable frequency reference devices, to the exploration of the quantum-classical boundaries in optomechanical laser-cooling experiments. More recently, such an optomechanical interaction has been observed in integrated nano-waveguides and microcavities in the Brillouin regime, where short-wavelength mechanical modes scatter light at several GHz. Here we engineer coupled optical microcavities to enable a low threshold excitation of mechanical travelling-wave modes through backward stimulated Brillouin scattering. Exploring the backward scattering we propose silicon microcavity designs based on laterally coupled single and double-layer cavities, the proposed structures enable optomechanical coupling with very high frequency modes (11 to 25 GHz) and large optomechanical coupling rates (g0/2π) from 50 kHz to 90 kHz.

Wigner Function Reconstruction in Levitated Optomechanics

NASA Astrophysics Data System (ADS)

Rashid, Muddassar; Toroš, Marko; Ulbricht, Hendrik

2017-10-01

We demonstrate the reconstruction of theWigner function from marginal distributions of the motion of a single trapped particle using homodyne detection. We show that it is possible to generate quantum states of levitated optomechanical systems even under the efect of continuous measurement by the trapping laser light. We describe the opto-mechanical coupling for the case of the particle trapped by a free-space focused laser beam, explicitly for the case without an optical cavity. We use the scheme to reconstruct the Wigner function of experimental data in perfect agreement with the expected Gaussian distribution of a thermal state of motion. This opens a route for quantum state preparation in levitated optomechanics.

Optomechanics of two- and three-dimensional soft photonic crystals

NASA Astrophysics Data System (ADS)

Krishnan, Dwarak

Soft photonic crystals are a class of periodic dielectric structures that undergo highly nonlinear deformation due to strain or other external stimulus such as temperature, pH etc. This can in turn dramatically affect optical properties such as light transmittance. Moreover certain classes of lithographically fabricated structures undergo some structural distortion due to the effects of processing, eventually affecting the optical properties of the final photonic crystal. In this work, we study the deformation mechanics of soft photonic crystal structures using realistic physics-based models and leverage that understanding to explain the optomechanics of actual 2-D and 3-D soft photonic crystals undergoing similar symmetry breaking nonlinear deformations. We first study the optomechanics of two classes of 3-D soft photonic crystals: (1) hydrogel and (2) elastomer based material systems. The hydrogel based inverse face-centered-cubic structure undergoes swelling with change in pH of the surrounding fluid. The inverse structure is a network of bulky domains with thin ligament-like connections, and it undergoes a pattern transformation from FCC to L11 as a result of swelling. A continuum scale poroelasticity based coupled fluid-diffusion FEM model is developed to accurately predict this mechanical behavior. Light transmittance simulation results qualitatively explain the experimentally observed trends in the optical behavior with pH change. The elastomer based, lithographically fabricated material experiences shrinkage induced distortion upon processing. This behavior is modeled using FEM with the material represented by a neo-Hookean constitutive law. The light transmittance calculations for normal incidence are carried out using the transfer matrix method and a good comparison is obtained for the positions of first and second order reflectance peaks. A unit cell based approach is taken to compute the photonic bandstructure to estimate light propagation through the

Directional amplifier in an optomechanical system with optical gain

NASA Astrophysics Data System (ADS)

Jiang, Cheng; Song, L. N.; Li, Yong

2018-05-01

Directional amplifiers are crucial nonreciprocal devices in both classical and quantum information processing. Here we propose a scheme for realizing a directional amplifier between optical and microwave fields based on an optomechanical system with optical gain, where an active optical cavity and two passive microwave cavities are coupled to a common mechanical resonator via radiation pressure. The two passive cavities are coupled via hopping interaction to facilitate the directional amplification between the active and passive cavities. We obtain the condition of achieving optical directional amplification and find that the direction of amplification can be controlled by the phase differences between the effective optomechanical couplings. The effects of the gain rate of the active cavity and the effective coupling strengths on the maximum gain of the amplifier are discussed. We show that the noise added to this amplifier can be greatly suppressed in the large cooperativity limit.

Effective Hamiltonian approach to the Kerr nonlinearity in an optomechanical system

NASA Astrophysics Data System (ADS)

Gong, Z. R.; Ian, H.; Liu, Yu-Xi; Sun, C. P.; Nori, Franco

2009-12-01

Using the Born-Oppenheimer approximation, we derive an effective Hamiltonian for an optomechanical system that leads to a nonlinear Kerr effect in the system’s vacuum. The oscillating mirror at one edge of the optomechanical system induces a squeezing effect in the intensity spectrum of the cavity field. A near-resonant laser field is applied at the other edge to drive the cavity field in order to enhance the Kerr effect. We also propose a quantum-nondemolition-measurement setup to monitor a system with two cavities separated by a common oscillating mirror based on our effective Hamiltonian approach.

Thermal noise and optomechanical features in the emission of a membrane-coupled compound cavity laser diode.

PubMed

Baldacci, Lorenzo; Pitanti, Alessandro; Masini, Luca; Arcangeli, Andrea; Colangelo, Francesco; Navarro-Urrios, Daniel; Tredicucci, Alessandro

2016-08-19

We demonstrate the use of a compound optical cavity as linear displacement detector, by measuring the thermal motion of a silicon nitride suspended membrane acting as the external mirror of a near-infrared Littrow laser diode. Fluctuations in the laser optical power induced by the membrane vibrations are collected by a photodiode integrated within the laser, and then measured with a spectrum analyzer. The dynamics of the membrane driven by a piezoelectric actuator is investigated as a function of air pressure and actuator displacement in a homodyne configuration. The high Q-factor (~3.4 · 10(4) at 8.3 · 10(-3) mbar) of the fundamental mechanical mode at ~73 kHz guarantees a detection sensitivity high enough for direct measurement of thermal motion at room temperature (~87 pm RMS). The compound cavity system here introduced can be employed as a table-top, cost-effective linear displacement detector for cavity optomechanics. Furthermore, thanks to the strong optical nonlinearities of the laser compound cavity, these systems open new perspectives in the study of non-Markovian quantum properties at the mesoscale.

Thermal noise and optomechanical features in the emission of a membrane-coupled compound cavity laser diode

PubMed Central

Baldacci, Lorenzo; Pitanti, Alessandro; Masini, Luca; Arcangeli, Andrea; Colangelo, Francesco; Navarro-Urrios, Daniel; Tredicucci, Alessandro

2016-01-01

We demonstrate the use of a compound optical cavity as linear displacement detector, by measuring the thermal motion of a silicon nitride suspended membrane acting as the external mirror of a near-infrared Littrow laser diode. Fluctuations in the laser optical power induced by the membrane vibrations are collected by a photodiode integrated within the laser, and then measured with a spectrum analyzer. The dynamics of the membrane driven by a piezoelectric actuator is investigated as a function of air pressure and actuator displacement in a homodyne configuration. The high Q-factor (~3.4 · 104 at 8.3 · 10−3 mbar) of the fundamental mechanical mode at ~73 kHz guarantees a detection sensitivity high enough for direct measurement of thermal motion at room temperature (~87 pm RMS). The compound cavity system here introduced can be employed as a table-top, cost-effective linear displacement detector for cavity optomechanics. Furthermore, thanks to the strong optical nonlinearities of the laser compound cavity, these systems open new perspectives in the study of non-Markovian quantum properties at the mesoscale. PMID:27538586

Enhanced nonlinear interactions in quantum optomechanics via mechanical amplification

PubMed Central

Lemonde, Marc-Antoine; Didier, Nicolas; Clerk, Aashish A.

2016-01-01

The quantum nonlinear regime of optomechanics is reached when nonlinear effects of the radiation pressure interaction are observed at the single-photon level. This requires couplings larger than the mechanical frequency and cavity-damping rate, and is difficult to achieve experimentally. Here we show how to exponentially enhance the single-photon optomechanical coupling strength using only additional linear resources. Our method is based on using a large-amplitude, strongly detuned mechanical parametric drive to amplify mechanical zero-point fluctuations and hence enhance the radiation pressure interaction. It has the further benefit of allowing time-dependent control, enabling pulsed schemes. For a two-cavity optomechanical set-up, we show that our scheme generates photon blockade for experimentally accessible parameters, and even makes the production of photonic states with negative Wigner functions possible. We discuss how our method is an example of a more general strategy for enhancing boson-mediated two-particle interactions and nonlinearities. PMID:27108814

Ultralow-Noise SiN Trampoline Resonators for Sensing and Optomechanics

NASA Astrophysics Data System (ADS)

Reinhardt, Christoph; Müller, Tina; Bourassa, Alexandre; Sankey, Jack C.

2016-04-01

In force sensing, optomechanics, and quantum motion experiments, it is typically advantageous to create lightweight, compliant mechanical elements with the lowest possible force noise. Here, we report the fabrication and characterization of high-aspect-ratio, nanogram-scale Si3 N4 "trampolines" having quality factors above 4 ×107 and ringdown times exceeding 5 min (mHz linewidth). These devices exhibit thermally limited force noise sensitivities below 20 aN /Hz1 /2 at room temperature, which is the lowest among solid-state mechanical sensors. We also characterize the suitability of these devices for high-finesse cavity readout and optomechanics applications, finding no evidence of surface or bulk optical losses from the processed nitride in a cavity achieving finesse 40,000. These parameters provide access to a single-photon cooperativity C0˜8 in the resolved-sideband limit, wherein a variety of outstanding optomechanics goals become feasible.

A low-frequency chip-scale optomechanical oscillator with 58 kHz mechanical stiffening and more than 100th-order stable harmonics.

PubMed

Huang, Yongjun; Flores, Jaime Gonzalo Flor; Cai, Ziqiang; Yu, Mingbin; Kwong, Dim-Lee; Wen, Guangjun; Churchill, Layne; Wong, Chee Wei

2017-06-29

For the sensitive high-resolution force- and field-sensing applications, the large-mass microelectromechanical system (MEMS) and optomechanical cavity have been proposed to realize the sub-aN/Hz 1/2 resolution levels. In view of the optomechanical cavity-based force- and field-sensors, the optomechanical coupling is the key parameter for achieving high sensitivity and resolution. Here we demonstrate a chip-scale optomechanical cavity with large mass which operates at ≈77.7 kHz fundamental mode and intrinsically exhibiting large optomechanical coupling of 44 GHz/nm or more, for both optical resonance modes. The mechanical stiffening range of ≈58 kHz and a more than 100 th -order harmonics are obtained, with which the free-running frequency instability is lower than 10 -6 at 100 ms integration time. Such results can be applied to further improve the sensing performance of the optomechanical inspired chip-scale sensors.

Steady-State Solutions Originating from an Enhanced Nonlinear Feedback in a Hybrid Opto-mechanical System

NASA Astrophysics Data System (ADS)

Fan, Qiu-Bo; Wang, Yi-Ru; Chen, Jin; Pan, Yue-Wu; Han, Bai-Ping; Fu, Chang-Bao; Sun, Yan

2017-06-01

The steady-state properties of a hybrid system are investigated in this paper. Many cold atoms in the four-level tripod configuration are confined in an optical cavity with a movable end mirror. The confined cold atoms are driven with two external classical fields and an internal cavity field. The internal cavity field is excited by an external driving field and shows a radiation pressure upon the movable end mirror. The coupling of atom-light and opto-mechanical interactions is enhanced by embedding a four-level atomic system in a typical opto-mechanical cavity. And an enhanced nonlinear feedback mechanism is offered by the enhanced coupling, which permits the observation of five and three steady-state solutions for relevant variables near two-photon resonance. The enhanced nonlinear feedback mechanism also allows us to observe the obvious difference in the double-EIT phenomenon between the atom-assisted opto-mechanical system and usual atom-field system.

Towards thermal noise free optomechanics

NASA Astrophysics Data System (ADS)

Page, Michael A.; Zhao, Chunnong; Blair, David G.; Ju, Li; Ma, Yiqiu; Pan, Huang-Wei; Chao, Shiuh; Mitrofanov, Valery P.; Sadeghian, Hamed

2016-11-01

Thermal noise generally greatly exceeds quantum noise in optomechanical devices unless the mechanical frequency is very high or the thermodynamic temperature is very low. This paper addresses the design concept for a novel optomechanical device capable of ultrahigh quality factors in the audio frequency band with negligible thermal noise. The proposed system consists of a minimally supported millimeter scale pendulum mounted in a double end-mirror sloshing cavity that is topologically equivalent to a membrane-in-the-middle cavity. The radiation pressure inside the high-finesse cavity allows for high optical stiffness, cancellation of terms which lead to unwanted negative damping and suppression of quantum radiation pressure noise. We solve the optical spring dynamics of the system using the Hamiltonian, find the noise spectral density and show that stable optical trapping is possible. We also assess various loss mechanisms, one of the most important being the acceleration loss due to the optical spring. We show that practical devices, starting from a centre-of-mass pendulum frequency of 0.1 Hz, could achieve a maximum quality factor of (1014) with optical spring stiffened frequency 1-10 kHz. Small resonators of mass 1 ≤ft(μ \\right) g or less could achieve a Q-factor of (1011) at a frequency of 100 kHz. Applications for such devices include white light cavities for improvement of gravitational wave detectors, or sensors able to operate near the quantum limit.

Cavity magnomechanics

PubMed Central

Zhang, Xufeng; Zou, Chang-Ling; Jiang, Liang; Tang, Hong X.

2016-01-01

A dielectric body couples with electromagnetic fields through radiation pressure and electrostrictive forces, which mediate phonon-photon coupling in cavity optomechanics. In a magnetic medium, according to the Korteweg-Helmholtz formula, which describes the electromagnetic force density acting on a medium, magneostrictive forces should arise and lead to phonon-magnon interaction. We report such a coupled phonon-magnon system based on ferrimagnetic spheres, which we term as cavity magnomechanics, by analogy to cavity optomechanics. Coherent phonon-magnon interactions, including electromagnetically induced transparency and absorption, are demonstrated. Because of the strong hybridization of magnon and microwave photon modes and their high tunability, our platform exhibits new features including parametric amplification of magnons and phonons, triple-resonant photon-magnon-phonon coupling, and phonon lasing. Our work demonstrates the fundamental principle of cavity magnomechanics and its application as a new information transduction platform based on coherent coupling between photons, phonons, and magnons. PMID:27034983

Generalized non-reciprocity in an optomechanical circuit via synthetic magnetism and reservoir engineering

NASA Astrophysics Data System (ADS)

Fang, Kejie; Luo, Jie; Metelmann, Anja; Matheny, Matthew H.; Marquardt, Florian; Clerk, Aashish A.; Painter, Oskar

2017-01-01

Synthetic magnetism has been used to control charge neutral excitations for applications ranging from classical beam steering to quantum simulation. In optomechanics, radiation-pressure-induced parametric coupling between optical (photon) and mechanical (phonon) excitations may be used to break time-reversal symmetry, providing the prerequisite for synthetic magnetism. Here we design and fabricate a silicon optomechanical circuit with both optical and mechanical connectivity between two optomechanical cavities. Driving the two cavities with phase-correlated laser light results in a synthetic magnetic flux, which, in combination with dissipative coupling to the mechanical bath, leads to non-reciprocal transport of photons with 35 dB of isolation. Additionally, optical pumping with blue-detuned light manifests as a particle non-conserving interaction between photons and phonons, resulting in directional optical amplification of 12 dB in the isolator through-direction. These results suggest the possibility of using optomechanical circuits to create a more general class of non-reciprocal optical devices, and further, to enable new topological phases for both light and sound on a microchip.

Optomechanical proposal for monitoring microtubule mechanical vibrations

NASA Astrophysics Data System (ADS)

Barzanjeh, Sh.; Salari, V.; Tuszynski, J. A.; Cifra, M.; Simon, C.

2017-07-01

Microtubules provide the mechanical force required for chromosome separation during mitosis. However, little is known about the dynamic (high-frequency) mechanical properties of microtubules. Here, we theoretically propose to control the vibrations of a doubly clamped microtubule by tip electrodes and to detect its motion via the optomechanical coupling between the vibrational modes of the microtubule and an optical cavity. In the presence of a red-detuned strong pump laser, this coupling leads to optomechanical-induced transparency of an optical probe field, which can be detected with state-of-the art technology. The center frequency and line width of the transparency peak give the resonance frequency and damping rate of the microtubule, respectively, while the height of the peak reveals information about the microtubule-cavity field coupling. Our method opens the new possibilities to gain information about the physical properties of microtubules, which will enhance our capability to design physical cancer treatment protocols as alternatives to chemotherapeutic drugs.

Controllable nonlinearity in a dual-coupling optomechanical system under a weak-coupling regime

NASA Astrophysics Data System (ADS)

Zhu, Gui-Lei; Lü, Xin-You; Wan, Liang-Liang; Yin, Tai-Shuang; Bin, Qian; Wu, Ying

2018-03-01

Strong quantum nonlinearity gives rise to many interesting quantum effects and has wide applications in quantum physics. Here we investigate the quantum nonlinear effect of an optomechanical system (OMS) consisting of both linear and quadratic coupling. Interestingly, a controllable optomechanical nonlinearity is obtained by applying a driving laser into the cavity. This controllable optomechanical nonlinearity can be enhanced into a strong coupling regime, even if the system is initially in the weak-coupling regime. Moreover, the system dissipation can be suppressed effectively, which allows the appearance of phonon sideband and photon blockade effects in the weak-coupling regime. This work may inspire the exploration of a dual-coupling optomechanical system as well as its applications in modern quantum science.

Optical response of two coupled optomechanical systems in the presence of nonlinear mediums

NASA Astrophysics Data System (ADS)

Asghari Nejad, A.; Askari, H. R.; Baghshahi, H. R.

2018-01-01

In this paper, we investigate response of a hybrid optomechanical system in different situations. This system is composed of two coupled optomechanical cavities, which one of them is filled with an optical parametric amplifier (OPA) and the other one encompasses a nonlinear Kerr medium. The Hamiltonian of the system is written in a rotating frame. The dynamics of the system is obtained by the quantum Langevin equations of motion in a steady state regime. The results show that the presence of OPA and the Kerr medium in the system can considerably change the behavior of both cavities. For this reason, we show that by choosing different values for the optical parameters of the system, one can switches the behaviors of the cavities between mono-, bi- and tristability. Also, we show that by changing the detunings of the cavities, one can obtain uncommon responses from the system. Furthermore, we show that it is possible to create proper optical multistability regions for both cavities.

Nonreciprocal reconfigurable microwave optomechanical circuit.

PubMed

Bernier, N R; Tóth, L D; Koottandavida, A; Ioannou, M A; Malz, D; Nunnenkamp, A; Feofanov, A K; Kippenberg, T J

2017-09-19

Nonreciprocal microwave devices are ubiquitous in radar and radio communication and indispensable in the readout chains of superconducting quantum circuits. Since they commonly rely on ferrite materials requiring large magnetic fields that make them bulky and lossy, there has been significant interest in magnetic-field-free on-chip alternatives, such as those recently implemented using the Josephson nonlinearity. Here, we realize reconfigurable nonreciprocal transmission between two microwave modes using purely optomechanical interactions in a superconducting electromechanical circuit. The scheme relies on the interference in two mechanical modes that mediate coupling between the microwave cavities and requires no magnetic field. We analyse the isolation, transmission and the noise properties of this nonreciprocal circuit. Finally, we show how quantum-limited circulators can be realized with the same principle. All-optomechanically mediated nonreciprocity demonstrated here can also be extended to directional amplifiers, and it forms the basis towards realizing topological states of light and sound.Nonreciprocal optical devices traditionally rely on magnetic fields and magnetic-free approaches are rather recent. Here, Bernier et al. propose and demonstrate a purely optomechanical circulator with reconfigurable transmission without the need for direct coupling between input and output modes.

Multimode four-wave mixing in an unresolved sideband optomechanical system

NASA Astrophysics Data System (ADS)

Li, Zongyang; You, Xiang; Li, Yongmin; Liu, Yong-Chun; Peng, Kunchi

2018-03-01

We have studied multimode four-wave mixing (FWM) in an unresolved sideband cavity optomechanical system. The radiation pressure coupling between the cavity fields and multiple mechanical modes results in the formation of a series of tripod-type energy-level systems, which induce the multimode FWM phenomenon. The FWM mechanism enables remarkable amplification of a weak signal field accompanied by the generation of an FWM field when only a microwatt-level pump field is applied. For proper system parameters, the amplified signal and FWM fields have equal intensity with opposite phases. The gain and frequency response bandwidth of the signal field can be dynamically tuned by varying the pump intensity, optomechanical coupling strength, and additional feedback control. Under certain conditions, the frequency response bandwidth can be very narrow and reaches the level of hertz.

Polarization nondegenerate fiber Fabry-Perot cavities with large tunable splittings

NASA Astrophysics Data System (ADS)

Cui, Jin-Ming; Zhou, Kun; Zhao, Ming-Shu; Ai, Ming-Zhong; Hu, Chang-Kang; Li, Qiang; Liu, Bi-Heng; Peng, Jin-Lan; Huang, Yun-Feng; Li, Chuan-Feng; Guo, Guang-Can

2018-04-01

We demonstrate a type of microcavity with large tunable splitting of polarization modes. This polarization nondegenerate cavity consists of two ellipsoidal concave mirrors with controllable eccentricity by CO2 laser machining on fiber end facets. The experiment shows that the cavities can combine the advantages of high finesse above 104 and large tunable polarization mode splitting to the GHz range. As the splitting of the cavity can be finely controlled to match atom hyperfine levels or optomechanics phonons, it will blaze a way in experiments on cavity quantum electrodynamics and cavity optomechanics.

Single-molecule optomechanics in "picocavities".

PubMed

Benz, Felix; Schmidt, Mikolaj K; Dreismann, Alexander; Chikkaraddy, Rohit; Zhang, Yao; Demetriadou, Angela; Carnegie, Cloudy; Ohadi, Hamid; de Nijs, Bart; Esteban, Ruben; Aizpurua, Javier; Baumberg, Jeremy J

2016-11-11

Trapping light with noble metal nanostructures overcomes the diffraction limit and can confine light to volumes typically on the order of 30 cubic nanometers. We found that individual atomic features inside the gap of a plasmonic nanoassembly can localize light to volumes well below 1 cubic nanometer ("picocavities"), enabling optical experiments on the atomic scale. These atomic features are dynamically formed and disassembled by laser irradiation. Although unstable at room temperature, picocavities can be stabilized at cryogenic temperatures, allowing single atomic cavities to be probed for many minutes. Unlike traditional optomechanical resonators, such extreme optical confinement yields a factor of 10 6 enhancement of optomechanical coupling between the picocavity field and vibrations of individual molecular bonds. This work sets the basis for developing nanoscale nonlinear quantum optics on the single-molecule level. Copyright © 2016, American Association for the Advancement of Science.

Building mechanical Greenberger-Horne-Zeilinger and cluster states by harnessing optomechanical quantum steerable correlations

NASA Astrophysics Data System (ADS)

Tan, Huatang; Wei, Yanghua; Li, Gaoxiang

2017-11-01

Greenberger-Horne-Zeilinger (GHZ) and cluster states are two typical kinds of multipartite entangled states and can respectively be used for realizing quantum networks and one-way computation. We propose a feasible scheme for generating Gaussian GHZ and cluster states of multiple mechanical oscillators by pulsed cavity optomechanics. In our scheme, each optomechanical cavity is driven by a blue-detuned pulse to establish quantum steerable correlations between the cavity output field and the mechanical oscillator, and the cavity outputs are combined at a beam-splitter array with given transmissivity and reflectivity for each beam splitter. We show that by harnessing the light-mechanical steerable correlations, the mechanical GHZ and cluster states can be realized via homodyne detection on the amplitude and phase quadratures of the output fields from the beam-splitter array. These achieved mechanical entangled states can be viewed as the output states of an effective mechanical beam-splitter array with the mechanical inputs prepared in squeezed states with the light-mechanical steering. The effects of detection efficiency and thermal noise on the achieved mechanical states are investigated. The present scheme does not require externally injected squeezing and it can also be applicable to other systems such as light-atomic-ensemble interface, apart from optomechanical systems.

Dissipative versus dispersive coupling in quantum optomechanics: Squeezing ability and stability

NASA Astrophysics Data System (ADS)

Tagantsev, A. K.; Sokolov, I. V.; Polzik, E. S.

2018-06-01

The generation of squeezed light and the optomechanical instability of a dissipative type of opto-mechanical coupling are theoretically addressed for a cavity with the input mirror serving as a mechanical oscillator or for an equivalent system. The problem is treated analytically for the case of resonance excitation or small detunings, mainly focusing on the bad-cavity limit. A qualitative difference between the dissipative and purely dispersive coupling is reported. In particular, it is shown that, for the purely dissipative coupling in the bad-cavity regime, the backaction is strongly reduced and the squeezing ability of the system is strongly suppressed, in contrast to the case of purely dispersive coupling. It is also shown that, for small detunings, stability diagrams for the cases of the purely dispersive and dissipative couplings are qualitatively identical to within the change of the sign of detuning. The results obtained are compared with those from the recent theoretical publications.

Free-standing nanomechanical and nanophotonic structures in single-crystal diamond

NASA Astrophysics Data System (ADS)

Burek, Michael John

inventory of luminescent defect centers (many with direct optical access to highly coherent electron and nuclear spins). Diamond has many potential applications ranging from radio frequency nanoelectromechanical systems (RF-NEMS), to all-optical signal processing and quantum optics. Despite the commercial availability of wafer-scale nanocrystalline diamond thin films on foreign substrates (namely SiO2), this diamond-on-insulator (DOI) platform typically exhibits inferior material properties due to friction, scattering, and absorption losses at grain boundaries, significant surface roughness, and large interfacial stresses. In the absence of suitable heteroepitaxial diamond growth, substantial research and development efforts have focused on novel processing techniques to yield nanoscale single-crystal diamond mechanical and optical elements. In this thesis, we demonstrate a scalable 'angled-etching' nanofabrication method for realizing nanomechanical systems and nanophotonic networks starting from bulk single-crystal diamond substrates. Angled-etching employs anisotropic oxygen-based plasma etching at an oblique angle to the substrate surface, resulting in suspended optical structures with triangular cross-sections. Using this approach, we first realize single-crystal diamond nanomechanical resonant structures. These nanoscale diamond resonators exhibit high mechanical quality-factors (approaching Q ~ 105) with mechanical resonances up to 10 MHz. Next, we demonstrate engineered nanophotonic structures, specifically racetrack resonators and photonic crystal cavities, in bulk single-crystal diamond. Our devices feature large optical Q-factors, in excess of 10 5, and operate over a wide wavelength range, spanning visible and telecom. These newly developed high-Q diamond optical nanocavities open the door for a wealth of applications, ranging from nonlinear optics and chemical sensing, to quantum information processing and cavity optomechanics. Beyond isolated nanophotonic

Spin–cavity interactions between a quantum dot molecule and a photonic crystal cavity

PubMed Central

Vora, Patrick M.; Bracker, Allan S.; Carter, Samuel G.; Sweeney, Timothy M.; Kim, Mijin; Kim, Chul Soo; Yang, Lily; Brereton, Peter G.; Economou, Sophia E.; Gammon, Daniel

2015-01-01

The integration of InAs/GaAs quantum dots into nanophotonic cavities has led to impressive demonstrations of cavity quantum electrodynamics. However, these demonstrations are primarily based on two-level excitonic systems. Efforts to couple long-lived quantum dot electron spin states with a cavity are only now succeeding. Here we report a two-spin–cavity system, achieved by embedding an InAs quantum dot molecule within a photonic crystal cavity. With this system we obtain a spin singlet–triplet Λ-system where the ground-state spin splitting exceeds the cavity linewidth by an order of magnitude. This allows us to observe cavity-stimulated Raman emission that is highly spin-selective. Moreover, we demonstrate the first cases of cavity-enhanced optical nonlinearities in a solid-state Λ-system. This provides an all-optical, local method to control the spin exchange splitting. Incorporation of a highly engineerable quantum dot molecule into the photonic crystal architecture advances prospects for a quantum network. PMID:26184654

A superhigh-frequency optoelectromechanical system based on a slotted photonic crystal cavity

NASA Astrophysics Data System (ADS)

Sun, Xiankai; Zhang, Xufeng; Poot, Menno; Xiong, Chi; Tang, Hong X.

2012-11-01

We develop an all-integrated optoelectromechanical system that operates in the superhigh frequency band. This system is based on an ultrahigh-Q slotted photonic crystal (PhC) nanocavity formed by two PhC membranes, one of which is patterned with electrode and capacitively driven. The strong simultaneous electromechanical and optomechanical interactions yield efficient electrical excitation and sensitive optical transduction of the bulk acoustic modes of the PhC membrane. These modes are identified up to a frequency of 4.20 GHz, with their mechanical Q factors ranging from 240 to 1730. Directly linking signals in microwave and optical domains, such optoelectromechanical systems will find applications in microwave photonics in addition to those that utilize the electromechanical and optomechanical interactions separately.

Strain coupling between nitrogen vacancy centers and the mechanical motion of a diamond optomechanical crystal resonator

NASA Astrophysics Data System (ADS)

Cady, J. V.; Lee, K. W.; Ovartchaiyapong, P.; Bleszynski Jayich, A. C.

Several experiments have recently demonstrated coupling between nitrogen vacancy (NV) centers in diamond and mechanical resonators via crystal strain. In the strong coupling regime, such devices could realize applications critical to emerging quantum technologies, including phonon-mediated spin-spin interactions and mechanical cooling with the NV center1. An outstanding challenge for these devices is generating higher strain coupling in high frequency devices while maintaining the excellent coherence properties of the NV center and high mechanical quality factors. As a step toward these objectives, we demonstrate single-crystal diamond optomechanical crystal resonators with embedded NV centers. These devices host highly-confined GHz-scale mechanical modes that are isolated from mechanical clamping losses and generate strain profiles that allow for large strain coupling to NV centers far from noise-inducing surfaces.

Optomechanical coupling in phoxonic–plasmonic slab cavities with periodic metal strips

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Tzy-Rong; Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 20224, Taiwan; Huang, Yin-Chen

2015-05-07

We theoretically investigate the optomechanical (OM) coupling of submicron cavities formed in one-dimensional phoxonic–plasmonic slabs. The phoxonic–plasmonic slabs are structured by depositing periodic Ag strips onto the top surfaces of dielectric GaAs slabs to produce dual band gaps for both electromagnetic and acoustic waves, thereby inducing the coupling of surface plasmons with photons for tailoring the OM coupling. We quantify the OM coupling by calculating the temporal modulation of the optical resonance wavelength with the acoustic phonon-induced photoelastic (PE) and moving-boundary (MB) effects. We also consider the appearance of a uniform Ag layer on the bottom surface of the slabsmore » to modulate the photonic–plasmonic coupling. The results show that the PE and MB effects can be constructive or destructive in the overall OM coupling, and their magnitudes depend not only on the quality factors of the resonant modes but also on the mode area, mode overlap, and individual symmetries of the photonic–phononic mode pairs. Lowering the mode area could be effective for enhancing the OM coupling of subwavelength photons and phonons. This study introduces possible engineering applications to achieve enhanced interaction between photons and phonons in nanoscale OM devices.« less

Diabolical points in multi-scatterer optomechanical systems

PubMed Central

Chesi, Stefano; Wang, Ying-Dan; Twamley, Jason

2015-01-01

Diabolical points, which originate from parameter-dependent accidental degeneracies of a system's energy levels, have played a fundamental role in the discovery of the Berry phase as well as in photonics (conical refraction), in chemical dynamics, and more recently in novel materials such as graphene, whose electronic band structure possess Dirac points. Here we discuss diabolical points in an optomechanical system formed by multiple scatterers in an optical cavity with periodic boundary conditions. Such configuration is close to experimental setups using micro-toroidal rings with indentations or near-field scatterers. We find that the optomechanical coupling is no longer an analytic function near the diabolical point and demonstrate the topological phase arising through the mechanical motion. Similar to a Fabry-Perot resonator, the optomechanical coupling can grow with the number of scatterers. We also introduce a minimal quantum model of a diabolical point, which establishes a connection to the motion of an arbitrary-spin particle in a 2D parabolic quantum dot with spin-orbit coupling. PMID:25588627

Cavity cooling a single charged levitated nanosphere.

PubMed

Millen, J; Fonseca, P Z G; Mavrogordatos, T; Monteiro, T S; Barker, P F

2015-03-27

Optomechanical cavity cooling of levitated objects offers the possibility for laboratory investigation of the macroscopic quantum behavior of systems that are largely decoupled from their environment. However, experimental progress has been hindered by particle loss mechanisms, which have prevented levitation and cavity cooling in a vacuum. We overcome this problem with a new type of hybrid electro-optical trap formed from a Paul trap within a single-mode optical cavity. We demonstrate a factor of 100 cavity cooling of 400 nm diameter silica spheres trapped in vacuum. This paves the way for ground-state cooling in a smaller, higher finesse cavity, as we show that a novel feature of the hybrid trap is that the optomechanical cooling becomes actively driven by the Paul trap, even for singly charged nanospheres.

Cavity Cooling a Single Charged Levitated Nanosphere

NASA Astrophysics Data System (ADS)

Millen, J.; Fonseca, P. Z. G.; Mavrogordatos, T.; Monteiro, T. S.; Barker, P. F.

2015-03-01

Optomechanical cavity cooling of levitated objects offers the possibility for laboratory investigation of the macroscopic quantum behavior of systems that are largely decoupled from their environment. However, experimental progress has been hindered by particle loss mechanisms, which have prevented levitation and cavity cooling in a vacuum. We overcome this problem with a new type of hybrid electro-optical trap formed from a Paul trap within a single-mode optical cavity. We demonstrate a factor of 100 cavity cooling of 400 nm diameter silica spheres trapped in vacuum. This paves the way for ground-state cooling in a smaller, higher finesse cavity, as we show that a novel feature of the hybrid trap is that the optomechanical cooling becomes actively driven by the Paul trap, even for singly charged nanospheres.

A theoretical multi-reflection method for analysis of optomechanical behavior of the Fabry-Perot cavity with moving boundary condition

NASA Astrophysics Data System (ADS)

Bahrampour, A. R.; Vahedi, M.; Abdi, M.; Ghobadi, R.; Golshani, M.; Tofighi, S.; Parvin, B.

2011-09-01

The opto-mechanical coupling and the generation of Stokes and anti-Stokes frequencies in the in-band and intra-band regimes of operation of the Fabry-Perot cavity with a moving mirror on the basis of multi-reflection method (MRM) are described by a unique theory. The frequency characteristic function of the Fabry-Perot filter is modified. By increasing the amplitude of mirror oscillation the Fabry-Perot bandwidth increases and normal mode splitting occurred. The conversion efficiencies of the Stokes and anti-Stokes frequencies versus the mechanical amplitude of oscillation have an optimum value. Also, the delay function corresponding to the radiation pressure is obtained.

The crystal cavities of the New Jersey zeolite region

USGS Publications Warehouse

Schaller, Waldemar Theodore

1932-01-01

The crystal cavities present in the mineral complex of the New Jersey traprock region have long excited the interest of mineralogists. In 1914 Fenner made the first detailed and comprehensive study of these cavities and suggested that babingtonite was the original mineral. Soon after this anhydrite was found occupying parts of some of the cavities at one of the quarries. At this time, too, Wherry concluded that glauberite was the original mineral of some of the cavities because of his studies of similar crystal cavities in Triassic shale at different places.

Mode competition and hopping in optomechanical nano-oscillators

NASA Astrophysics Data System (ADS)

Zhang, Xingwang; Lin, Tong; Tian, Feng; Du, Han; Zou, Yongchao; Chau, Fook Siong; Zhou, Guangya

2018-04-01

We investigate the inter-mode nonlinear interaction in the multi-mode optomechanical nano-oscillator which consists of coupled silicon nanocantilevers, where the integrated photonic crystal nanocavities provide the coupling between the optical and mechanical modes. Due to the self-saturation and cross-saturation of the mechanical gain, the inter-mode competition is observed, which leads to the bistable operation of the optomechanical nano-oscillator: only one of the mechanical modes can oscillate at any one time, and the oscillation of one mode extremely suppresses that of the other with a side mode suppression ratio (SMSR) up to 40 dB. In the meantime, mode hopping, i.e., the optomechanical oscillation switches from one mode to the other, is also observed and found to be able to be provoked by excitation laser fluctuations.

Reflectivity and transmissivity of a cavity coupled to a nanoparticle

NASA Astrophysics Data System (ADS)

Khan, M. A.; Farooq, K.; Hou, S. C.; Niaz, Shanawer; Yi, X. X.

2014-07-01

Any dielectric nanoparticle moving inside an optical cavity generates an optomechanical interaction. In this paper, we theoretically analyze the light scattering of an optomechanical cavity which strongly interacts with a dielectric nanoparticle. The cavity is driven by an external laser field. This interaction gives rise to different dynamics that can be used to cool, trap and levitate nanoparticle. We analytically calculate reflection and transmission rate of the cavity field, and study the time evolution of the intracavity field, momentum and position of the nanoparticle. We find the nanoparticle occupies a discrete position inside the cavity. This effect can be exploited to separate nanoparticle and couplings between classical particles and quantized fields.

Ultrafast optomechanical pulse picking

NASA Astrophysics Data System (ADS)

Lilienfein, Nikolai; Holzberger, Simon; Pupeza, Ioachim

2017-01-01

State-of-the-art optical switches for coupling pulses into and/or out of resonators are based on either the electro-optic or the acousto-optic effect in transmissive elements. In high-power applications, the damage threshold and other nonlinear and thermal effects in these elements impede further improvements in pulse energy, duration, and average power. We propose a new optomechanical switching concept which is based solely on reflective elements and is suitable for switching times down to the ten-nanosecond range. To this end, an isolated section of a beam path is moved in a system comprising mirrors rotating at a high angular velocity and stationary imaging mirrors, without affecting the propagation of the beam thereafter. We discuss three variants of the concept and exemplify practical parameters for its application in regenerative amplifiers and stack-and-dump enhancement cavities. We find that optomechanical pulse picking has the potential to achieve switching rates of up to a few tens of kilohertz while supporting pulse energies of up to several joules.

Lasing from active optomechanical resonators

PubMed Central

Czerniuk, T.; Brüggemann, C.; Tepper, J.; Brodbeck, S.; Schneider, C.; Kamp, M.; Höfling, S.; Glavin, B. A.; Yakovlev, D. R.; Akimov, A. V.; Bayer, M.

2014-01-01

Planar microcavities with distributed Bragg reflectors (DBRs) host, besides confined optical modes, also mechanical resonances due to stop bands in the phonon dispersion relation of the DBRs. These resonances have frequencies in the 10- to 100-GHz range, depending on the resonator’s optical wavelength, with quality factors exceeding 1,000. The interaction of photons and phonons in such optomechanical systems can be drastically enhanced, opening a new route towards the manipulation of light. Here we implemented active semiconducting layers into the microcavity to obtain a vertical-cavity surface-emitting laser (VCSEL). Thereby, three resonant excitations—photons, phonons and electrons—can interact strongly with each other providing modulation of the VCSEL laser emission: a picosecond strain pulse injected into the VCSEL excites long-living mechanical resonances therein. As a result, modulation of the lasing intensity at frequencies up to 40 GHz is observed. From these findings, prospective applications of active optomechanical resonators integrated into nanophotonic circuits may emerge. PMID:25008784

Optical microfiber-based photonic crystal cavity

NASA Astrophysics Data System (ADS)

Yu, Yang; Sun, Yi-zhi; Andrews, Steve; Li, Zhi-yuan; Ding, Wei

2016-01-01

Using a focused ion beam milling technique, we fabricate broad stop band (∼10% wide) photonic crystal (PhC) cavities in adiabatically-tapered silica fibers. Abrupt structural design of PhC mirrors efficiently reduces radiation loss, increasing the cavity finesse to ∼7.5. Further experiments and simulations verify that the remaining loss is mainly due to Ga ion implantation. Such a microfiber PhC cavity probably has potentials in many light-matter interaction applications.

Tunable optical nonreciprocity and a phonon-photon router in an optomechanical system with coupled mechanical and optical modes

NASA Astrophysics Data System (ADS)

Li, Guolong; Xiao, Xiao; Li, Yong; Wang, Xiaoguang

2018-02-01

We propose a multimode optomechanical system to realize tunable optical nonreciprocity that has the prospect of making an optical diode for information technology. The proposed model consists of two subsystems, each of which contains two optical cavities, injected with a classical field and a quantum signal via a 50:50 beam splitter, and a mechanical oscillator, coupled to both cavities via optomechanical coupling. Meanwhile two cavities and an oscillator in a subsystem are respectively coupled to their corresponding cavities and an oscillator in the other subsystem. Our scheme yields nonreciprocal effects at different frequencies with opposite directions, but each effective linear optomechanical coupling can be controlled by an independent classical one-frequency pump. With this setup one is able to apply quantum states with large fluctuations, which extends the scope of applicable quantum states, and exploit the independence of paths. Moreover, the optimal frequencies for nonreciprocal effects can be controlled by adjusting the relevant parameters. We also exhibit the path switching of two directions, from a mechanical input to two optical output channels, via tuning the signal frequency. In experiment, the considered scheme can be tuned to reach small damping rates of the oscillators relative to those of the cavities, which is more practical and requires less power than in previous schemes.

Single-photon transport through a waveguide coupling to a quadratic optomechanical system

NASA Astrophysics Data System (ADS)

Qiao, Lei

2017-07-01

We study the coherent transport of a single photon, which propagates in a one-dimensional waveguide and is scattered by a quadratic optomechanical system. Our approach, which is based on the Lippmann-Schwinger equation, gives an analytical solution to describe the single-photon transmission and reflection properties. We analyze the transport spectra and find they are not only related to the optomechanical system's energy-level structure, but also dependent on the optomechanical system's inherent parameters. For the existence of atomic degrees of freedom, we get a Rabi-splitting-like or an electromagnetically induced transparency (EIT)-like spectrum, depending on the atom-cavity coupling strength. Here, we focus on the single-photon strong-coupling regime so that single-quantum effects could be seen.

Self-cavity lasing in optically pumped single crystals of p-sexiphenyl

NASA Astrophysics Data System (ADS)

Yanagi, Hisao; Tamura, Kenji; Sasaki, Fumio

2016-08-01

Organic single-crystal self-cavities are prepared by solution growth of p-sexiphenyl (p-6P). Based on Fabry-Pérot feedback inside a quasi-lozenge-shaped platelet crystal, edge-emitting laser is obtained under optical pumping. The multimode lasing band appears at the 0-1 or 0-2 vibronic progressions depending on the excitation conditions which affect the self-absorption effect. Cavity-size dependence of amplified spontaneous emission (ASE) is investigated with laser-etched single crystals of p-6P. As the cavity length of square-shaped crystal is reduced from 100 to 10 μm, ASE threshold fluence is decreased probably due to size-dependent light confinement in the crystal cavity.

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. Copyright © 2016 Elsevier B.V. All rights reserved.

Nano-optomechanical transducer

DOEpatents

Rakich, Peter T; El-Kady, Ihab F; Olsson, Roy H; Su, Mehmet Fatih; Reinke, Charles; Camacho, Ryan; Wang, Zheng; Davids, Paul

2013-12-03

A nano-optomechanical transducer provides ultrabroadband coherent optomechanical transduction based on Mach-wave emission that uses enhanced photon-phonon coupling efficiencies by low impedance effective phononic medium, both electrostriction and radiation pressure to boost and tailor optomechanical forces, and highly dispersive electromagnetic modes that amplify both electrostriction and radiation pressure. The optomechanical transducer provides a large operating bandwidth and high efficiency while simultaneously having a small size and minimal power consumption, enabling a host of transformative phonon and signal processing capabilities. These capabilities include optomechanical transduction via pulsed phonon emission and up-conversion, broadband stimulated phonon emission and amplification, picosecond pulsed phonon lasers, broadband phononic modulators, and ultrahigh bandwidth true time delay and signal processing technologies.

Symmetry-breaking oscillations in membrane optomechanics

NASA Astrophysics Data System (ADS)

Wurl, C.; Alvermann, A.; Fehske, H.

2016-12-01

We study the classical dynamics of a membrane inside a cavity in the situation where this optomechanical system possesses a reflection symmetry. Symmetry breaking occurs through supercritical and subcritical pitchfork bifurcations of the static fixed-point solutions. Both bifurcations can be observed through variation of the laser-cavity detuning, which gives rise to a boomerang-like fixed-point pattern with hysteresis. The symmetry-breaking fixed points evolve into self-sustained oscillations when the laser intensity is increased. In addition to the analysis of the accompanying Hopf bifurcations we describe these oscillations at finite amplitudes with an ansatz that fully accounts for the frequency shift relative to the natural membrane frequency. We complete our study by following the route to chaos for the membrane dynamics.

Optomechanical measurement of photon spin angular momentum and optical torque in integrated photonic devices.

PubMed

He, Li; Li, Huan; Li, Mo

2016-09-01

Photons carry linear momentum and spin angular momentum when circularly or elliptically polarized. During light-matter interaction, transfer of linear momentum leads to optical forces, whereas transfer of angular momentum induces optical torque. Optical forces including radiation pressure and gradient forces have long been used in optical tweezers and laser cooling. In nanophotonic devices, optical forces can be significantly enhanced, leading to unprecedented optomechanical effects in both classical and quantum regimes. In contrast, to date, the angular momentum of light and the optical torque effect have only been used in optical tweezers but remain unexplored in integrated photonics. We demonstrate the measurement of the spin angular momentum of photons propagating in a birefringent waveguide and the use of optical torque to actuate rotational motion of an optomechanical device. We show that the sign and magnitude of the optical torque are determined by the photon polarization states that are synthesized on the chip. Our study reveals the mechanical effect of photon's polarization degree of freedom and demonstrates its control in integrated photonic devices. Exploiting optical torque and optomechanical interaction with photon angular momentum can lead to torsional cavity optomechanics and optomechanical photon spin-orbit coupling, as well as applications such as optomechanical gyroscopes and torsional magnetometry.

Optomechanical measurement of photon spin angular momentum and optical torque in integrated photonic devices

PubMed Central

He, Li; Li, Huan; Li, Mo

2016-01-01

Photons carry linear momentum and spin angular momentum when circularly or elliptically polarized. During light-matter interaction, transfer of linear momentum leads to optical forces, whereas transfer of angular momentum induces optical torque. Optical forces including radiation pressure and gradient forces have long been used in optical tweezers and laser cooling. In nanophotonic devices, optical forces can be significantly enhanced, leading to unprecedented optomechanical effects in both classical and quantum regimes. In contrast, to date, the angular momentum of light and the optical torque effect have only been used in optical tweezers but remain unexplored in integrated photonics. We demonstrate the measurement of the spin angular momentum of photons propagating in a birefringent waveguide and the use of optical torque to actuate rotational motion of an optomechanical device. We show that the sign and magnitude of the optical torque are determined by the photon polarization states that are synthesized on the chip. Our study reveals the mechanical effect of photon’s polarization degree of freedom and demonstrates its control in integrated photonic devices. Exploiting optical torque and optomechanical interaction with photon angular momentum can lead to torsional cavity optomechanics and optomechanical photon spin-orbit coupling, as well as applications such as optomechanical gyroscopes and torsional magnetometry. PMID:27626072

Numerical demonstration of neuromorphic computing with photonic crystal cavities.

PubMed

Laporte, Floris; Katumba, Andrew; Dambre, Joni; Bienstman, Peter

2018-04-02

We propose a new design for a passive photonic reservoir computer on a silicon photonics chip which can be used in the context of optical communication applications, and study it through detailed numerical simulations. The design consists of a photonic crystal cavity with a quarter-stadium shape, which is known to foster interesting mixing dynamics. These mixing properties turn out to be very useful for memory-dependent optical signal processing tasks, such as header recognition. The proposed, ultra-compact photonic crystal cavity exhibits a memory of up to 6 bits, while simultaneously accepting bitrates in a wide region of operation. Moreover, because of the inherent low losses in a high-Q photonic crystal cavity, the proposed design is very power efficient.

Quantum limits to gravity estimation with optomechanics

NASA Astrophysics Data System (ADS)

Armata, F.; Latmiral, L.; Plato, A. D. K.; Kim, M. S.

2017-10-01

We present a table-top quantum estimation protocol to measure the gravitational acceleration g by using an optomechanical cavity. In particular, we exploit the nonlinear quantum light-matter interaction between an optical field and a massive mirror acting as mechanical oscillator. The gravitational field influences the system dynamics affecting the phase of the cavity field during the interaction. Reading out such a phase carried by the radiation leaking from the cavity, we provide an estimate of the gravitational acceleration through interference measurements. Contrary to previous studies, having adopted a fully quantum description, we are able to propose a quantum analysis proving the ultimate bound to the estimability of the gravitational acceleration and verifying optimality of homodyne detection. Noticeably, thanks to the light-matter decoupling at the measurement time, no initial cooling of the mechanical oscillator is demanded in principle.

An integrated low phase noise radiation-pressure-driven optomechanical oscillator chipset

PubMed Central

Luan, Xingsheng; Huang, Yongjun; Li, Ying; McMillan, James F.; Zheng, Jiangjun; Huang, Shu-Wei; Hsieh, Pin-Chun; Gu, Tingyi; Wang, Di; Hati, Archita; Howe, David A.; Wen, Guangjun; Yu, Mingbin; Lo, Guoqiang; Kwong, Dim-Lee; Wong, Chee Wei

2014-01-01

High-quality frequency references are the cornerstones in position, navigation and timing applications of both scientific and commercial domains. Optomechanical oscillators, with direct coupling to continuous-wave light and non-material-limited f × Q product, are long regarded as a potential platform for frequency reference in radio-frequency-photonic architectures. However, one major challenge is the compatibility with standard CMOS fabrication processes while maintaining optomechanical high quality performance. Here we demonstrate the monolithic integration of photonic crystal optomechanical oscillators and on-chip high speed Ge detectors based on the silicon CMOS platform. With the generation of both high harmonics (up to 59th order) and subharmonics (down to 1/4), our chipset provides multiple frequency tones for applications in both frequency multipliers and dividers. The phase noise is measured down to −125 dBc/Hz at 10 kHz offset at ~400 μW dropped-in powers, one of the lowest noise optomechanical oscillators to date and in room-temperature and atmospheric non-vacuum operating conditions. These characteristics enable optomechanical oscillators as a frequency reference platform for radio-frequency-photonic information processing. PMID:25354711

Synchronization of an optomechanical system to an external drive

NASA Astrophysics Data System (ADS)

Amitai, Ehud; Lörch, Niels; Nunnenkamp, Andreas; Walter, Stefan; Bruder, Christoph

2017-05-01

Optomechanical systems driven by an effective blue-detuned laser can exhibit self-sustained oscillations of the mechanical oscillator. These self-oscillations are a prerequisite for the observation of synchronization. Here, we study the synchronization of the mechanical oscillations to an external reference drive. We study two cases of reference drives: (1) an additional laser applied to the optical cavity; (2) a mechanical drive applied directly to the mechanical oscillator. Starting from a master equation description, we derive a microscopic Adler equation for both cases, valid in the classical regime in which the quantum shot noise of the mechanical self-oscillator does not play a role. Furthermore, we numerically show that, in both cases, synchronization arises also in the quantum regime. The optomechanical system is therefore a good candidate for the study of quantum synchronization.

Qubit assisted enhancement of quantum correlations in an optomechanical system

NASA Astrophysics Data System (ADS)

Chakraborty, Subhadeep; Sarma, Amarendra K.

2018-05-01

We perform a theoretical study on quantum correlations in an optomechanical system where the mechanical mirror is perturbatively coupled to an auxiliary qubit. In our study, we consider logarithmic negativity to quantify the degree of stationary entanglement between the cavity field and mechanical mirror, and, Gaussian quantum discord as a witness of the quantumness of the correlation beyond entanglement. Utilizing experimentally feasible parameters, we show that both entanglement and quantum discord enhance significantly with increase in mirror-qubit coupling. Moreover, we find that in presence of the mirror-qubit coupling entanglement could be generated at a considerably lower optomechanical coupling strength, which is also extremely robust against the environmental temperature. Overall, our proposed scheme offers some considerable advantages for realizing the continuous-variable quantum information and communication.

Novel approaches to optomechanical transduction

NASA Astrophysics Data System (ADS)

Cernotik, Ondrej; Hammerer, Klemens

In recent years, mechanical oscillators received attention as a promising tool for frequency conversion between microwaves and light. A general, bi-directional transducer with high efficiency is still far from reach of current technology; finding new strategies for optomechanical transduction allows us to relax the requirements and bring these systems closer to an experimental realization. An interesting example is generation of entanglement between two superconducting qubits using measurement and postselection. Here, the mechanical oscillators interacts directly with the superconducting transmon qubit in such a way that it feels a qubit-state dependent force. This force can then be read out using a cavity field; reading out two such systems sequentially realizes an effective total spin measurement. Starting from a suitable initial state and employing postselection, entanglement can be generated. Another interesting approach is to use an array of optomechanical transducers in which the output fields of one transducer are fed into the input of the next. The periodicity of the array results in a joint dispersion relation for the propagating microwave and optical fields. The resulting structure can be used to control the conversion bandwidth and forward and backward scattering.

Near-field levitated quantum optomechanics with nanodiamonds

NASA Astrophysics Data System (ADS)

Juan, M. L.; Molina-Terriza, G.; Volz, T.; Romero-Isart, O.

2016-08-01

We theoretically show that the dipole force of an ensemble of quantum emitters embedded in a dielectric nanosphere can be exploited to achieve near-field optical levitation. The key ingredient is that the polarizability from the ensemble of embedded quantum emitters can be larger than the bulk polarizability of the sphere, thereby enabling the use of repulsive optical potentials and consequently the levitation using optical near fields. In levitated cavity quantum optomechanics, this could be used to boost the single-photon coupling by combining larger polarizability to mass ratio, larger field gradients, and smaller cavity volumes while remaining in the resolved sideband regime and at room temperature. A case study is done with a nanodiamond containing a high density of silicon-vacancy color centers that is optically levitated in the evanescent field of a tapered nanofiber and coupled to a high-finesse microsphere cavity.

Graphene as a Platform for Hybrid Optomechanical Devices

NASA Astrophysics Data System (ADS)

Bouchiat, Vincent; Reserbat-Plantey, Antoine; Kalita, Dipankar; Marty, Laetitia; Arcizet, Olivier; Bendiab, Nedjma

2013-03-01

Graphene is known for providing a flat 2D material with outstanding optical, electrical and mechanical properties. We propose to take advantage of all three features by developing an optomechanical platform based on cantilevers made of freestanding multilayer graphene connected to an electrode. In this talk I will present several examples of a simple optomechanical systems involving a multilayer graphene suspended cantilevers that can act as a mirror closing an optical cavity. By varying the gate voltage applied on the mirror, its angle can be adjusted on a wide range (exceeding the wavelength of the incoming light) and its motion can be actuated and followed in real time from DC up to the tens of MHz range. Detection of elastic and inelastic scattered light can be performed. It allows simultaneous detection of motion, local stress and temperature of the membrane. A fully spectral detection of NEMS resonance is presented (1) and allows a novel optomechanical scheme based on coupling between motion and light through the dynamic mechanical stress. Further applications are presented as well such as a gate tunable enhancement of the Raman signal of molecular species adsorbed on the graphene platform. (1) Reserbat-Plantey, A., et al, Nature Nanotechnology, vol. 7, 151-155. (2012).

Mesoscopic chaos mediated by Drude electron-hole plasma in silicon optomechanical oscillators

PubMed Central

Wu, Jiagui; Huang, Shu-Wei; Huang, Yongjun; Zhou, Hao; Yang, Jinghui; Liu, Jia-Ming; Yu, Mingbin; Lo, Guoqiang; Kwong, Dim-Lee; Duan, Shukai; Wei Wong, Chee

2017-01-01

Chaos has revolutionized the field of nonlinear science and stimulated foundational studies from neural networks, extreme event statistics, to physics of electron transport. Recent studies in cavity optomechanics provide a new platform to uncover quintessential architectures of chaos generation and the underlying physics. Here, we report the generation of dynamical chaos in silicon-based monolithic optomechanical oscillators, enabled by the strong and coupled nonlinearities of two-photon absorption induced Drude electron–hole plasma. Deterministic chaotic oscillation is achieved, and statistical and entropic characterization quantifies the chaos complexity at 60 fJ intracavity energies. The correlation dimension D2 is determined at 1.67 for the chaotic attractor, along with a maximal Lyapunov exponent rate of about 2.94 times the fundamental optomechanical oscillation for fast adjacent trajectory divergence. Nonlinear dynamical maps demonstrate the subharmonics, bifurcations and stable regimes, along with distinct transitional routes into chaos. This provides a CMOS-compatible and scalable architecture for understanding complex dynamics on the mesoscopic scale. PMID:28598426

Demonstration of nonreciprocity in a microwave cavity optomechanical circuit

NASA Astrophysics Data System (ADS)

Peterson, Gabriel; Lecocq, Florent; Kotler, Shlomi; Cicak, Katarina; Simmonds, Raymond; Aumentado, Jose; Teufel, John

The ability to engineer nonreciprocal interactions is essential for many applications including quantum signal processing and quantum transduction. While attributes such as high efficiency and low added noise are always beneficial, for quantum applications these metrics are crucial. Here we present recent experimental results on a parametric, nonreciprocal microwave circuit based on the optomechanical interaction between a superconducting microwave resonator and a mechanically compliant vacuum gap capacitor. Unlike standard Faraday-based circulators, this parametric interaction does not require magnetic fields, and the direction of circulation can be controlled dynamically in situ. Looking forward, such devices could enable programmable, high-efficiency connections between disparate nodes of a quantum network.

Storage and retrieval of quantum information with a hybrid optomechanics-spin system

NASA Astrophysics Data System (ADS)

Feng, Zhi-Bo; Zhang, Jian-Qi; Yang, Wan-Li; Feng, Mang

2016-08-01

We explore an efficient scheme for transferring the quantum state between an optomechanical cavity and an electron spin of diamond nitrogen-vacancy center. Assisted by a mechanical resonator, quantum information can be controllably stored (retrieved) into (from) the electron spin by adjusting the external field-induced detuning or coupling. Our scheme connects effectively the cavity photon and the electron spin and transfers quantum states between two regimes with large frequency difference. The experimental feasibility of our protocol is justified with accessible laboratory parameters.

Refractive index dependence of L3 photonic crystal nano-cavities.

PubMed

Adawi, A M; Chalcraft, A R; Whittaker, D M; Lidzey, D G

2007-10-29

We model the optical properties of L3 photonic crystal nano-cavities as a function of the photonic crystal membrane refractive index n using a guided mode expansion method. Band structure calculations revealed that a TE-like full band-gap exists for materials of refractive index as low as 1.6. The Q-factor of such cavities showed a super-linear increase with refractive index. By adjusting the relative position of the cavity side holes, the Q-factor was optimised as a function of the photonic crystal membrane refractive index n over the range 1.6 to 3.4. Q-factors in the range 3000-8000 were predicted from absorption free materials in the visible range with refractive index between 2.45 and 2.8.

Exploring corrections to the Optomechanical Hamiltonian.

PubMed

Sala, Kamila; Tufarelli, Tommaso

2018-06-14

We compare two approaches for deriving corrections to the "linear model" of cavity optomechanics, in order to describe effects that are beyond first order in the radiation pressure coupling. In the regime where the mechanical frequency is much lower than the cavity one, we compare: (I) a widely used phenomenological Hamiltonian conserving the photon number; (II) a two-mode truncation of C. K. Law's microscopic model, which we take as the "true" system Hamiltonian. While these approaches agree at first order, the latter model does not conserve the photon number, resulting in challenging computations. We find that approach (I) allows for several analytical predictions, and significantly outperforms the linear model in our numerical examples. Yet, we also find that the phenomenological Hamiltonian cannot fully capture all high-order corrections arising from the C. K. Law model.

Cavity Pull Rod: Device to Promote Single Crystal Growth from the Melt

NASA Technical Reports Server (NTRS)

Goldsby, Jon (Inventor)

2017-01-01

A pull rod for use in producing a single crystal from a molten alloy is provided that includes an elongated rod having a first end and a second end, a first cavity defined at the first end and a second cavity defined at the first end and in communication with the first cavity. The first cavity receives the molten alloy and the second cavity vents a gas from the molten alloy to thereby template a single crystal when the pull rod is dipped into and extracted from the molten alloy.

Experimental opto-mechanics with levitated nanoparticles: towards quantum control and thermodynamic cycles (Presentation Recording)

NASA Astrophysics Data System (ADS)

Kiesel, Nikolai; Blaser, Florian; Delic, Uros; Grass, David; Dechant, Andreas; Lutz, Eric; Bathaee, Marzieh; Aspelmeyer, Markus

2015-08-01

Combining optical levitation and cavity optomechanics constitutes a promising approach to prepare and control the motional quantum state of massive objects (>10^9 amu). This, in turn, would represent a completely new type of light-matter interface and has, for example, been predicted to enable experimental tests of macrorealistic models or of non-Newtonian gravity at small length scales. Such ideas have triggered significant experimental efforts to realizing such novel systems. To this end, we have recently successfully demonstrated cavity-cooling of a levitated sub-micron silica particle in a classical regime at a pressure of approximately 1mbar. Access to higher vacuum of approx. 10^-6 mbar has been demonstrated using 3D-feedback cooling in optical tweezers without cavity-coupling. Here we will illustrate our strategy towards trapping, 3D-cooling and quantum control of nanoparticles in ultra-high vacuum using cavity-based feedback cooling methods and clean particle loading with hollow-core photonic crystal fibers. We will also discuss the current experimental progress both in 3D-cavity cooling and HCPCF-based transport of nanoparticles. As yet another application of cavity-controlled levitated nanoparticles we will show how to implement a thermodynamic Sterling cycle operating in the underdamped regime. We present optimized protocols with respect to efficiency at maximum power in this little explored regime. We also show that the excellent level of control in our system will allow reproducing all relevant features of such optimized protocols. In a next step, this will enable studies of thermodynamics cycles in a regime where the quantization of the mechanical motion becomes relevant.

Cavity optomechanical coupling assisted by an atomic gas

NASA Astrophysics Data System (ADS)

Ian, H.; Gong, Z. R.; Liu, Yu-Xi; Sun, C. P.; Nori, Franco

2008-07-01

We theoretically study a cavity filled with atoms, which provides the optical-mechanical interaction between the modified cavity photonic field and a oscillating mirror at one end. We show that the cavity field “dresses” these atoms, producing two types of polaritons, effectively enhancing the radiation pressure of the cavity field upon the oscillating mirror, as well as establishing an additional squeezing mode of the oscillating mirror. This squeezing produces an adiabatic entanglement, which is absent in usual vacuum cavities, between the oscillating mirror and the rest of the system. We analyze the entanglement and quantify it using the Loschmidt echo and fidelity.

Nonperturbative Dynamical Casimir Effect in Optomechanical Systems: Vacuum Casimir-Rabi Splittings

NASA Astrophysics Data System (ADS)

Macrı, Vincenzo; Ridolfo, Alessandro; Di Stefano, Omar; Kockum, Anton Frisk; Nori, Franco; Savasta, Salvatore

2018-01-01

We study the dynamical Casimir effect using a fully quantum-mechanical description of both the cavity field and the oscillating mirror. We do not linearize the dynamics, nor do we adopt any parametric or perturbative approximation. By numerically diagonalizing the full optomechanical Hamiltonian, we show that the resonant generation of photons from the vacuum is determined by a ladder of mirror-field vacuum Rabi splittings. We find that vacuum emission can originate from the free evolution of an initial pure mechanical excited state, in analogy with the spontaneous emission from excited atoms. By considering a coherent drive of the mirror, using a master-equation approach to take losses into account, we are able to study the dynamical Casimir effect for optomechanical coupling strengths ranging from weak to ultrastrong. We find that a resonant production of photons out of the vacuum can be observed even for mechanical frequencies lower than the cavity-mode frequency. Since high mechanical frequencies, which are hard to achieve experimentally, were thought to be imperative for realizing the dynamical Casimir effect, this result removes one of the major obstacles for the observation of this long-sought effect. We also find that the dynamical Casimir effect can create entanglement between the oscillating mirror and the radiation produced by its motion in the vacuum field, and that vacuum Casimir-Rabi oscillations can occur. Finally, we also show that all these findings apply not only to optomechanical systems, but also to parametric amplifiers operating in the fully quantum regime.

High-Q silicon-on-insulator slot photonic crystal cavity infiltrated by a liquid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caër, Charles; Le Roux, Xavier; Cassan, Eric, E-mail: eric.cassan@u-psud.fr

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.

Bathed, Strained, Attenuated, Annihilated: Towards Quantum Optomechanics

NASA Astrophysics Data System (ADS)

Pepper, Brian Jeffrey

The field of optomechanics studies tiny devices that can be pushed mechanically by light. It is an extremely promising avenue towards tests of quantum mechanics on a macroscopic scale, by transferring quantum states of light to nano- or micromechanical objects. This dissertation concerns a long term research program to create quantum superpositions of a macroscopic mirror in an optomechanical cavity. This dissertation has two broad thrusts. The first focuses on microfabrication of a new type of device called optomechanical trampoline resonators, consisting of a small mirror on a cross-shaped tensed silicon nitride membrane. Devices have been fabricated with high mechanical and optical quality, including a 300 kHz device with quality factor 480,000, as well as a device of optical finesse 107,000. These devices are well into the sideband-resolved regime and suitable for optical cooling to the quantum ground state. One such device has been optically cooled to approximately 10 phonons. The second major thrust is theoretical. Creating a macroscopic superposition is a challenging problem, requiring optical cooling to the ground state, strong coupling, extremely high optical finesse and extremely low frequency. A realistic assessment of achievable parameters indicates that it is possible to achieve ground state cooling or strong coupling, but not both. This dissertation proposes a new technique using postselection to achieve macroscopic superpositions with only weak coupling. This relaxes some of the required parameters by orders of magnitude. Prospects for observing hypothetical novel decoherence mechanisms are also discussed.

Directional impulse response of a large cavity inside a sonic crystal.

PubMed

Spiousas, Ignacio; Eguia, Manuel C

2012-10-01

Both temporal and directional responses of a cavity inside a two-dimensional sonic crystal are investigated. The size of the cavity is large compared to the lattice parameter and the wavelength for the frequency range of interest. Hence, a hybrid method to compute the response is proposed, combining multiscattering theory for the calculation of the reflective properties of the sonic crystal with a modified ray-tracing algorithm for the sound propagation within the cavity. The response of this enclosure displays resonances for certain frequency bands that depend on the geometry of the lattice and the cavity. When a full band gap exists in the sonic crystal, rays cannot propagate through the medium and total reflection occurs for all incidence angles, leading to strong resonances with an isotropic intensity field inside the cavity. When only some propagation directions are forbidden, total reflection occurs for certain ranges of incidence angles, and resonances can also be elicited but with a highly anisotropic intensity field. The spectrum of resonances of the cavity is strongly affected by changes in the lattice geometry, suggesting that they can be tailored to some extent, a feature that can lead to potential applications in architectural acoustics.

Spin-orbit optomechanics of optically levitated chiral Bragg microspheres

NASA Astrophysics Data System (ADS)

Tkachenko, Georgiy; Rafayelyan, Mushegh; Brasselet, Etienne

2017-05-01

We explore the spin-orbit nature of the optical torque exerted on chiral liquid-crystal microspheres exhibiting circular Bragg reflection. Experimental investigation relies on the direct optomechanical observation of spinning liquid-crystal droplets immersed in water and held in a circularly polarized laser levitator. More generally, we anticipate that the total angular momentum transfer per photon may depart from the commonly assumed spin-only ±2 ℏ contribution, when the topological features of the illuminated microsphere are taken into account.

Enhanced photoelastic modulation in silica phononic crystal cavities

NASA Astrophysics Data System (ADS)

Kim, Ingi; Iwamoto, Satoshi; Arakawa, Yasuhiko

2018-04-01

The enhanced photoelastic modulation in quasi-one-dimensional (1D) phononic crystal (PnC) cavities made of fused silica is experimentally demonstrated. A confined acoustic wave in the cavity can induce a large birefringence through the photoelastic effect and enable larger optical modulation amplitude at the same acoustic power. We observe a phase retardation of ∼26 mrad of light passing through the cavity when the exciting acoustic frequency is tuned to the cavity mode resonance of ∼500 kHz at 2.5 V. In the present experiment, a 16-fold enhancement of retardation in the PnC cavity is demonstrated compared with that in a bar-shaped silica structure. Spatially resolved optical retardation measurement reveals that the large retardation is realized only around the cavity reflecting the localized nature of the acoustic cavity mode. The enhanced interactions between acoustic waves and light can be utilized to improve the performance of acousto-optic devices such as photoelastic modulators.

Reservoir-engineered entanglement in a hybrid modulated three-mode optomechanical system

NASA Astrophysics Data System (ADS)

Liao, Chang-Geng; Chen, Rong-Xin; Xie, Hong; Lin, Xiu-Min

2018-04-01

We propose an effective approach for generating highly pure and strong cavity-mechanical entanglement (or optical-microwave entanglement) in a hybrid modulated three-mode optomechanical system. By applying two-tone driving to the cavity and modulating the coupling strength between two mechanical oscillators (or between a mechanical oscillator and a transmission line resonator), we obtain an effective Hamiltonian where an intermediate mechanical mode acting as an engineered reservoir cools the Bogoliubov modes of two target system modes via beam-splitter-like interactions. In this way, the two target modes are driven to two-mode squeezed states in the stationary limit. In particular, we discuss the effects of cavity-driving detuning on the entanglement and the purity. It is found that the cavity-driving detuning plays a critical role in the goal of acquiring highly pure and strongly entangled steady states.

High-Q silica zipper cavity for optical radiation pressure driven MOMS switch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tetsumoto, Tomohiro; Tanabe, Takasumi, E-mail: takasumi@elec.keio.ac.jp

2014-07-15

We design a silica zipper cavity that has high optical and mechanical Q (quality factor) values and demonstrate numerically the feasibility of a radiation pressure driven micro opto-mechanical system (MOMS) directional switch. The silica zipper cavity has an optical Q of 4.0 × 10{sup 4} and an effective mode volume V{sub mode} of 0.67λ{sup 3} when the gap between two cavities is 34 nm. The mechanical Q (Q{sub m}) is determined by thermo-elastic damping and is 2.0 × 10{sup 6} in a vacuum at room temperature. The opto-mechanical coupling rate g{sub OM} is as high as 100 GHz/nm, which allowsmore » us to move the directional cavity-waveguide system and switch 1550-nm light with 770-nm light by controlling the radiation pressure.« less

Solid-state-based analog of optomechanics

DOE PAGES

Naumann, Nicolas L.; Droenner, Leon; Carmele, Alexander; ...

2016-09-01

In this study, we investigate a semiconductor quantum dot as a microscopic analog of a basic optomechanical setup. We show that optomechanical features can be reproduced by the solid-state platform, arising from parallels of the underlying interaction processes, which in the optomechanical case is the radiation pressure coupling and in the semiconductor case the electron–phonon coupling. We discuss bistabilities, lasing, and phonon damping, and recover the same qualitative behaviors for the semiconductor and the optomechanical cases expected for low driving strengths. However, in contrast to the optomechanical case, distinct signatures of higher order processes arise in the semiconductor model.

Flexible nanomembrane photonic-crystal cavities for tensilely strained-germanium light emission

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Jian; Wang, Xiaowei; Paiella, Roberto

2016-06-13

Flexible photonic-crystal cavities in the form of Si-column arrays embedded in polymeric films are developed on Ge nanomembranes using direct membrane assembly. The resulting devices can sustain large biaxial tensile strain under mechanical stress, as a way to enhance the Ge radiative efficiency. Pronounced emission peaks associated with photonic-crystal cavity resonances are observed in photoluminescence measurements. These results show that ultrathin nanomembrane active layers can be effectively coupled to an optical cavity, while still preserving their mechanical flexibility. Thus, they are promising for the development of strain-enabled Ge lasers, and more generally uniquely flexible optoelectronic devices.

Realizing a Circuit Analog of an Optomechanical System with Longitudinally Coupled Superconducting Resonators

NASA Astrophysics Data System (ADS)

Eichler, C.; Petta, J. R.

2018-06-01

We realize a superconducting circuit analog of the generic cavity-optomechanical Hamiltonian by longitudinally coupling two superconducting resonators, which are an order of magnitude different in frequency. We achieve longitudinal coupling by embedding a superconducting quantum interference device into a high frequency resonator, making its resonance frequency depend on the zero point current fluctuations of a nearby low frequency L C resonator. By applying sideband drive fields we enhance the intrinsic coupling strength of about 15 kHz up to 280 kHz by controlling the amplitude of the drive field. Our results pave the way towards the exploration of optomechanical effects in a fully superconducting platform and could enable quantum optics experiments with photons in the yet unexplored radio frequency band.

Realizing a Circuit Analog of an Optomechanical System with Longitudinally Coupled Superconducting Resonators.

PubMed

Eichler, C; Petta, J R

2018-06-01

We realize a superconducting circuit analog of the generic cavity-optomechanical Hamiltonian by longitudinally coupling two superconducting resonators, which are an order of magnitude different in frequency. We achieve longitudinal coupling by embedding a superconducting quantum interference device into a high frequency resonator, making its resonance frequency depend on the zero point current fluctuations of a nearby low frequency LC resonator. By applying sideband drive fields we enhance the intrinsic coupling strength of about 15 kHz up to 280 kHz by controlling the amplitude of the drive field. Our results pave the way towards the exploration of optomechanical effects in a fully superconducting platform and could enable quantum optics experiments with photons in the yet unexplored radio frequency band.

Flexible single-crystal silicon nanomembrane photonic crystal cavity.

PubMed

Xu, Xiaochuan; Subbaraman, Harish; Chakravarty, Swapnajit; Hosseini, Amir; Covey, John; Yu, Yalin; Kwong, David; Zhang, Yang; Lai, Wei-Cheng; Zou, Yi; Lu, Nanshu; Chen, Ray T

2014-12-23

Flexible inorganic electronic devices promise numerous applications, especially in fields that could not be covered satisfactorily by conventional rigid devices. Benefits on a similar scale are also foreseeable for silicon photonic components. However, the difficulty in transferring intricate silicon photonic devices has deterred widespread development. In this paper, we demonstrate a flexible single-crystal silicon nanomembrane photonic crystal microcavity through a bonding and substrate removal approach. The transferred cavity shows a quality factor of 2.2×10(4) and could be bent to a curvature of 5 mm radius without deteriorating the performance compared to its counterparts on rigid substrates. A thorough characterization of the device reveals that the resonant wavelength is a linear function of the bending-induced strain. The device also shows a curvature-independent sensitivity to the ambient index variation.

Enhancing the Bandwidth of Gravitational-Wave Detectors with Unstable Optomechanical Filters

NASA Astrophysics Data System (ADS)

Miao, Haixing; Ma, Yiqiu; Zhao, Chunnong; Chen, Yanbei

2015-11-01

Advanced interferometric gravitational-wave detectors use optical cavities to resonantly enhance their shot-noise-limited sensitivity. Because of positive dispersion of these cavities—signals at different frequencies pick up different phases, there is a tradeoff between the detector bandwidth and peak sensitivity, which is a universal feature for quantum measurement devices having resonant cavities. We consider embedding an active unstable filter inside the interferometer to compensate the phase, and using feedback control to stabilize the entire system. We show that this scheme in principle can enhance the bandwidth without sacrificing the peak sensitivity. However, the unstable filter under our current consideration is a cavity-assisted optomechanical device operating in the instability regime, and the thermal fluctuation of the mechanical oscillator puts a very stringent requirement on the environmental temperature and the mechanical quality factor.

Controlled Electromagnetically Induced Transparency and Fano Resonances in Hybrid BEC-Optomechanics

PubMed Central

Yasir, Kashif Ammar; Liu, Wu-Ming

2016-01-01

Cavity-optomechanics, a tool to manipulate mechanical effects of light to couple optical field with other physical objects, is the subject of increasing investigations, especially with regards to electromagnetically induced transparency (EIT). EIT, a result of Fano interference among different atomic transition levels, has acquired a significant importance in many areas of physics, such as atomic physics and quantum optics. However, controllability of such multi-dimensional systems has remained a crucial issue. In this report, we investigate the controllability of EIT and Fano resonances in hybrid optomechanical system composed of cigar-shaped Bose-Einstein condensate (BEC), trapped inside high-finesse Fabry-Pérot cavity with one vibrational mirror, driven by a single mode optical field and a transverse pump field. The transverse field is used to control the phenomenon of EIT. It is detected that the strength of transverse field is not only efficiently amplifying or attenuating out-going optical mode but also providing an opportunity to enhance the strength of Fano-interactions which leads to the amplification of EIT-window. To observe these phenomena in laboratory, we suggest a certain set of experimental parameters. The results provide a route for tunable manipulation of optical phenomena, like EIT, which could be a significant step in quantum engineering. PMID:26955789

Cavity Opto-Mechanics using an Optically Levitated Nanosphere

DTIC Science & Technology

2010-01-19

curve ) as a function of cavity finesseF≡ πc∕κL, assuming negligible gas collisions and subject to the constraints 2ζ, Ωm∕κ, Ωm∕ωm < 1∕2 and optimized...over detuning δ2. For low cavity fi- nesse the cooling is nearly limited by sideband resolution ( ~nf ;min, red curve ), and the ground-state regime hnf i...input light for each of the two systems (denoted A, B), given by X ðjÞþ;in ¼ Figure 2. A) Mean phonon number hnf i (black curve ) versus cavity

Multi-dimensional single-spin nano-optomechanics with a levitated nanodiamond

NASA Astrophysics Data System (ADS)

Neukirch, Levi P.; von Haartman, Eva; Rosenholm, Jessica M.; Nick Vamivakas, A.

2015-10-01

Considerable advances made in the development of nanomechanical and nano-optomechanical devices have enabled the observation of quantum effects, improved sensitivity to minute forces, and provided avenues to probe fundamental physics at the nanoscale. Concurrently, solid-state quantum emitters with optically accessible spin degrees of freedom have been pursued in applications ranging from quantum information science to nanoscale sensing. Here, we demonstrate a hybrid nano-optomechanical system composed of a nanodiamond (containing a single nitrogen-vacancy centre) that is levitated in an optical dipole trap. The mechanical state of the diamond is controlled by modulation of the optical trapping potential. We demonstrate the ability to imprint the multi-dimensional mechanical motion of the cavity-free mechanical oscillator into the nitrogen-vacancy centre fluorescence and manipulate the mechanical system's intrinsic spin. This result represents the first step towards a hybrid quantum system based on levitating nanoparticles that simultaneously engages optical, phononic and spin degrees of freedom.

Observability of radiation-pressure shot noise in optomechanical systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boerkje, K.; Nunnenkamp, A.; Zwickl, B. M.

2010-07-15

We present a theoretical study of an experiment designed to detect radiation-pressure shot noise in an optomechanical system. Our model consists of a coherently driven optical cavity mode that is coupled to a mechanical oscillator. We examine the cross-correlation between two quadratures of the output field from the cavity. We determine under which circumstances radiation-pressure shot noise can be detected by a measurement of this cross-correlation. This is done in the general case of nonzero detuning between the frequency of the drive and the cavity resonance frequency. We study the qualitative features of the different contributions to the cross-correlator andmore » provide quantitative figures of merit for the relative importance of the radiation-pressure shot noise contribution to other contributions. We also propose a modified setup of this experiment relevant to the 'membrane-in-the-middle' geometry, which potentially can avoid the problems of static bistability and classical noise in the drive.« less

Enhancing a slow and weak optomechanical nonlinearity with delayed quantum feedback

PubMed Central

Wang, Zhaoyou; Safavi-Naeini, Amir H.

2017-01-01

A central goal of quantum optics is to generate large interactions between single photons so that one photon can strongly modify the state of another one. In cavity optomechanics, photons interact with the motional degrees of freedom of an optical resonator, for example, by imparting radiation pressure forces on a movable mirror or sensing minute fluctuations in the position of the mirror. Here, we show that the optical nonlinearity arising from these effects, typically too small to operate on single photons, can be sufficiently enhanced with feedback to generate large interactions between single photons. We propose a protocol that allows photons propagating in a waveguide to interact with each other through multiple bounces off an optomechanical system. The protocol is analysed by evolving the full many-body quantum state of the waveguide-coupled system, illustrating that large photon–photon interactions mediated by mechanical motion may be within experimental reach. PMID:28677674

Enhancing a slow and weak optomechanical nonlinearity with delayed quantum feedback

NASA Astrophysics Data System (ADS)

Wang, Zhaoyou; Safavi-Naeini, Amir H.

2017-07-01

A central goal of quantum optics is to generate large interactions between single photons so that one photon can strongly modify the state of another one. In cavity optomechanics, photons interact with the motional degrees of freedom of an optical resonator, for example, by imparting radiation pressure forces on a movable mirror or sensing minute fluctuations in the position of the mirror. Here, we show that the optical nonlinearity arising from these effects, typically too small to operate on single photons, can be sufficiently enhanced with feedback to generate large interactions between single photons. We propose a protocol that allows photons propagating in a waveguide to interact with each other through multiple bounces off an optomechanical system. The protocol is analysed by evolving the full many-body quantum state of the waveguide-coupled system, illustrating that large photon-photon interactions mediated by mechanical motion may be within experimental reach.

Design and analysis of photonic crystal coupled cavity arrays for quantum simulation

NASA Astrophysics Data System (ADS)

Majumdar, Arka; Rundquist, Armand; Bajcsy, Michal; Dasika, Vaishno D.; Bank, Seth R.; Vučković, Jelena

2012-11-01

We performed an experimental study of coupled optical cavity arrays in a photonic crystal platform. We find that the coupling between the cavities is significantly larger than the fabrication-induced disorder in the cavity frequencies. Satisfying this condition is necessary for using such cavity arrays to generate strongly correlated photons, which has potential application in the quantum simulation of many-body systems.

Normal-Mode Splitting in a Weakly Coupled Optomechanical System

NASA Astrophysics Data System (ADS)

Rossi, Massimiliano; Kralj, Nenad; Zippilli, Stefano; Natali, Riccardo; Borrielli, Antonio; Pandraud, Gregory; Serra, Enrico; Di Giuseppe, Giovanni; Vitali, David

2018-02-01

Normal-mode splitting is the most evident signature of strong coupling between two interacting subsystems. It occurs when two subsystems exchange energy between themselves faster than they dissipate it to the environment. Here we experimentally show that a weakly coupled optomechanical system at room temperature can manifest normal-mode splitting when the pump field fluctuations are antisquashed by a phase-sensitive feedback loop operating close to its instability threshold. Under these conditions the optical cavity exhibits an effectively reduced decay rate, so that the system is effectively promoted to the strong coupling regime.

Transition of lasing modes in polymeric opal photonic crystal resonating cavity.

PubMed

Shi, Lan-Ting; Zheng, Mei-Ling; Jin, Feng; Dong, Xian-Zi; Chen, Wei-Qiang; Zhao, Zhen-Sheng; Duan, Xuan-Ming

2016-06-10

We demonstrate the transition of lasing modes in the resonating cavity constructed by polystyrene opal photonic crystals and 7 wt. % tert-butyl Rhodamine B doped polymer film. Both single mode and multiple mode lasing emission are observed from the resonating cavity. The lasing threshold is determined to be 0.81  μJ/pulse for single mode lasing emission and 2.25  μJ/pulse for multiple mode lasing emission. The single mode lasing emission is attributed to photonic lasing resulting from the photonic bandgap effect of the opal photonic crystals, while the multiple mode lasing emission is assigned to random lasing due to the defects in the photonic crystals. The result would benefit the development of low threshold polymeric solid state photonic crystal lasers.

Phase control of entanglement and quantum steering in a three-mode optomechanical system

NASA Astrophysics Data System (ADS)

Sun, F. X.; Mao, D.; Dai, Y. T.; Ficek, Z.; He, Q. Y.; Gong, Q. H.

2017-12-01

The theory of phase control of coherence, entanglement and quantum steering is developed for an optomechanical system composed of a single mode cavity containing a partially transmitting dielectric membrane and driven by short laser pulses. The membrane divides the cavity into two mutually coupled optomechanical cavities resulting in an effective three-mode closed loop system, two field modes of the two cavities and a mechanical mode representing the oscillating membrane. The closed loop in the coupling creates interfering channels which depend on the relative phase of the coupling strengths of the field modes to the mechanical mode. Populations and correlations of the output modes are calculated analytically and show several interesting phase dependent effects such as reversible population transfer from one field mode to the other, creation of collective modes, and induced coherence without induced emission. We find that these effects result from perfect mutual coherence between the field modes which is preserved even if one of the modes is not populated. The inseparability criterion for the output modes is also investigated and we find that entanglement may occur only between the field modes and the mechanical mode. We show that depending on the phase, the field modes can act on the mechanical mode collectively or individually resulting, respectively, in tripartite or bipartite entanglement. In addition, we examine the phase sensitivity of quantum steering of the mechanical mode by the field modes. Deterministic phase transfer of the steering from bipartite to collective is predicted and optimum steering corresponding to perfect EPR state can be achieved. These different types of quantum steering can be distinguished experimentally by measuring the coincidence rate between two detectors adjusted to collect photons of the output cavity modes. In particular, we find that the minima of the interference pattern of the coincidence rate signal the bipartite steering

Effective bichromatic potential for ultra-high Q-factor photonic crystal slab cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alpeggiani, Filippo, E-mail: filippo.alpeggiani01@ateneopv.it; Andreani, Lucio Claudio; Gerace, Dario

2015-12-28

We introduce a confinement mechanism in photonic crystal slab cavities, which relies on the superposition of two incommensurate one-dimensional lattices in a line-defect waveguide. It is shown that the resulting photonic profile realizes an effective quasi-periodic bichromatic potential for the electromagnetic field confinement yielding extremely high quality (Q) factor nanocavities, while simultaneously keeping the mode volume close to the diffraction limit. We apply these concepts to pillar- and hole-based photonic crystal slab cavities, respectively, and a Q-factor improvement by over an order of magnitude is shown over existing designs, especially in pillar-based structures. Thanks to the generality and easy adaptationmore » of such confinement mechanism to a broad class of cavity designs and photonic lattices, this work opens interesting routes for applications where enhanced light–matter interaction in photonic crystal structures is required.« less

Porous photonic crystal external cavity laser biosensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Qinglan; Peh, Jessie; Hergenrother, Paul J.

2016-08-15

We report the design, fabrication, and testing of a photonic crystal (PC) biosensor structure that incorporates a porous high refractive index TiO{sub 2} dielectric film that enables immobilization of capture proteins within an enhanced surface-area volume that spatially overlaps with the regions of resonant electromagnetic fields where biomolecular binding can produce the greatest shifts in photonic crystal resonant wavelength. Despite the nanoscale porosity of the sensor structure, the PC slab exhibits narrowband and high efficiency resonant reflection, enabling the structure to serve as a wavelength-tunable element of an external cavity laser. In the context of sensing small molecule interactions withmore » much larger immobilized proteins, we demonstrate that the porous structure provides 3.7× larger biosensor signals than an equivalent nonporous structure, while the external cavity laser (ECL) detection method provides capability for sensing picometer-scale shifts in the PC resonant wavelength caused by small molecule binding. The porous ECL achieves a record high figure of merit for label-free optical biosensors.« less

Acousto-optic modulation and opto-acoustic gating in piezo-optomechanical circuits

PubMed Central

Balram, Krishna C.; Davanço, Marcelo I.; Ilic, B. Robert; Kyhm, Ji-Hoon; Song, Jin Dong; Srinivasan, Kartik

2017-01-01

Acoustic wave devices provide a promising chip-scale platform for efficiently coupling radio frequency (RF) and optical fields. Here, we use an integrated piezo-optomechanical circuit platform that exploits both the piezoelectric and photoelastic coupling mechanisms to link 2.4 GHz RF waves to 194 THz (1550 nm) optical waves, through coupling to propagating and localized 2.4 GHz acoustic waves. We demonstrate acousto-optic modulation, resonant in both the optical and mechanical domains, in which waveforms encoded on the RF carrier are mapped to the optical field. We also show opto-acoustic gating, in which the application of modulated optical pulses interferometrically gates the transmission of propagating acoustic pulses. The time-domain characteristics of this system under both pulsed RF and pulsed optical excitation are considered in the context of the different physical pathways involved in driving the acoustic waves, and modelled through the coupled mode equations of cavity optomechanics. PMID:28580373

Resonant spin wave excitations in a magnonic crystal cavity

NASA Astrophysics Data System (ADS)

Kumar, N.; Prabhakar, A.

2018-03-01

Spin polarized electric current, injected into permalloy (Py) through a nano contact, exerts a torque on the magnetization. The spin waves (SWs) thus excited propagate radially outward. We propose an antidot magnonic crystal (MC) with a three-hole defect (L3) around the nano contact, designed so that the frequency of the excited SWs, lies in the band gap of the MC. L3 thus acts as a resonant SW cavity. The energy in this magnonic crystal cavity can be tapped by an adjacent MC waveguide (MCW). An analysis of the simulated micromagnetic power spectrum, at the output port of the MCW reveals stable SW oscillations. The quality factor of the device, calculated using the decay method, was estimated as Q > 105 for an injected spin current density of 7 ×1012 A/m2.

Nonlinear Dynamics and Strong Cavity Cooling of Levitated Nanoparticles.

PubMed

Fonseca, P Z G; Aranas, E B; Millen, J; Monteiro, T S; Barker, P F

2016-10-21

Optomechanical systems explore and exploit the coupling between light and the mechanical motion of macroscopic matter. A nonlinear coupling offers rich new physics, in both quantum and classical regimes. We investigate a dynamic, as opposed to the usually studied static, nonlinear optomechanical system, comprising a nanosphere levitated in a hybrid electro-optical trap. The cavity offers readout of both linear-in-position and quadratic-in-position (nonlinear) light-matter coupling, while simultaneously cooling the nanosphere, for indefinite periods of time and in high vacuum. We observe the cooling dynamics via both linear and nonlinear coupling. As the background gas pressure was lowered, we observed a greater than 1000-fold reduction in temperature before temperatures fell below readout sensitivity in the present setup. This Letter opens the way to strongly coupled quantum dynamics between a cavity and a nanoparticle largely decoupled from its environment.

Nonlinear Dynamics and Strong Cavity Cooling of Levitated Nanoparticles

NASA Astrophysics Data System (ADS)

Fonseca, P. Z. G.; Aranas, E. B.; Millen, J.; Monteiro, T. S.; Barker, P. F.

2016-10-01

Optomechanical systems explore and exploit the coupling between light and the mechanical motion of macroscopic matter. A nonlinear coupling offers rich new physics, in both quantum and classical regimes. We investigate a dynamic, as opposed to the usually studied static, nonlinear optomechanical system, comprising a nanosphere levitated in a hybrid electro-optical trap. The cavity offers readout of both linear-in-position and quadratic-in-position (nonlinear) light-matter coupling, while simultaneously cooling the nanosphere, for indefinite periods of time and in high vacuum. We observe the cooling dynamics via both linear and nonlinear coupling. As the background gas pressure was lowered, we observed a greater than 1000-fold reduction in temperature before temperatures fell below readout sensitivity in the present setup. This Letter opens the way to strongly coupled quantum dynamics between a cavity and a nanoparticle largely decoupled from its environment.

Lithographic wavelength control of an external cavity laser with a silicon photonic crystal cavity-based resonant reflector.

PubMed

Liles, Alexandros A; Debnath, Kapil; O'Faolain, Liam

2016-03-01

We report the experimental demonstration of a new design for external cavity hybrid lasers consisting of a III-V semiconductor optical amplifier (SOA) with fiber reflector and a photonic crystal (PhC)-based resonant reflector on SOI. The silicon reflector is composed of an SU8 polymer bus waveguide vertically coupled to a PhC cavity and provides a wavelength-selective optical feedback to the laser cavity. This device exhibits milliwatt-level output power and side-mode suppression ratios of more than 25 dB.

Cavity-enhanced optical trapping of bacteria using a silicon photonic crystal.

PubMed

van Leest, Thijs; Caro, Jacob

2013-11-21

On-chip optical trapping and manipulation of cells based on the evanescent field of photonic structures is emerging as a promising technique, both in research and for applications in broader context. Relying on mass fabrication techniques, the involved integration of photonics and microfluidics allows control of both the flow of light and water on the scale of interest in single cell microbiology. In this paper, we demonstrate for the first time optical trapping of single bacteria (B. subtilis and E. coli) using photonic crystal cavities for local enhancement of the evanescent field, as opposed to the synthetic particles used so far. Three types of cavities (H0, H1 and L3) are studied, embedded in a planar photonic crystal and optimized for coupling to two collinear photonic crystal waveguides. The photonic crystals are fabricated on a silicon-on-insulator chip, onto which a fluidic channel is created as well. For each of the cavities, when pumped at the resonance wavelength (around 1550 nm), we clearly demonstrate optical trapping of bacteria, in spite of their low index contrast w.r.t. water. By tracking the confined Brownian motion of B. subtilis spores in the traps using recorded microscope observations, we derive strong in-plane trap stiffnesses of about 7.6 pN nm(-1) W(-1). The values found agree very well with calculations based on the Maxwell stress tensor for the force and finite-difference time-domain simulations of the fields for the fabricated cavity geometries. We envision that our lab-on-a-chip with photonic crystal traps opens up new application directions, e.g. immobilization of single bio-objects such as mammalian cells and bacteria under controlled conditions for optical microscopy studies.

Nested trampoline resonators for optomechanics

NASA Astrophysics Data System (ADS)

Weaver, M. J.; Pepper, B.; Luna, F.; Buters, F. M.; Eerkens, H. J.; Welker, G.; Perock, B.; Heeck, K.; de Man, S.; Bouwmeester, D.

2016-01-01

Two major challenges in the development of optomechanical devices are achieving a low mechanical and optical loss rate and vibration isolation from the environment. We address both issues by fabricating trampoline resonators made from low pressure chemical vapor deposition Si3N4 with a distributed Bragg reflector mirror. We design a nested double resonator structure with 80 dB of mechanical isolation from the mounting surface at the inner resonator frequency, and we demonstrate up to 45 dB of isolation at lower frequencies in agreement with the design. We reliably fabricate devices with mechanical quality factors of around 400 000 at room temperature. In addition, these devices were used to form optical cavities with finesse up to 181 000 ± 1000. These promising parameters will enable experiments in the quantum regime with macroscopic mechanical resonators.

Synchronization enhancement of indirectly coupled oscillators via periodic modulation in an optomechanical system.

PubMed

Du, Lei; Fan, Chu-Hui; Zhang, Han-Xiao; Wu, Jin-Hui

2017-11-20

We study the synchronization behaviors of two indirectly coupled mechanical oscillators of different frequencies in a doublecavity optomechanical system. It is found that quantum synchronization is roughly vanishing though classical synchronization seems rather good when each cavity mode is driven by an external field in the absence of temporal modulations. By periodically modulating cavity detunings or driving amplitudes, however, it is possible to observe greatly enhanced quantum synchronization accompanied with nearly perfect classical synchronization. The level of quantum synchronization observed here is, in particular, much higher than that for two directly coupled mechanical oscillators. Note also that the modulation on cavity detunings is more appealing than that on driving amplitudes when the robustness of quantum synchronization is examined against the bath's mean temperature or the oscillators' frequency difference.

Performance of the x-ray free-electron laser oscillator with crystal cavity

NASA Astrophysics Data System (ADS)

Lindberg, R. R.; Kim, K.-J.; Shvyd'Ko, Yu.; Fawley, W. M.

2011-01-01

Simulations of the x-ray free-electron laser (FEL) oscillator are presented that include the frequency-dependent Bragg crystal reflectivity and the transverse diffraction and focusing using the two-dimensional FEL code GINGER. A review of the physics of Bragg crystal reflectors and the x-ray FEL oscillator is made, followed by a discussion of its numerical implementation in GINGER. The simulation results for a two-crystal cavity and realistic FEL parameters indicate ˜109 photons in a nearly Fourier-limited, ps pulse. Compressing the electron beam to 100 A and 100 fs results in comparable x-ray characteristics for relaxed beam emittance, energy spread, and/or undulator parameters, albeit in a larger radiation bandwidth. Finally, preliminary simulation results indicate that the four-crystal FEL cavity can be tuned in energy over a range of a few percent.

Transient dynamics in cavity electromagnetically induced transparency with ion Coulomb crystals

NASA Astrophysics Data System (ADS)

Albert, Magnus; Dantan, Aurélien; Drewsen, Michael

2018-03-01

We experimentally investigate the transient dynamics of an optical cavity field interacting with large ion Coulomb crystals in a situation of electromagnetically induced transparency (EIT). EIT is achieved by injecting a probe field at the single photon level and a more intense control field with opposite circular polarization into the same mode of an optical cavity to couple Zeeman substates of a metastable level in ? ions. The EIT interaction dynamics are investigated both in the frequency-domain - by measuring the probe field steady state reflectivity spectrum - and in the time-domain - by measuring the progressive buildup of transparency. The experimental results are observed to be in excellent agreement with theoretical predictions taking into account the inhomogeneity of the control field in the interaction volume, and confirm the high degree of control on light-matter interaction that can be achieved with ion Coulomb crystals in optical cavities.

Triple coupling and parameter resonance in quantum optomechanics with a single atom

NASA Astrophysics Data System (ADS)

Chang, Yue; Ian, H.; Sun, C. P.

2009-11-01

We study the energy level structure and quantum dynamics for a cavity optomechanical system assisted by a single atom. It is found that a triple coupling involving a photon, a phonon and an atom cannot be described only by the quasi-orbital angular momentum at frequency resonance, there also exists the phenomenon of parameter resonance, namely, when the system parameters are matched in some way, the evolution of the end mirror of the cavity is conditioned by the dressed states of the photon-atom subsystem. The quantum decoherence due to this conditional dynamics is studied in detail. In the quasi-classical limit of very large angular momentum, this system will behave like a standard cavity-QED system described by the Jaynes-Cummings (J-C) model when the angular momentum operators are transformed to bosonic operators of a single mode. We test this observation with an experimentally accessible parameter.

Photon-phonon parametric oscillation induced by quadratic coupling in an optomechanical resonator

NASA Astrophysics Data System (ADS)

Zhang, Lin; Ji, Fengzhou; Zhang, Xu; Zhang, Weiping

2017-07-01

A direct photon-phonon parametric effect of quadratic coupling on the mean-field dynamics of an optomechanical resonator in the large-scale-movement regime is found and investigated. Under a weak pumping power, the mechanical resonator damps to a steady state with a nonlinear static response sensitively modified by the quadratic coupling. When the driving power increases beyond the static energy balance, the steady states lose their stabilities via Hopf bifurcations, and the resonator produces stable self-sustained oscillation (limit-circle behavior) of discrete energies with step-like amplitudes due to the parametric effect of quadratic coupling, which can be understood roughly by the power balance between gain and loss on the resonator. A further increase in the pumping power can induce a chaotic dynamic of the resonator via a typical routine of period-doubling bifurcation, but which can be stabilized by the parametric effect through an inversion-bifurcation process back to the limit-circle states. The bifurcation-to-inverse-bifurcation transitions are numerically verified by the maximal Lyapunov exponents of the dynamics, which indicate an efficient way of suppressing the chaotic behavior of the optomechanical resonator by quadratic coupling. Furthermore, the parametric effect of quadratic coupling on the dynamic transitions of an optomechanical resonator can be conveniently detected or traced by the output power spectrum of the cavity field.

Nested trampoline resonators for optomechanics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weaver, M. J., E-mail: mweaver@physics.ucsb.edu; Pepper, B.; Luna, F.

2016-01-18

Two major challenges in the development of optomechanical devices are achieving a low mechanical and optical loss rate and vibration isolation from the environment. We address both issues by fabricating trampoline resonators made from low pressure chemical vapor deposition Si{sub 3}N{sub 4} with a distributed Bragg reflector mirror. We design a nested double resonator structure with 80 dB of mechanical isolation from the mounting surface at the inner resonator frequency, and we demonstrate up to 45 dB of isolation at lower frequencies in agreement with the design. We reliably fabricate devices with mechanical quality factors of around 400 000 at room temperature. Inmore » addition, these devices were used to form optical cavities with finesse up to 181 000 ± 1000. These promising parameters will enable experiments in the quantum regime with macroscopic mechanical resonators.« less

Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities

PubMed Central

Reardon, Christopher Paul; Rey, Isabella H.; Welna, Karl; O'Faolain, Liam; Krauss, Thomas F.

2012-01-01

Slow light has been one of the hot topics in the photonics community in the past decade, generating great interest both from a fundamental point of view and for its considerable potential for practical applications. Slow light photonic crystal waveguides, in particular, have played a major part and have been successfully employed for delaying optical signals1-4 and the enhancement of both linear5-7 and nonlinear devices.8-11 Photonic crystal cavities achieve similar effects to that of slow light waveguides, but over a reduced band-width. These cavities offer high Q-factor/volume ratio, for the realization of optically12 and electrically13 pumped ultra-low threshold lasers and the enhancement of nonlinear effects.14-16 Furthermore, passive filters17 and modulators18-19 have been demonstrated, exhibiting ultra-narrow line-width, high free-spectral range and record values of low energy consumption. To attain these exciting results, a robust repeatable fabrication protocol must be developed. In this paper we take an in-depth look at our fabrication protocol which employs electron-beam lithography for the definition of photonic crystal patterns and uses wet and dry etching techniques. Our optimised fabrication recipe results in photonic crystals that do not suffer from vertical asymmetry and exhibit very good edge-wall roughness. We discuss the results of varying the etching parameters and the detrimental effects that they can have on a device, leading to a diagnostic route that can be taken to identify and eliminate similar issues. The key to evaluating slow light waveguides is the passive characterization of transmission and group index spectra. Various methods have been reported, most notably resolving the Fabry-Perot fringes of the transmission spectrum20-21 and interferometric techniques.22-25 Here, we describe a direct, broadband measurement technique combining spectral interferometry with Fourier transform analysis.26 Our method stands out for its simplicity and

An optomechanical model eye for ophthalmological refractive studies.

PubMed

Arianpour, Ashkan; Tremblay, Eric J; Stamenov, Igor; Ford, Joseph E; Schanzlin, David J; Lo, Yuhwa

2013-02-01

To create an accurate, low-cost optomechanical model eye for investigation of refractive errors in clinical and basic research studies. An optomechanical fluid-filled eye model with dimensions consistent with the human eye was designed and fabricated. Optical simulations were performed on the optomechanical eye model, and the quantified resolution and refractive errors were compared with the widely used Navarro eye model using the ray-tracing software ZEMAX (Radiant Zemax, Redmond, WA). The resolution of the physical optomechanical eye model was then quantified with a complementary metal-oxide semiconductor imager using the image resolution software SFR Plus (Imatest, Boulder, CO). Refractive, manufacturing, and assembling errors were also assessed. A refractive intraocular lens (IOL) and a diffractive IOL were added to the optomechanical eye model for tests and analyses of a 1951 U.S. Air Force target chart. Resolution and aberrations of the optomechanical eye model and the Navarro eye model were qualitatively similar in ZEMAX simulations. Experimental testing found that the optomechanical eye model reproduced properties pertinent to human eyes, including resolution better than 20/20 visual acuity and a decrease in resolution as the field of view increased in size. The IOLs were also integrated into the optomechanical eye model to image objects at distances of 15, 10, and 3 feet, and they indicated a resolution of 22.8 cycles per degree at 15 feet. A life-sized optomechanical eye model with the flexibility to be patient-specific was designed and constructed. The model had the resolution of a healthy human eye and recreated normal refractive errors. This model may be useful in the evaluation of IOLs for cataract surgery. Copyright 2013, SLACK Incorporated.

Electrically driven quantum light emission in electromechanically tuneable photonic crystal cavities

NASA Astrophysics Data System (ADS)

Petruzzella, M.; Pagliano, F. M.; Zobenica, Ž.; Birindelli, S.; Cotrufo, M.; van Otten, F. W. M.; van der Heijden, R. W.; Fiore, A.

2017-12-01

A single quantum dot deterministically coupled to a photonic crystal environment constitutes an indispensable elementary unit to both generate and manipulate single-photons in next-generation quantum photonic circuits. To date, the scaling of the number of these quantum nodes on a fully integrated chip has been prevented by the use of optical pumping strategies that require a bulky off-chip laser along with the lack of methods to control the energies of nano-cavities and emitters. Here, we concurrently overcome these limitations by demonstrating electrical injection of single excitonic lines within a nano-electro-mechanically tuneable photonic crystal cavity. When an electrically driven dot line is brought into resonance with a photonic crystal mode, its emission rate is enhanced. Anti-bunching experiments reveal the quantum nature of these on-demand sources emitting in the telecom range. These results represent an important step forward in the realization of integrated quantum optics experiments featuring multiple electrically triggered Purcell-enhanced single-photon sources embedded in a reconfigurable semiconductor architecture.

Optomechanical trampoline resonators.

PubMed

Kleckner, Dustin; Pepper, Brian; Jeffrey, Evan; Sonin, Petro; Thon, Susanna M; Bouwmeester, Dirk

2011-09-26

We report on the development of optomechanical "trampoline" resonators composed of a tiny SiO(2)/Ta(2)O(5) dielectric mirror on a silicon nitride micro-resonator. We observe optical finesses of up to 4 × 10(4) and mechanical quality factors as high as 9 × 10(5) in relatively massive (~100 ng) and low frequency (10-200 kHz) devices. This results in a photon-phonon coupling efficiency considerably higher than previous Fabry-Perot-type optomechanical systems. These devices are well suited to ultra-sensitive force detection, ground-state optical cooling experiments, and demonstrations of quantum dynamics for such systems. © 2011 Optical Society of America

Wavelength-controlled external-cavity laser with a silicon photonic crystal resonant reflector

NASA Astrophysics Data System (ADS)

Gonzalez-Fernandez, A. A.; Liles, Alexandros A.; Persheyev, Saydulla; Debnath, Kapil; O'Faolain, Liam

2016-03-01

We report the experimental demonstration of an alternative design of external-cavity hybrid lasers consisting of a III-V Semiconductor Optical Amplifier with fiber reflector and a Photonic Crystal (PhC) based resonant reflector on SOI. The Silicon reflector comprises a polymer (SU8) bus waveguide vertically coupled to a PhC cavity and provides a wavelength-selective optical feedback to the laser cavity. This device exhibits milliwatt-level output power and sidemode suppression ratio of more than 25 dB.

Do Optomechanical Metasurfaces Run Out of Time?

PubMed

Viaene, Sophie; Ginis, Vincent; Danckaert, Jan; Tassin, Philippe

2018-05-11

Artificially structured metasurfaces make use of specific configurations of subwavelength resonators to efficiently manipulate electromagnetic waves. Additionally, optomechanical metasurfaces have the desired property that their actual configuration may be tuned by adjusting the power of a pump beam, as resonators move to balance pump-induced electromagnetic forces with forces due to elastic filaments or substrates. Although the reconfiguration time of optomechanical metasurfaces crucially determines their performance, the transient dynamics of unit cells from one equilibrium state to another is not understood. Here, we make use of tools from nonlinear dynamics to analyze the transient dynamics of generic optomechanical metasurfaces based on a damped-resonator model with one configuration parameter. We show that the reconfiguration time of optomechanical metasurfaces is not only limited by the elastic properties of the unit cell but also by the nonlinear dependence of equilibrium states on the pump power. For example, when switching is enabled by hysteresis phenomena, the reconfiguration time is seen to increase by over an order of magnitude. To illustrate these results, we analyze the nonlinear dynamics of a bilayer cross-wire metasurface whose optical activity is tuned by an electromagnetic torque. Moreover, we provide a lower bound for the configuration time of generic optomechanical metasurfaces. This lower bound shows that optomechanical metasurfaces cannot be faster than state-of-the-art switches at reasonable powers, even at optical frequencies.

Do Optomechanical Metasurfaces Run Out of Time?

NASA Astrophysics Data System (ADS)

Viaene, Sophie; Ginis, Vincent; Danckaert, Jan; Tassin, Philippe

2018-05-01

Artificially structured metasurfaces make use of specific configurations of subwavelength resonators to efficiently manipulate electromagnetic waves. Additionally, optomechanical metasurfaces have the desired property that their actual configuration may be tuned by adjusting the power of a pump beam, as resonators move to balance pump-induced electromagnetic forces with forces due to elastic filaments or substrates. Although the reconfiguration time of optomechanical metasurfaces crucially determines their performance, the transient dynamics of unit cells from one equilibrium state to another is not understood. Here, we make use of tools from nonlinear dynamics to analyze the transient dynamics of generic optomechanical metasurfaces based on a damped-resonator model with one configuration parameter. We show that the reconfiguration time of optomechanical metasurfaces is not only limited by the elastic properties of the unit cell but also by the nonlinear dependence of equilibrium states on the pump power. For example, when switching is enabled by hysteresis phenomena, the reconfiguration time is seen to increase by over an order of magnitude. To illustrate these results, we analyze the nonlinear dynamics of a bilayer cross-wire metasurface whose optical activity is tuned by an electromagnetic torque. Moreover, we provide a lower bound for the configuration time of generic optomechanical metasurfaces. This lower bound shows that optomechanical metasurfaces cannot be faster than state-of-the-art switches at reasonable powers, even at optical frequencies.

Design of an optomechanical filter based on solid/solid phoxonic crystals

NASA Astrophysics Data System (ADS)

Moradi, Pedram; Bahrami, Ali

2018-03-01

We simulate a phoxonic crystal which shows complete phononic and TM-polarized photonic bandgaps. The constituent materials are tungsten and polymethyl methacrylate, and we obtained these bandgaps with a filling factor of only 28%, which is very compatible with the fabrication method. A cavity was then defined that selects narrow passbands of optical and elastic waves. In order to maximize the quality factor, a defect rod is added in the output waveguide. The final structure filters an optical wavelength of 840 nm (with corresponding frequency of 357 THz) and an elastic frequency of 3.6703 GHz. Simulations are done by using finite element, plane wave expansion, and finite difference time domain methods.

Electro-optic Modulation Using a DAST Single-crystal Film in a Fabry-Perot Cavity

NASA Astrophysics Data System (ADS)

Kutty, S. P.

2005-03-01

In this paper, we report a multiple-pass electro-optic modulator using a single- crystal film of 4'-dimethyamino-N-methyl-4-stilbazolium tosylate (DAST) placed inside a Fabry-Perot cavity. The single-crystal film was prepared using the modified shear method. Electro-optic modulation was achieved at 633 nm using field-induced birefringence in the cross polarized geometry including the Fabry-Perot cavity. The modulation due to the electro-optic effect was recorded as a function of phase while the phase was controlled by moving one of the mirrors in the cavity. The observed modulation was high (80 percent) for a low field (0.5V/micron) applied along the charge transfer axis on the film. Similar modulation using the Fabry-Perot cavity with a lower modulation depth was observed involving electroabsorption at 633 nm. Electroabsorption in the DAST film has been recently reported [1]. These are important results considering applications in photonics. [1] ``Electroabsorption in single-crystal film of a second-order optical material,'' R. K. Swamy, S. P. Kutty, J. Titus, S. Khatavkar, and M. Thakur, APL, Vol. 85, 4025, (2004).

Steady-state mechanical squeezing and ground-state cooling of a Duffing anharmonic oscillator in an optomechanical cavity assisted by a nonlinear medium

NASA Astrophysics Data System (ADS)

Momeni, F.; Naderi, M. H.

2018-05-01

In this paper, we study theoretically a hybrid optomechanical system consisting of a degenerate optical parametric amplifier inside a driven optical cavity with a moving end mirror which is modeled as a stiffening Duffing-like anharmonic quantum mechanical oscillator. By providing analytical expressions for the critical values of the system parameters corresponding to the emergence of the multistability behavior in the steady-state response of the system, we show that the stiffening mechanical Duffing anharmonicity reduces the width of the multistability region while the optical parametric nonlinearity can be exploited to drive the system toward the multistability region. We also show that for appropriate values of the mechanical anharmonicity strength the steady-state mechanical squeezing and the ground-state cooling of the mechanical resonator can be achieved. Moreover, we find that the presence of the nonlinear gain medium can lead to the improvement of the mechanical anharmonicity-induced cooling of the mechanical motion, as well as to the mechanical squeezing beyond the standard quantum limit of 3 dB.

Nonlinear dynamics and cavity cooling of levitated nanoparticles

NASA Astrophysics Data System (ADS)

Fonseca, P. Z. G.; Aranas, E. B.; Millen, J.; Monteiro, T. S.; Barker, P. F.

2016-09-01

We investigate a dynamic nonlinear optomechanical system, comprising a nanosphere levitated in a hybrid electro-optical trap. An optical cavity offers readout of both linear-in-position and quadratic-in-position (nonlinear) light-matter coupling, whilst simultaneously cooling the nanosphere, for indefinite periods of time and in high vacuum. Through the rich sideband structure displayed by the cavity output we can observe cooling of the linear and non-linear particle's motion. Here we present an experimental setup which allows full control over the cavity resonant frequencies, and shows cooling of the particle's motion as a function of the detuning. This work paves the way to strong-coupled quantum dynamics between a cavity and a mesoscopic object largely decoupled from its environment.

Nano-optomechanics with optically levitated nanoparticles

NASA Astrophysics Data System (ADS)

Neukirch, Levi P.; Vamivakas, A. Nick

2015-01-01

Nano-optomechanics is a vibrant area of research that continues to push the boundary of quantum science and measurement technology. Recently, it has been realised that the optical forces experienced by polarisable nanoparticles can provide a novel platform for nano-optomechanics with untethered mechanical oscillators. Remarkably, these oscillators are expected to exhibit quality factors approaching ?. The pronounced quality factors are a direct result of the mechanical oscillator being freed from a supporting substrate. This review provides an overview of the basic optical physics underpinning optical trapping and optical levitation experiments, it discusses a number of experimental approaches to optical trapping and finally outlines possible applications of this nano-optomechanics modality in hybrid quantum systems and nanoscale optical metrology.

Nanobeam Photonic Crystal Cavity Light-Emitting Diodes

DTIC Science & Technology

2011-01-01

Nanobeam photonic crystal cavity light-emitting diodes Gary Shambat,1,a) Bryan Ellis,1 Jan Petykiewicz,1 Marie A. Mayer,2 Tomas Sarmiento ,1 James...J. H. Ryou, P. B. Deotare, R. Dupuis, and M. Loncar, Appl. Phys. Lett. 97, 051104 (2010). 5Y. Gong, B. Ellis, G. Shambat, T. Sarmiento , J. S. Harris...F. Karouta, S. He, and R. W. van der Heijden, Appl. Phys. Lett. 97, 151105 (2010). 9B. Ellis, M. A. Mayer, G. Shambat, T. Sarmiento , J. Harris, E. E

Ultra-low power fiber-coupled gallium arsenide photonic crystal cavity electro-optic modulator.

PubMed

Shambat, Gary; Ellis, Bryan; Mayer, Marie A; Majumdar, Arka; Haller, Eugene E; Vučković, Jelena

2011-04-11

We demonstrate a gallium arsenide photonic crystal cavity injection-based electro-optic modulator coupled to a fiber taper waveguide. The fiber taper serves as a convenient and tunable waveguide for cavity coupling with minimal loss. Localized electrical injection of carriers into the cavity region via a laterally doped p-i-n diode combined with the small mode volume of the cavity enable ultra-low energy modulation at sub-fJ/bit levels. Speeds of up to 1 GHz are demonstrated with photoluminescence lifetime measurements revealing that the ultimate limit goes well into the tens of GHz. © 2011 Optical Society of America

Photon-phonon-photon transfer in optomechanics

PubMed Central

Rakhubovsky, Andrey A.; Filip, Radim

2017-01-01

We consider transfer of a highly nonclassical quantum state through an optomechanical system. That is we investigate a protocol consisting of sequential upload, storage and reading out of the quantum state from a mechanical mode of an optomechanical system. We show that provided the input state is in a test-bed single-photon Fock state, the Wigner function of the recovered state can have negative values at the origin, which is a manifest of nonclassicality of the quantum state of the macroscopic mechanical mode and the overall transfer protocol itself. Moreover, we prove that the recovered state is quantum non-Gaussian for wide range of setup parameters. We verify that current electromechanical and optomechanical experiments can test this complete transfer of single photon. PMID:28436461

Optomechanically induced opacity and amplification in a quadratically coupled optomechanical system

NASA Astrophysics Data System (ADS)

Si, Liu-Gang; Xiong, Hao; Zubairy, M. Suhail; Wu, Ying

2017-03-01

We analyze theoretically the features of the output field of a quadratically coupled optomechanical system, which is driven by a strong coupling field and a weak signal field, and in which the membrane (treated as a mechanical resonator) is excited by a weak coherent driving field with two-phonon resonance. We show that the system exhibits complex quantum coherent and interference effects resulting in transmission of the signal field from opacity to remarkable amplification. We also find that the total phase of the applied fields can significantly adjust the signal field's transmission spectrum. The study of the propagation of the signal field in such a quadratically coupled optomechanical system proves that the proposed device can operate as an optical transistor.

Design and analysis of photonic crystal micro-cavity based optical sensor platform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goyal, Amit Kumar, E-mail: amitgoyal.ceeri@gmail.com; Dutta, Hemant Sankar, E-mail: hemantdutta97@gmail.com; Pal, Suchandan, E-mail: spal@ceeri.ernet.in

2016-04-13

In this paper, the design of a two-dimensional photonic crystal micro-cavity based integrated-optic sensor platform is proposed. The behaviour of designed cavity is analyzed using two-dimensional Finite Difference Time Domain (FDTD) method. The structure is designed by deliberately inserting some defects in a photonic crystal waveguide structure. Proposed structure shows a quality factor (Q) of about 1e5 and the average sensitivity of 500nm/RIU in the wavelength range of 1450 – 1580 nm. Sensing technique is based on the detection of shift in upper-edge cut-off wavelength for a reference signal strength of –10 dB in accordance with the change in refractive index ofmore » analyte.« less

Lateral shearing optical gradient force in coupled nanobeam photonic crystal cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, Han; Zhang, Xingwang; Chau, Fook Siong

2016-04-25

We report the experimental observation of lateral shearing optical gradient forces in nanoelectromechanical systems (NEMS) controlled dual-coupled photonic crystal (PhC) nanobeam cavities. With an on-chip integrated NEMS actuator, the coupled cavities can be mechanically reconfigured in the lateral direction while maintaining a constant coupling gap. Shearing optical gradient forces are generated when the two cavity centers are laterally displaced. In our experiments, positive and negative lateral shearing optical forces of 0.42 nN and 0.29 nN are observed with different pumping modes. This study may broaden the potential applications of the optical gradient force in nanophotonic devices and benefit the futuremore » nanooptoelectromechanical systems.« less

On a silicon-based photonic-crystal cavity for the near-IR region: Numerical simulation and formation technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serafimovich, P. G.; Stepikhova, M. V., E-mail: mst@ipm.sci-nnov.ru; Kazanskiy, N. L.

2016-08-15

The production technology of a photonic-crystal cavity formed as a group of holes in a silicon strip waveguide by ion-beam etching is described. The parasitic effect associated with hole conicity which develops upon hole formation by the given technology is studied. Numerical simulation shows that the hole-conicity induced decrease in the cavity quality factor can be compensated with consideration for the hole volume. The influence of the waveguide thickness on the resonance wavelength and quality factor of the photonic-crystal cavity is analyzed.

Three-wavelength multiplexer/demultiplexer based on photonic crystal ring resonator and cavities

NASA Astrophysics Data System (ADS)

Zhang, Jia; Xu, Xu-Ming; He, Ling-Juan

2011-12-01

We proposed a three-wavelength multiplexer/demultiplexer based on the characteristics of resonant coupling between photonic crystal ring resonator (PCRR) and cavity. The structure composed of one PCRR and three cavities. The numerical results obtained by the finite-different time-domain (FTDT) method show that it can realize the demultiplexing of three wavelengths, i.e. 1430nm, 1490nm and 1550nm only by modulating the radius of the cavities. The designed device not only has a compact size with 12μm×11μm but also a high efficiency, may have potential applications in the integrated optics fields.

Tunable high-order-sideband generation and carrier-envelope-phase-dependent effects via microwave fields in hybrid electro-optomechanical systems

NASA Astrophysics Data System (ADS)

Si, Liu-Gang; Guo, Ling-Xia; Xiong, Hao; Wu, Ying

2018-02-01

We investigate the high-order-sideband generation (HSG) in a hybrid cavity electro-photomechanical system in which an optical cavity is driven by two optical fields (a monochromatic pump field and a nanosecond Gaussian probe pulse with huge numbers of wave cycles), and at the same time a microwave cavity is driven by a monochromatic ac voltage bias. We show that even if the input powers of two driven optical fields are comparatively low the HSG spectra can be induced and enhanced, and the sideband plateau is extended remarkably with the power of the ac voltage bias increasing. It is also shown that the driven ac voltage bias has profound effects on the carrier-envelope-phase-dependent effects of the HSG in the hybrid cavity electro-photomechanical system. Our research may provide an effective way to control the HSG of optical fields by using microwave fields in cavity optomechanics systems.

Acousto-optical interaction of surface acoustic and optical waves in a two-dimensional phoxonic crystal hetero-structure cavity.

PubMed

Ma, Tian-Xue; Zou, Kui; Wang, Yue-Sheng; Zhang, Chuanzeng; Su, Xiao-Xing

2014-11-17

Phoxonic crystal is a promising material for manipulating sound and light simultaneously. In this paper, we theoretically demonstrate the propagation of acoustic and optical waves along the truncated surface of a two-dimensional square-latticed phoxonic crystal. Further, a phoxonic crystal hetero-structure cavity is proposed, which can simultaneously confine surface acoustic and optical waves. The interface motion and photoelastic effects are taken into account in the acousto-optical coupling. The results show obvious shifts in eigenfrequencies of the photonic cavity modes induced by different phononic cavity modes. The symmetry of the phononic cavity modes plays a more important role in the single-phonon exchange process than in the case of the multi-phonon exchange. Under the same deformation, the frequency shift of the photonic transverse electric mode is larger than that of the transverse magnetic mode.

Self-consistent Maxwell-Bloch model of quantum-dot photonic-crystal-cavity lasers

NASA Astrophysics Data System (ADS)

Cartar, William; Mørk, Jesper; Hughes, Stephen

2017-08-01

We present a powerful computational approach to simulate the threshold behavior of photonic-crystal quantum-dot (QD) lasers. Using a finite-difference time-domain (FDTD) technique, Maxwell-Bloch equations representing a system of thousands of statistically independent and randomly positioned two-level emitters are solved numerically. Phenomenological pure dephasing and incoherent pumping is added to the optical Bloch equations to allow for a dynamical lasing regime, but the cavity-mediated radiative dynamics and gain coupling of each QD dipole (artificial atom) is contained self-consistently within the model. These Maxwell-Bloch equations are implemented by using Lumerical's flexible material plug-in tool, which allows a user to define additional equations of motion for the nonlinear polarization. We implement the gain ensemble within triangular-lattice photonic-crystal cavities of various length N (where N refers to the number of missing holes), and investigate the cavity mode characteristics and the threshold regime as a function of cavity length. We develop effective two-dimensional model simulations which are derived after studying the full three-dimensional passive material structures by matching the cavity quality factors and resonance properties. We also demonstrate how to obtain the correct point-dipole radiative decay rate from Fermi's golden rule, which is captured naturally by the FDTD method. Our numerical simulations predict that the pump threshold plateaus around cavity lengths greater than N =9 , which we identify as a consequence of the complex spatial dynamics and gain coupling from the inhomogeneous QD ensemble. This behavior is not expected from simple rate-equation analysis commonly adopted in the literature, but is in qualitative agreement with recent experiments. Single-mode to multimode lasing is also observed, depending on the spectral peak frequency of the QD ensemble. Using a statistical modal analysis of the average decay rates, we also

New Developments of Broadband Cavity Enhanced Spectroscopic Techniques

NASA Astrophysics Data System (ADS)

Walsh, A.; Zhao, D.; Linnartz, H.; Ubachs, W.

2013-06-01

In recent years, cavity enhanced spectroscopic techniques, such as cavity ring-down spectroscopy (CRDS), cavity enhanced absorption spectroscopy (CEAS), and broadband cavity enhanced absorption spectroscopy (BBCEAS), have been widely employed as ultra-sensitive methods for the measurement of weak absorptions and in the real-time detection of trace species. In this contribution, we introduce two new cavity enhanced spectroscopic concepts: a) Optomechanical shutter modulated BBCEAS, a variant of BBCEAS capable of measuring optical absorption in pulsed systems with typically low duty cycles. In conventional BBCEAS applications, the latter substantially reduces the signal-to-noise ratio (S/N), consequently also reducing the detection sensitivity. To overcome this, we incorporate a fast optomechanical shutter as a time gate, modulating the detection scheme of BBCEAS and increasing the effective duty cycle reaches a value close to unity. This extends the applications of BBCEAS into pulsed samples and also in time-resolved studies. b) Cavity enhanced self-absorption spectroscopy (CESAS), a new spectroscopic concept capable of studying light emitting matter (plasma, flames, combustion samples) simultaneously in absorption and emission. In CESAS, a sample (plasma, flame or combustion source) is located in an optically stable cavity consisting of two high reflectivity mirrors, and here it acts both as light source and absorbing medium. A high detection sensitivity of weak absorption is reached without the need of an external light source, such as a laser or broadband lamp. The performance is illustrated by the first CESAS result on a supersonically expanding hydrocarbon plasma. We expect CESAS to become a generally applicable analytical tool for real time and in situ diagnostics. A. Walsh, D. Zhao, W. Ubachs, H. Linnartz, J. Phys. Chem. A, {dx.doi.org/10.1021/jp310392n}, in press, 2013. A. Walsh, D. Zhao, H. Linnartz Rev. Sci. Instrum. {84}(2), 021608 2013. A. Walsh, D. Zhao

Optomechanics: Diamonds take off

NASA Astrophysics Data System (ADS)

Hammerer, Klemens; Aspelmeyer, Markus

2015-10-01

Nanodiamonds that are levitated by light and are equipped with internal spin provide a new platform for performing quantum and optomechanical experiments with massive, environmentally isolated objects.

Bulk vertical micromachining of single-crystal sapphire using inductively coupled plasma etching for x-ray resonant cavities

NASA Astrophysics Data System (ADS)

Chen, P.-C.; Lin, P.-T.; Mikolas, D. G.; Tsai, Y.-W.; Wang, Y.-L.; Fu, C.-C.; Chang, S.-L.

2015-01-01

To provide coherent x-ray sources for probing the dynamic structures of solid or liquid biological substances on the picosecond timescale, a high-aspect-ratio x-ray resonator cavity etched from a single crystal substrate with a nearly vertical sidewall structure is required. Although high-aspect-ratio resonator cavities have been produced in silicon, they suffer from unwanted multiple beam effects. However, this problem can be avoided by using the reduced symmetry of single-crystal sapphire in which x-ray cavities may produce a highly monochromatic transmitted x-ray beam. In this study, we performed nominal 100 µm deep etching and vertical sidewall profiles in single crystal sapphire using inductively coupled plasma (ICP) etching. The large depth is required to intercept a useful fraction of a stopped-down x-ray beam, as well as for beam clearance. An electroplated Ni hard mask was patterned using KMPR 1050 photoresist and contact lithography. The quality and performance of the x-ray cavity depended upon the uniformity of the cavity gap and therefore verticality of the fabricated vertical sidewall. To our knowledge, this is the first report of such deep, vertical etching of single-crystal sapphire. A gas mixture of Cl2/BCl3/Ar was used to etch the sapphire with process variables including BCl3 flow ratio and bias power. By etching for 540 min under optimal conditions, we obtained an x-ray resonant cavity with a depth of 95 µm, width of ~30 µm, gap of ~115 µm and sidewall profile internal angle of 89.5°. The results show that the etching parameters affected the quality of the vertical sidewall, which is essential for good x-ray resonant cavities.

Local modulation of double optomechanically induced transparency and amplification.

PubMed

Yang, Q; Hou, B P; Lai, D G

2017-05-01

We consider the probe absorption properties in a mechanically coupled optomechanical system in which the two coupled nanomechanical oscillators are driven by the time-dependent forces, respectively. It is found that the mechanical interaction splits the transparency window for a usual single-mode optomechanical system into two parts and then leads to appearance of the double optomechanically induced transparency. The distance between the two transparency positions (the frequency for the maximal transparency) is determined by the mechanical interaction amplitude. This can be explained by using optomechanical dressed-mode picture which is analogue to the interacting dark resonances in coherent atoms. When the mechanical resonators are driven by the external forces, the transparencies in the double-transparency spectrum can be increased into amplifications or be suppressed by tuning the amplitude of the forces. Additionally, it is shown that the double transparencies or the amplifications oscillate with the initial phases of the forces with a period of 2π. These investigations will be useful for more flexible controllability of multi-channel optical communication based on the optomechanical systems.

Quantum synchronization of chaotic oscillator behaviors among coupled BEC-optomechanical systems

NASA Astrophysics Data System (ADS)

Li, Wenlin; Li, Chong; Song, Heshan

2017-03-01

We consider and theoretically analyze a Bose-Einstein condensate (BEC) trapped inside an optomechanical system consisting of single-mode optical cavity with a moving end mirror. The BEC is formally analogous to a mirror driven by radiation pressure with strong nonlinear coupling. Such a nonlinear enhancement can make the oscillator display chaotic behavior. By establishing proper oscillator couplings, we find that this chaotic motion can be synchronized with other oscillators, even an oscillator network. We also discuss the scheme feasibility by analyzing recent experiment parameters. Our results provide a promising platform for the quantum signal transmission and quantum logic control, and they are of potential applications in quantum information processing and quantum networks.

Optomechanics in a Levitated Droplet of Superfluid Helium

NASA Astrophysics Data System (ADS)

Brown, Charles; Harris, Glen; Harris, Jack

2017-04-01

A critical issue common to all optomechanical systems is dissipative coupling to the environment, which limits the system's quantum coherence. Superfluid helium's extremely low optical and mechanical dissipation, as well as its high thermal conductivity and its ability cool itself via evaporation, makes the mostly uncharted territory of superfluid optomechanics an exciting avenue for exploring quantum effects in macroscopic objects. I will describe ongoing work that aims to exploit the unique properties of superfluid helium by constructing an optomechanical system consisting of a magnetically levitated droplet of superfluid helium., The optical whispering gallery modes (WGMs) of the droplet, as well as the mechanical oscillations of its surface, should offer exceptionally low dissipation, and should couple to each other via the usual optomechanical interactions. I will present recent progress towards this goal, and also discuss the background for this work, which includes prior demonstrations of magnetic levitation of superfluid helium, high finesse WGMs in liquid drops, and the self-cooling of helium drops in vacuum.

Torsional Optomechanics of a Levitated Nonspherical Nanoparticle

NASA Astrophysics Data System (ADS)

Hoang, Thai M.; Ma, Yue; Ahn, Jonghoon; Bang, Jaehoon; Robicheaux, F.; Yin, Zhang-Qi; Li, Tongcang

2016-09-01

An optically levitated nanoparticle in vacuum is a paradigm optomechanical system for sensing and studying macroscopic quantum mechanics. While its center-of-mass motion has been investigated intensively, its torsional vibration has only been studied theoretically in limited cases. Here we report the first experimental observation of the torsional vibration of an optically levitated nonspherical nanoparticle in vacuum. We achieve this by utilizing the coupling between the spin angular momentum of photons and the torsional vibration of a nonspherical nanoparticle whose polarizability is a tensor. The torsional vibration frequency can be 1 order of magnitude higher than its center-of-mass motion frequency, which is promising for ground state cooling. We propose a simple yet novel scheme to achieve ground state cooling of its torsional vibration with a linearly polarized Gaussian cavity mode. A levitated nonspherical nanoparticle in vacuum will also be an ultrasensitive nanoscale torsion balance with a torque detection sensitivity on the order of 10-29 N m /√{Hz } under realistic conditions.

Asymmetric light transmission based on coupling between photonic crystal waveguides and L1/L3 cavity

NASA Astrophysics Data System (ADS)

Zhang, Jinqiannan; Chai, Hongyu; Yu, Zhongyuan; Cheng, Xiang; Ye, Han; Liu, Yumin

2017-09-01

A compact design of all-optical diode with mode conversion function based on a two-dimensional photonic crystal waveguide and an L1 or L3 cavity is theoretically investigated. The proposed photonic crystal structures comprise a triangular arrangement of air holes embedded in a silicon substrate. Asymmetric light propagation is achieved via the spatial mode match/mismatch in the coupling region. The simulations show that at each cavity's resonance frequency, the transmission efficiency of the structure with the L1 and L3 cavities reach 79% and 73%, while the corresponding unidirectionalities are 46 and 37 dB, respectively. The functional frequency can be controlled by simply adjusting the radii of specific air holes in the L1 and L3 cavities. The proposed structure can be used as a frequency filter, a beam splitter and has potential applications in all-optical integrated circuits.

Bottom-up photonic crystal cavities formed by patterned III-V nanopillars.

PubMed

Scofield, Adam C; Shapiro, Joshua N; Lin, Andrew; Williams, Alex D; Wong, Ping-Show; Liang, Baolai L; Huffaker, Diana L

2011-06-08

We report on the formation and optical properties of bottom-up photonic crystal (PC) cavities formed by III-V nanopillars (NPs) via catalyst-free selective-area metal-organic chemical vapor deposition on masked GaAs substrates. This method of NP synthesis allows for precise lithographic control of NP position and diameter enabling simultaneous formation of both the photonic band gap (PBG) region and active gain region. The PBG and cavity resonance are determined by independently tuning the NP radius r, pitch a, and height h in the respective masked areas. Near-infrared emission at 970 nm is achieved from axial GaAs/InGaAs heterostructures with in situ passivation by laterally grown InGaP shells. To achieve out-of-plane optical confinement, the PC cavities are embedded in polydimethylsiloxane (PDMS) and removed from the growth substrate. Spatially and spectrally resolved 77 K photoluminescence demonstrates a strong influence of the PBG resonance on device emission. Resonant peaks are observed in the emission spectra of PC cavities embedded in PDMS.

Far-field coupling in nanobeam photonic crystal cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rousseau, Ian, E-mail: ian.rousseau@epfl.ch; Sánchez-Arribas, Irene; Carlin, Jean-François

2016-05-16

We optimized the far-field emission pattern of one-dimensional photonic crystal nanobeams by modulating the nanobeam width, forming a sidewall Bragg cross-grating far-field coupler. By setting the period of the cross-grating to twice the photonic crystal period, we showed using three-dimensional finite-difference time-domain simulations that the intensity extracted to the far-field could be improved by more than three orders of magnitude compared to the unmodified ideal cavity geometry. We then experimentally studied the evolution of the quality factor and far-field intensity as a function of cross-grating coupler amplitude. High quality factor (>4000) blue (λ = 455 nm) nanobeam photonic crystals were fabricated out ofmore » GaN thin films on silicon incorporating a single InGaN quantum well gain medium. Micro-photoluminescence spectroscopy of sets of twelve identical nanobeams revealed a nine-fold average increase in integrated far-field emission intensity and no change in average quality factor for the optimized structure compared to the unmodulated reference. These results are useful for research environments and future nanophotonic light-emitting applications where vertical in- and out-coupling of light to nanocavities is required.« less

Low-loss tunable 1D ITO-slot photonic crystal nanobeam cavity

NASA Astrophysics Data System (ADS)

Amin, Rubab; Tahersima, Mohammad H.; Ma, Zhizhen; Suer, Can; Liu, Ke; Dalir, Hamed; Sorger, Volker J.

2018-05-01

Tunable optical material properties enable novel applications in both versatile metamaterials and photonic components including optical sources and modulators. Transparent conductive oxides (TCOs) are able to highly tune their optical properties with applied bias via altering their free carrier concentration and hence plasma dispersion. The TCO material indium tin oxide (ITO) exhibits unity-strong index change and epsilon-near-zero behavior. However, with such tuning the corresponding high optical losses, originating from the fundamental Kramers–Kronig relations, result in low cavity finesse. However, achieving efficient tuning in ITO-cavities without using light–matter interaction enhancement techniques such as polaritonic modes, which are inherently lossy, is a challenge. Here we discuss a novel one-dimensional photonic crystal nanobeam cavity to deliver a cavity system offering a wide range of resonance tuning range, while preserving physical compact footprints. We show that a vertical silicon-slot waveguide incorporating an actively gated-ITO layer delivers ∼3.4 nm of tuning. By deploying distributed feedback, we are able to keep the Q-factor moderately high with tuning. Combining this with the sub-diffraction limited mode volume (0.1 (λ/2n)3) from the photonic (non-plasmonic) slot waveguide, facilitates a high Purcell factor exceeding 1000. This strong light–matter-interaction shows that reducing the mode volume of a cavity outweighs reducing the losses in diffraction limited modal cavities such as those from bulk Si3N4. These tunable cavities enable future modulators and optical sources such as tunable lasers.

Non-Markovian Effect in Optomechanical System

NASA Astrophysics Data System (ADS)

Xin, Chun Yu; Meng, Shu Sheng; Zhou, Y. H.

2018-06-01

Most studies on optomechanical systems have been performed under the Markovian approximation. In this paper, we extend the study from the Markovian to the non-Markovian regime. According to the Markovian optomechanically induced transparency (OMIT) theory in Weis et al. (Science 330, 1520, 2010), we propose the non-Markovian counterpart. We find that the non-Markovianity might give rise to negative absorption, i.e., the probe field gains from the environment. By calculating the mean position of the mechanical resonator (MR), we illustrate the effect of non-Markovianity on the dynamics of the moving mirror.

Transmission electron microscopy characterization of macromolecular domain cavities and microstructure of single-crystal calcite tooth plates of the sea urchin Lytechinus variegatus.

PubMed

Robach, J S; Stock, S R; Veis, A

2005-07-01

The calcite plates and prisms in Lytechinus variegatus teeth form a complex biocomposite and employ a myriad of strengthening and toughening strategies. These crystal elements have macromolecule-containing internal cavities that may act to prevent cleavage. Transmission electron microscopy employing a small objective aperture was used to quantify several characteristics of these cavities. Cavity diameters ranged from 10 to 225 nm, the mean cavity diameter was between 50 and 60 nm, and cavities comprised approximately 20% of the volume of the crystal. Some cavities exhibited faceting and trace analysis identified these planes as being predominately of {1014} type. Through focus series of micrographs show the cavities were homogeneously distributed throughout the foil. The electron beam decomposed a substance within cavities and this suggests that these cavities are filled with a hydrated organic phase.

Nonreciprocal frequency conversion in a multimode microwave optomechanical circuit

NASA Astrophysics Data System (ADS)

Feofanov, A. K.; Bernier, N. R.; Toth, L. D.; Koottandavida, A.; Kippenberg, T. J.

Nonreciprocal devices such as isolators, circulators, and directional amplifiers are pivotal to quantum signal processing with superconducting circuits. In the microwave domain, commercially available nonreciprocal devices are based on ferrite materials. They are barely compatible with superconducting quantum circuits, lossy, and cannot be integrated on chip. Significant potential exists for implementing non-magnetic chip-scale nonreciprocal devices using microwave optomechanical circuits. Here we demonstrate a possibility of nonreciprocal frequency conversion in a multimode microwave optomechanical circuit using solely optomechanical interaction between modes. The conversion scheme and the results reflecting the actual progress on the experimental implementation of the scheme will be presented.

Nonreciprocity and magnetic-free isolation based on optomechanical interactions

PubMed Central

Ruesink, Freek; Miri, Mohammad-Ali; Alù, Andrea; Verhagen, Ewold

2016-01-01

Nonreciprocal components, such as isolators and circulators, provide highly desirable functionalities for optical circuitry. This motivates the active investigation of mechanisms that break reciprocity, and pose alternatives to magneto-optic effects in on-chip systems. In this work, we use optomechanical interactions to strongly break reciprocity in a compact system. We derive minimal requirements to create nonreciprocity in a wide class of systems that couple two optical modes to a mechanical mode, highlighting the importance of optically biasing the modes at a controlled phase difference. We realize these principles in a silica microtoroid optomechanical resonator and use quantitative heterodyne spectroscopy to demonstrate up to 10 dB optical isolation at telecom wavelengths. We show that nonreciprocal transmission is preserved for nondegenerate modes, and demonstrate nonreciprocal parametric amplification. These results open a route to exploiting various nonreciprocal effects in optomechanical systems in different electromagnetic and mechanical frequency regimes, including optomechanical metamaterials with topologically non-trivial properties. PMID:27897165

Engineering of nonclassical motional states in optomechanical systems

NASA Astrophysics Data System (ADS)

Xu, Xun-Wei; Wang, Hui; Zhang, Jing; Liu, Yu-xi

2013-12-01

We propose to synthesize arbitrary nonclassical motional states in optomechanical systems by using sideband excitations and photon blockade. We first demonstrate that the Hamiltonian of the optomechanical systems can be reduced, in the strong single-photon optomechanical coupling regime when the photon blockade occurs, to one describing the interaction between a driven two-level trapped ion and the vibrating modes, and then show a method to generate target states by using a series of classical pulses with desired frequencies, phases, and durations. We further analyze the effect of the photon leakage, due to small anharmonicity, on the fidelity of the expected motional state, and study environment induced decoherence. Moreover, we also discuss the experimental feasibility and provide operational parameters using the possible experimental data.

1 million-Q optomechanical microdisk resonators for sensing with very large scale integration

NASA Astrophysics Data System (ADS)

Hermouet, M.; Sansa, M.; Banniard, L.; Fafin, A.; Gely, M.; Allain, P. E.; Santos, E. Gil; Favero, I.; Alava, T.; Jourdan, G.; Hentz, S.

2018-02-01

Cavity optomechanics have become a promising route towards the development of ultrasensitive sensors for a wide range of applications including mass, chemical and biological sensing. In this study, we demonstrate the potential of Very Large Scale Integration (VLSI) with state-of-the-art low-loss performance silicon optomechanical microdisks for sensing applications. We report microdisks exhibiting optical Whispering Gallery Modes (WGM) with 1 million quality factors, yielding high displacement sensitivity and strong coupling between optical WGMs and in-plane mechanical Radial Breathing Modes (RBM). Such high-Q microdisks with mechanical resonance frequencies in the 102 MHz range were fabricated on 200 mm wafers with Variable Shape Electron Beam lithography. Benefiting from ultrasensitive readout, their Brownian motion could be resolved with good Signal-to-Noise ratio at ambient pressure, as well as in liquid, despite high frequency operation and large fluidic damping: the mechanical quality factor reduced from few 103 in air to 10's in liquid, and the mechanical resonance frequency shifted down by a few percent. Proceeding one step further, we performed an all-optical operation of the resonators in air using a pump-probe scheme. Our results show our VLSI process is a viable approach for the next generation of sensors operating in vacuum, gas or liquid phase.

Resolving the mystery of milliwatt-threshold opto-mechanical self-oscillation in dual-nanoweb fiber

NASA Astrophysics Data System (ADS)

Koehler, J. R.; Noskov, R. E.; Sukhorukov, A. A.; Butsch, A.; Novoa, D.; Russell, P. St. J.

2016-08-01

It is interesting to pose the question: How best to design an optomechanical device, with no electronics, optical cavity, or laser gain, that will self-oscillate when pumped in a single pass with only a few mW of single-frequency laser power? One might begin with a mechanically resonant and highly compliant system offering very high optomechanical gain. Such a system, when pumped by single-frequency light, might self-oscillate at its resonant frequency. It is well-known, however, that this will occur only if the group velocity dispersion of the light is high enough so that phonons causing pump-to-Stokes conversion are sufficiently dissimilar to those causing pump-to-anti-Stokes conversion. Recently it was reported that two light-guiding membranes 20 μm wide, ˜500 nm thick and spaced by ˜500 nm, suspended inside a glass fiber capillary, oscillated spontaneously at its mechanical resonant frequency (˜6 MHz) when pumped with only a few mW of single-frequency light. This was surprising, since perfect Raman gain suppression would be expected. In detailed measurements, using an interferometric side-probing technique capable of resolving nanoweb movements as small as 10 pm, we map out the vibrations along the fiber and show that stimulated intermodal scattering to a higher-order optical mode frustrates gain suppression, permitting the structure to self-oscillate. A detailed theoretical analysis confirms this picture. This novel mechanism makes possible the design of single-pass optomechanical oscillators that require only a few mW of optical power, no electronics nor any optical resonator. The design could also be implemented in silicon or any other suitable material.

Q-Boosted Optomechanical Resonators

DTIC Science & Technology

2015-11-18

Devices ( ORCHID ) Lead Organization: University of California at Berkeley Project Title: Q-Boosted Optomechanical Resonators Technical...be a PDF. Please do not password protect or secure the PDF . The maximum file size for the Report Document is 50MB. 150915 UCB Nguyen ORCHID

Coupled photonic crystal micro-cavities with ultra-low threshold power for stimulated Raman scattering.

PubMed

Liu, Qiang; Ouyang, Zhengbiao; Albin, Sacharia

2011-02-28

We propose coupled cavities to realize a strong enhancement of the Raman scattering. Five sub cavities are embedded in the photonic crystals. Simulations through finite-difference time-domain (FDTD) method demonstrate that one cavity, which is used to propagate the pump beam at the optical-communication wavelength, has a Q factor as high as 
1.254×10⁸ and modal volume as small as 0.03 μm3 (0.3192(λ/n)3). These parameters result in ultra-small threshold lasing power~17.7 nW and 2.58 nW for Stokes and anti-Stokes respectively. The cavities are designed to support the required Stokes and anti-Stokes modal spacing in silicon. The proposed structure has the potential for sensor devices, especially for biological and medical diagnoses.

Photoluminescence microscopy on air-suspended carbon nanotubes coupled to photonic crystal nanobeam cavities

NASA Astrophysics Data System (ADS)

Miura, R.; Imamura, S.; Shimada, T.; Ohta, R.; Iwamoto, S.; Arakawa, Y.; Kato, Y. K.

2014-03-01

Because carbon nanotubes are room-temperature telecom-band emitters and can be grown on silicon substrates, they are ideal for coupling to silicon photonic cavities.[2,3 In particular, as-grown air-suspended carbon nanotubes show excellent optical properties, but cavity modes with large fields in the air are needed in order to achieve efficient coupling. Here we investigate individual air-suspended nanotubes coupled to photonic crystal nanobeam cavities. We utilize cavities that confine air-band modes which have large fields in the air. Dielectric mode cavities are also prepared for comparison. We fabricate the devices from silicon-on-insulator substrates by using electron beam lithography and dry etching to form the nanobeam structure. The buried oxide layer is removed by wet etching, and carbon nanotubes are grown onto the cavities by chemical vapor deposition. We perform photoluminescence imaging and excitation spectroscopy to find the positions of the nanotubes and identify their chiralities. For both types of devices, cavity modes with quality factors of ~3000 are observed within the nanotube emission peak. Work supported by SCOPE, KAKENHI, The Telecommunications Advancement Foundation, The Toyota Physical and Chemical Research Institute, Project for Developing Innovation Systems of MEXT, Japan and the Photon Frontier Network Program of MEXT, Japan.

Bidimensional nano-optomechanics and topological backaction in a non-conservative radiation force field.

PubMed

Gloppe, A; Verlot, P; Dupont-Ferrier, E; Siria, A; Poncharal, P; Bachelier, G; Vincent, P; Arcizet, O

2014-11-01

Optomechanics, which explores the fundamental coupling between light and mechanical motion, has made important advances in manipulating macroscopic mechanical oscillators down to the quantum level. However, dynamical effects related to the vectorial nature of the optomechanical interaction remain to be investigated. Here we study a nanowire with subwavelength dimensions coupled strongly to a tightly focused beam of light, enabling an ultrasensitive readout of the nanoresonator dynamics. We determine experimentally the vectorial structure of the optomechanical interaction and demonstrate that a bidimensional dynamical backaction governs the nanowire dynamics. Moreover, the spatial topology of the optomechanical interaction is responsible for novel canonical signatures of strong coupling between mechanical modes, which leads to a topological instability that underlies the non-conservative nature of the optomechanical interaction. These results have a universal character and illustrate the increased sensitivity of nanomechanical devices towards spatially varying interactions, opening fundamental perspectives in nanomechanics, optomechanics, ultrasensitive scanning force microscopy and nano-optics.

Optimal control of the power adiabatic stroke of an optomechanical heat engine.

PubMed

Bathaee, M; Bahrampour, A R

2016-08-01

We consider the power adiabatic stroke of the Otto optomechanical heat engine introduced in Phys. Rev. Lett. 112, 150602 (2014)PRLTAO0031-900710.1103/PhysRevLett.112.150602. We derive the maximum extractable work of both optomechanical normal modes in the minimum time while the system experiences quantum friction effects. We show that the total work done by the system in the power adiabatic stroke is optimized by a bang-bang control. The time duration of the power adiabatic stroke is of the order of the inverse of the effective optomechanical-coupling coefficient. The optimal phase-space trajectory of the Otto cycle for both optomechanical normal modes is also obtained.

Terahertz Sensor Using Photonic Crystal Cavity and Resonant Tunneling Diodes

NASA Astrophysics Data System (ADS)

Okamoto, Kazuma; Tsuruda, Kazuisao; Diebold, Sebastian; Hisatake, Shintaro; Fujita, Masayuki; Nagatsuma, Tadao

2017-09-01

In this paper, we report on a terahertz (THz) sensing system. Compared to previously reported systems, it has increased system sensitivity and reduced size. Both are achieved by using a photonic crystal (PC) cavity as a resonator and compact resonant tunneling diodes (RTDs) as signal source and as detector. The measured quality factor of the PC cavity is higher than 10,000, and its resonant frequency is 318 GHz. To demonstrate the operation of the refractive index sensing system, dielectric tapes of various thicknesses are attached to the PC cavity and the change in the resonator's refractive index is measured. The figure of merit of refractive index sensing using the developed system is one order higher than that of previous studies, which used metallic metamaterial resonators. The frequency of the RTD-based source can be swept from 316 to 321 GHz by varying the RTD direct current voltage. This effect is used to realize a compact frequency tunable signal source. Measurements using a commercial signal source and detector are carried out to verify the accuracy of the data obtained using RTDs as a signal source and as a detector.

Scattering-free optical levitation of a cavity mirror.

PubMed

Guccione, G; Hosseini, M; Adlong, S; Johnsson, M T; Hope, J; Buchler, B C; Lam, P K

2013-11-01

We demonstrate the feasibility of levitating a small mirror using only radiation pressure. In our scheme, the mirror is supported by a tripod where each leg of the tripod is a Fabry-Perot cavity. The macroscopic state of the mirror is coherently coupled to the supporting cavity modes allowing coherent interrogation and manipulation of the mirror motion. The proposed scheme is an extreme example of the optical spring, where a mechanical oscillator is isolated from the environment and its mechanical frequency and macroscopic state can be manipulated solely through optical fields. We model the stability of the system and find a three-dimensional lattice of trapping points where cavity resonances allow for buildup of optical field sufficient to support the weight of the mirror. Our scheme offers a unique platform for studying quantum and classical optomechanics and can potentially be used for precision gravitational field sensing and quantum state generation.

Cavity Cooling of Nanoparticles: Towards Matter-Wave experiments

NASA Astrophysics Data System (ADS)

Millen, James; Kuhn, Stefan; Arndt, Markus

2016-05-01

Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres a few hundred nanometers in size. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.

A Low-Cost Viscometer from an Opto-Mechanical Mouse

ERIC Educational Resources Information Center

Doroodmand, Mohammad Mahdi; Maleki, Norooz; Kazemi, Hojjatollah

2010-01-01

A simple, sensitive, and portable viscometer has been designed using an opto-mechanical mouse. The viscosity of a fluid is measured using the infrared light-emitting diodes and the optical diodes of an opto-mechanical mouse. These components are positioned near the top and bottom of a glass tube containing the fluid to be measured. The viscosity…

Second harmonic generation in photonic crystal cavities in (111)-oriented GaAs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buckley, Sonia, E-mail: bucklesm@stanford.edu; Radulaski, Marina; Vučković, Jelena

2013-11-18

We demonstrate second harmonic generation at telecommunications wavelengths in photonic crystal cavities in (111)-oriented GaAs. We fabricate 30 photonic crystal structures in both (111)- and (100)-oriented GaAs and observe an increase in generated second harmonic power in the (111) orientation, with the mean power increased by a factor of 3, although there is a large scatter in the measured values. We discuss possible reasons for this increase, in particular, the reduced two photon absorption for transverse electric modes in (111) orientation, as well as a potential increase due to improved mode overlap.

Hybrid photonic crystal cavity and waveguide for coupling to diamond NV-centers.

PubMed

Barclay, Paul E; Fu, Kai-Mei; Santori, Charles; Beausoleil, Raymond G

2009-06-08

A design for an ultra-high Q photonic crystal nanocavity engineered to interact with nitrogen-vacancy (NV) centers located near the surface of a single crystal diamond sample is presented. The structure is based upon a nanowire photonic crystal geometry, and consists of a patterned high refractive index thin film, such as gallium phosphide (GaP), supported by a diamond substrate. The nanocavity supports a mode with quality factor Q > 1.5 x 10(6) and mode volume V < 0.52(lambda/nGaP)(3), and promises to allow Purcell enhanced collection of spontaneous emission from an NV located more than 50 nm below the diamond surface. The nanowire photonic crystal waveguide can be used to efficiently couple light into and out of the cavity, or as an efficient broadband collector of NV phonon sideband emission. The proposed structures can be fabricated using existing materials and processing techniques.

NFIRAOS beamsplitters subsystems optomechanical design

NASA Astrophysics Data System (ADS)

Lamontagne, Frédéric; Desnoyers, Nichola; Nash, Reston; Boucher, Marc-André; Martin, Olivier; Buteau-Vaillancourt, Louis; Châteauneuf, François; Atwood, Jenny; Hill, Alexis; Byrnes, Peter W. G.; Herriot, Glen; Véran, Jean-Pierre

2016-07-01

The early-light facility adaptive optics system for the Thirty Meter Telescope (TMT) is the Narrow-Field InfraRed Adaptive Optics System (NFIRAOS). The science beam splitter changer mechanism and the visible light beam splitter are subsystems of NFIRAOS. This paper presents the opto-mechanical design of the NFIRAOS beam splitters subsystems (NBS). In addition to the modal and the structural analyses, the beam splitters surface deformations are computed considering the environmental constraints during operation. Surface deformations are fit to Zernike polynomials using SigFit software. Rigid body motion as well as residual RMS and peak-to-valley surface deformations are calculated. Finally, deformed surfaces are exported to Zemax to evaluate the transmitted and reflected wave front error. The simulation results of this integrated opto-mechanical analysis have shown compliance with all optical requirements.

Coupling of erbium dopants to yttrium orthosilicate photonic crystal cavities for on-chip optical quantum memories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyazono, Evan; Zhong, Tian; Craiciu, Ioana

Erbium dopants in crystals exhibit highly coherent optical transitions well suited for solid-state optical quantum memories operating in the telecom band. Here, we demonstrate coupling of erbium dopant ions in yttrium orthosilicate to a photonic crystal cavity fabricated directly in the host crystal using focused ion beam milling. The coupling leads to reduction of the photoluminescence lifetime and enhancement of the optical depth in microns-long devices, which will enable on-chip quantum memories.

Scalable fabrication of coupled NV center - photonic crystal cavity systems by self-aligned N ion implantation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schröder, T.; Walsh, M.; Zheng, J.

2017-04-06

Towards building large-scale integrated photonic systems for quantum information processing, spatial and spectral alignment of single quantum systems to photonic nanocavities is required. In this paper, we demonstrate spatially targeted implantation of nitrogen vacancy (NV) centers into the mode maximum of 2-d diamond photonic crystal cavities with quality factors up to 8000, achieving an average of 1.1 ± 0.2 NVs per cavity. Nearly all NV-cavity systems have significant emission intensity enhancement, reaching a cavity-fed spectrally selective intensity enhancement, F int, of up to 93. Although spatial NV-cavity overlap is nearly guaranteed within about 40 nm, spectral tuning of the NV’smore » zero-phonon-line (ZPL) is still necessary after fabrication. To demonstrate spectral control, we temperature tune a cavity into an NV ZPL, yielding F ZPL int~5 at cryogenic temperatures.« less

Vibrational states of a water molecule in a nano-cavity of beryl crystal lattice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhukova, Elena S., E-mail: zhukovaelenka@gmail.com; Gorshunov, Boris P.; 1. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart

2014-06-14

Low-energy excitations of a single water molecule are studied when confined within a nano-size cavity formed by the ionic crystal lattice. Optical spectra are measured of manganese doped beryl single crystal Mn:Be{sub 3}Al{sub 2}Si{sub 6}O{sub 18}, that contains water molecules individually isolated in 0.51 nm diameter voids within the crystal lattice. Two types of orientation are distinguished: water-I molecules have their dipole moments aligned perpendicular to the c axis and dipole moments of water-II molecules are parallel to the c-axis. The optical conductivity σ(ν) and permittivity ε{sup ′}(ν) spectra are recorded in terahertz and infrared ranges, at frequencies from severalmore » wavenumbers up to ν = 7000 cm{sup −1}, at temperatures 5–300 K and for two polarizations, when the electric vector E of the radiation is parallel and perpendicular to the c-axis. Comparative experiments on as-grown and on dehydrated samples allow to identify the spectra of σ(ν) and ε{sup ′}(ν) caused exclusively by water molecules. In the infrared range, well-known internal modes ν{sub 1}, ν{sub 2}, and ν{sub 3} of the H{sub 2}O molecule are observed for both polarizations, indicating the presence of water-I and water-II molecules in the crystal. Spectra recorded below 1000 cm{sup −1} reveal a rich set of highly anisotropic features in the low-energy response of H{sub 2}O molecule in a crystalline nano-cavity. While for E∥c only two absorption peaks are detected, at ∼90 cm{sup −1} and ∼160 cm{sup −1}, several absorption bands are discovered for E⊥c, each consisting of narrower resonances. The bands are assigned to librational (400–500 cm{sup −1}) and translational (150–200 cm{sup −1}) vibrations of water-I molecule that is weakly coupled to the nano-cavity “walls.” A model is presented that explains the “fine structure” of the bands by a splitting of the energy levels due to quantum tunneling between the minima in a six

All-optical diode structure based on asymmetrical coupling by a micro-cavity and FP cavity at two sides of photonic crystal waveguide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Bin, E-mail: liubin-d@126.com; Liu, Yun-Feng; He, Xing-Dao

2016-06-15

A high efficiency all-optical diode based on photonic crystal (PC) waveguide has been proposed and numerically investigated by finite-difference time-domain (FDTD) method. The structure is asymmetrically coupled by a micro-cavity containing nonlinear Kerr medium and a FP cavity at sides of PC waveguide. Because of interference between two cavities, Fano peak and FP peak can both appear in transmission spectra and unidirectional transmission can be achieved. The working wavelength can set between two peaks and near to the Fano peak. For forward launch with suitable light intensity, nonlinear Kerr effect of micro-cavity can been excited. It will result in redmore » shift of Fano peak and achieving forward transmission. But for backward launch, a stronger incidence light is needed to the excite Kerr effect due to the design of asymmetric structure. This design has many advantages, including high maximum transmittance, high transmittance contrast ratio, low power threshold, short response time, and ease of integration.« less

Thermo-optical dynamics in an optically pumped Photonic Crystal nano-cavity.

PubMed

Brunstein, M; Braive, R; Hostein, R; Beveratos, A; Rober-Philip, I; Sagnes, I; Karle, T J; Yacomotti, A M; Levenson, J A; Moreau, V; Tessier, G; De Wilde, Y

2009-09-14

Linear and non-linear thermo-optical dynamical regimes were investigated in a photonic crystal cavity. First, we have measured the thermal relaxation time in an InP-based nano-cavity with quantum dots in the presence of optical pumping. The experimental method presented here allows one to obtain the dynamics of temperature in a nanocavity based on reflectivity measurements of a cw probe beam coupled through an adiabatically tapered fiber. Characteristic times of 1.0+/-0.2 micros and 0.9+/-0.2 micros for the heating and the cooling processes were obtained. Finally, thermal dynamics were also investigated in a thermo-optical bistable regime. Switch-on/off times of 2 micros and 4 micros respectively were measured, which could be explained in terms of a simple non-linear dynamical representation.

Fano resonances in photonic crystal nanobeams side-coupled with nanobeam cavities

NASA Astrophysics Data System (ADS)

Meng, Zi-Ming; Liang, Anhui; Li, Zhi-Yuan

2017-05-01

Fano resonances usually arise when a narrow resonance or discrete state and a broad resonance or continuum state are coupled. In this paper, we theoretically and numerically study asymmetric Fano line shape realized in a photonic crystal nanobeam (PCN) side-coupled with a photonic crystal nanobeam cavity (PCNC). Asymmetric transmission profiles with a transmission peak and a transmission valley are obtained for a low index concentrated cavity mode. The transmission valley, associated with the destructive interference, of our PCN-PCNC structures is deeper than that of a waveguide or Fabry-Perot resonator side-coupled with a PCNC structure. Through changing the position of the photonic band gap (PBG) of the PCN, we can utilize the high or low frequency band edge modes and the Fano transmission profiles can be further controlled. The transmission spectra of our PCN-PCNC structures can be well fitted by the Fano resonance formula and agree qualitatively with the prediction made by the temporal coupled mode theory. By using the band edge modes of the PCN as the continuum state instead of a usual broad resonance, we have demonstrated a new way to generate a prominent Fano resonance. Our PCN-PCNC structures are compact and feasible to achieve large-scale high-performance integrated photonic devices, such as optical modulators or switches.

Compact optical switch based on 2D photonic crystal and magneto-optical cavity.

PubMed

Dmitriev, Victor; Kawakatsu, Marcelo N; Portela, Gianni

2013-04-01

A compact optical switch based on a 2D photonic crystal (PhC) and a magneto-optical cavity is suggested and analyzed. The cavity is coupled to two parallel and misaligned PC waveguides and operates with dipole mode. When the cavity is nonmagnetized, the dipole mode excited by a signal in the input waveguide has a node in the output waveguide. Therefore, the input signal is reflected from the cavity. This corresponds to the state off of the switch. Normal to the plane of the PhC magnetization by a dc magnetic field produces a rotation of the dipole pattern in the cavity providing equal amplitudes of the electromagnetic fields in the input and the output waveguides. This corresponds to the state on with high transmission of the input signal. Numerical calculations show that at the 1.55 μm wavelength the device has the insertion loss -0.42 dB in the on state, the isolation -19 dB in the off state and the switch off and on ratio P(on)/P(off) about 72. The frequency band at the level of -15 dB of the resonance curve in off state is about 160 GHz.

Manipulating femtosecond pulse shape using liquid crystals infiltrated one-dimensional graded index photonic crystal waveguides composed of coupled-cavities

NASA Astrophysics Data System (ADS)

Fathollahi Khalkhali, T.; Bananej, A.

2017-10-01

In this paper, we investigate the transmission of a 10-femtosecond pulse through an ordinary and graded index coupled-cavity waveguide, using finite-difference time-domain and transfer matrix method. The ordinary structure is composed of dielectric/liquid crystal layers in which four defect layers are placed symmetrically. Next, we introduce a graded structure based on the ordinary system in which dielectric refractive index slightly increases with a constant step value from the beginning to the end of the structure while liquid crystal layers are maintained unchanged. Simulation results reveal that by applying an external static electric field and controlling liquid crystal refractive index in graded structure, it is possible to transmit an ultrashort pulse with negligible distortion and attenuation.

Quantum nondemolition measurement of optical field fluctuations by optomechanical interaction

NASA Astrophysics Data System (ADS)

Pontin, A.; Bonaldi, M.; Borrielli, A.; Marconi, L.; Marino, F.; Pandraud, G.; Prodi, G. A.; Sarro, P. M.; Serra, E.; Marin, F.

2018-03-01

According to quantum mechanics, if we keep observing a continuous variable we generally disturb its evolution. For a class of observables, however, it is possible to implement a so-called quantum nondemolition measurement: by confining the perturbation to the conjugate variable, the observable is estimated with arbitrary accuracy, or prepared in a well-known state. For instance, when the light bounces on a movable mirror, its intensity is not perturbed (the effect is just seen on the phase of the radiation), but the radiation pressure allows one to trace back its fluctuations by observing the mirror motion. In this work, we implement a cavity optomechanical experiment based on an oscillating micromirror, and we measure correlations between the output light intensity fluctuations and the mirror motion. We demonstrate that the uncertainty of the former is reduced below the shot-noise level determined by the corpuscular nature of light.

Theory and modelling of light-matter interactions in photonic crystal cavity systems coupled to quantum dot ensembles

NASA Astrophysics Data System (ADS)

Cartar, William K.

Photonic crystal microcavity quantum dot lasers show promise as high quality-factor, low threshold lasers, that can be integrated on-chip, with tunable room temperature opera- tions. However, such semiconductor microcavity lasers are notoriously difficult to model in a self-consistent way and are primarily modelled by simplified rate equation approxima- tions, typically fit to experimental data, which limits investigations of their optimization and fundamental light-matter interaction processes. Moreover, simple cavity mode optical theory and rate equations have recently been shown to fail in explaining lasing threshold trends in triangular lattice photonic crystal cavities as a function of cavity size, and the potential impact of fabrication disorder is not well understood. In this thesis, we develop a simple but powerful numerical scheme for modelling the quantum dot active layer used for lasing in these photonic crystal cavity structures, as an ensemble of randomly posi- tioned artificial two-level atoms. Each two-level atom is defined by optical Bloch equations solved by a quantum master equation that includes phenomenological pure dephasing and an incoherent pump rate that effectively models a multi-level gain system. Light-matter in- teractions of both passive and lasing structures are analyzed using simulation defined tools and post-simulation Green function techniques. We implement an active layer ensemble of up to 24,000 statistically unique quantum dots in photonic crystal cavity simulations, using a self-consistent finite-difference time-domain method. This method has the distinct advantage of capturing effects such as dipole-dipole coupling and radiative decay, without the need for any phenomenological terms, since the time-domain solution self-consistently captures these effects. Our analysis demonstrates a powerful ability to connect with recent experimental trends, while remaining completely general in its set-up; for example, we do not invoke common

Cavity-enhanced Raman microscopy of individual carbon nanotubes

PubMed Central

Hümmer, Thomas; Noe, Jonathan; Hofmann, Matthias S.; Hänsch, Theodor W.; Högele, Alexander; Hunger, David

2016-01-01

Raman spectroscopy reveals chemically specific information and provides label-free insight into the molecular world. However, the signals are intrinsically weak and call for enhancement techniques. Here, we demonstrate Purcell enhancement of Raman scattering in a tunable high-finesse microcavity, and utilize it for molecular diagnostics by combined Raman and absorption imaging. Studying individual single-wall carbon nanotubes, we identify crucial structural parameters such as nanotube radius, electronic structure and extinction cross-section. We observe a 320-times enhanced Raman scattering spectral density and an effective Purcell factor of 6.2, together with a collection efficiency of 60%. Potential for significantly higher enhancement, quantitative signals, inherent spectral filtering and absence of intrinsic background in cavity-vacuum stimulated Raman scattering render the technique a promising tool for molecular imaging. Furthermore, cavity-enhanced Raman transitions involving localized excitons could potentially be used for gaining quantum control over nanomechanical motion and open a route for molecular cavity optomechanics. PMID:27402165

Controllable chaos in hybrid electro-optomechanical systems

PubMed Central

Wang, Mei; Lü, Xin-You; Ma, Jin-Yong; Xiong, Hao; Si, Liu-Gang; Wu, Ying

2016-01-01

We investigate the nonlinear dynamics of a hybrid electro-optomechanical system (EOMS) that allows us to realize the controllable opto-mechanical nonlinearity by driving the microwave LC resonator with a tunable electric field. A controllable optical chaos is realized even without changing the optical pumping. The threshold and lifetime of the chaos could be optimized by adjusting the strength, frequency, or phase of the electric field. This study provides a method of manipulating optical chaos with an electric field. It may offer the prospect of exploring the controllable chaos in on-chip optoelectronic devices and its applications in secret communication. PMID:26948505

Controllable chaos in hybrid electro-optomechanical systems.

PubMed

Wang, Mei; Lü, Xin-You; Ma, Jin-Yong; Xiong, Hao; Si, Liu-Gang; Wu, Ying

2016-03-07

We investigate the nonlinear dynamics of a hybrid electro-optomechanical system (EOMS) that allows us to realize the controllable opto-mechanical nonlinearity by driving the microwave LC resonator with a tunable electric field. A controllable optical chaos is realized even without changing the optical pumping. The threshold and lifetime of the chaos could be optimized by adjusting the strength, frequency, or phase of the electric field. This study provides a method of manipulating optical chaos with an electric field. It may offer the prospect of exploring the controllable chaos in on-chip optoelectronic devices and its applications in secret communication.

Preliminary laboratory testing on the sound absorption of coupled cavity sonic crystal

NASA Astrophysics Data System (ADS)

Kristiani, R.; Yahya, I.; Harjana; Suparmi

2016-11-01

This paper focuses on the sound absorption performance of coupled cavity sonic crystal. It constructed by a pair of a cylindrical tube with different values in diameters. A laboratory test procedure after ASTM E1050 has been conducted to measure the sound absorption of the sonic crystal elements. The test procedures were implemented to a single coupled scatterer and also to a pair of similar structure. The results showed that using the paired structure bring a better possibility for increase the sound absorption to a wider absorption range. It also bring a practical advantage for setting the local Helmholtz resonant frequency to certain intended frequency.

Tunable phonon-cavity coupling in graphene membranes.

PubMed

De Alba, R; Massel, F; Storch, I R; Abhilash, T S; Hui, A; McEuen, P L; Craighead, H G; Parpia, J M

2016-09-01

A major achievement of the past decade has been the realization of macroscopic quantum systems by exploiting the interactions between optical cavities and mechanical resonators. In these systems, phonons are coherently annihilated or created in exchange for photons. Similar phenomena have recently been observed through phonon-cavity coupling-energy exchange between the modes of a single system mediated by intrinsic material nonlinearity. This has so far been demonstrated primarily for bulk crystalline, high-quality-factor (Q > 10(5)) mechanical systems operated at cryogenic temperatures. Here, we propose graphene as an ideal candidate for the study of such nonlinear mechanics. The large elastic modulus of this material and capability for spatial symmetry breaking via electrostatic forces is expected to generate a wealth of nonlinear phenomena, including tunable intermodal coupling. We have fabricated circular graphene membranes and report strong phonon-cavity effects at room temperature, despite the modest Q factor (∼100) of this system. We observe both amplification into parametric instability (mechanical lasing) and the cooling of Brownian motion in the fundamental mode through excitation of cavity sidebands. Furthermore, we characterize the quenching of these parametric effects at large vibrational amplitudes, offering a window on the all-mechanical analogue of cavity optomechanics, where the observation of such effects has proven elusive.

Acousto-optic modulation of a photonic crystal nanocavity with Lamb waves in microwave K band

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tadesse, Semere A.; School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455; Li, Huan

2015-11-16

Integrating nanoscale electromechanical transducers and nanophotonic devices potentially can enable acousto-optic devices to reach unprecedented high frequencies and modulation efficiency. Here, we demonstrate acousto-optic modulation of a photonic crystal nanocavity using Lamb waves with frequency up to 19 GHz, reaching the microwave K band. The devices are fabricated in suspended aluminum nitride membrane. Excitation of acoustic waves is achieved with interdigital transducers with period as small as 300 nm. Confining both acoustic wave and optical wave within the thickness of the membrane leads to improved acousto-optic modulation efficiency in these devices than that obtained in previous surface acoustic wave devices. Ourmore » system demonstrates a scalable optomechanical platform where strong acousto-optic coupling between cavity-confined photons and high frequency traveling phonons can be explored.« less

Channel add-drop filter based on dual photonic crystal cavities in push-pull mode.

PubMed

Poulton, Christopher V; Zeng, Xiaoge; Wade, Mark T; Popović, Miloš A

2015-09-15

We demonstrate an add-drop filter based on a dual photonic crystal nanobeam cavity system that emulates the operation of a traveling wave resonator, and, thus, provides separation of the through and drop port transmission from the input port. The device is on a 3×3  mm chip fabricated in an advanced microelectronics silicon-on-insulator complementary metal-oxide semiconductor (SOI CMOS) process (IBM 45 nm SOI) without any foundry process modifications. The filter shows 1 dB of insertion loss in the drop port with a 3 dB bandwidth of 64 GHz, and 16 dB extinction in the through port. To the best of our knowledge, this is the first implementation of a port-separating, add-drop filter based on standing wave cavities coupled to conventional waveguides, and demonstrates a performance that suggests potential for photonic crystal devices within optical immersion lithography-based advanced CMOS electronics-photonics integration.

Present opto-mechanical design status of NFIRAOS

NASA Astrophysics Data System (ADS)

Byrnes, Peter W. G.; Atwood, Jenny; Boucher, Marc-André; Fitzsimmons, Joeleff; Hill, Alexis; Herriot, Glen; Spanò, Paolo; Szeto, Kei; Wevers, Ivan

2014-07-01

This paper describes the current opto-mechanical design of NFIRAOS (Narrow Field InfraRed Adaptive Optics System) for the Thirty Meter Telescope (TMT). The preliminary design update review for NFIRAOS was successfully held in December 2011, and incremental design progress has since occurred on several fronts. The majority of NFIRAOS is housed within an insulated and cooled enclosure, and operates at -30 C to reduce background emissivity. The cold optomechanics are attached to a space-frame structure, kinematically supported by bipods that penetrate the insulated enclosure. The bipods are attached to an exo-structure at ambient temperature, which also supports up to three client science instruments and a science calibration unit.

Einstein-Podolsky-Rosen paradox and quantum steering in a three-mode optomechanical system

NASA Astrophysics Data System (ADS)

He, Qiongyi; Ficek, Zbigniew

2014-02-01

We study multipartite entanglement, the generation of Einstein-Podolsky-Rosen (EPR) states, and quantum steering in a three-mode optomechanical system composed of an atomic ensemble located inside a single-mode cavity with a movable mirror. The cavity mode is driven by a short laser pulse, has a nonlinear parametric-type interaction with the mirror and a linear beam-splitter-type interaction with the atomic ensemble. There is no direct interaction of the mirror with the atomic ensemble. A threshold effect for the dynamics of the system is found, above which the system works as an amplifier and below which as an attenuator of the output fields. The threshold is determined by the ratio of the coupling strengths of the cavity mode to the mirror and to the atomic ensemble. It is shown that above the threshold, the system effectively behaves as a two-mode system in which a perfect bipartite EPR state can be generated, while it is impossible below the threshold. Furthermore, a fully inseparable tripartite entanglement and even further a genuine tripartite entanglement can be produced above and below the threshold. In addition, we consider quantum steering and examine the monogamy relations that quantify the amount of bipartite steering that can be shared between different modes. It is found that the mirror is more capable for steering of entanglement than the cavity mode. The two-way steering is found between the mirror and the atomic ensemble despite the fact that they are not directly coupled to each other, while it is impossible between the output of cavity mode and the ensemble which are directly coupled to each other.

Optomechanical design of TMT NFIRAOS Subsystems at INO

NASA Astrophysics Data System (ADS)

Lamontagne, Frédéric; Desnoyers, Nichola; Grenier, Martin; Cottin, Pierre; Leclerc, Mélanie; Martin, Olivier; Buteau-Vaillancourt, Louis; Boucher, Marc-André; Nash, Reston; Lardière, Olivier; Andersen, David; Atwood, Jenny; Hill, Alexis; Byrnes, Peter W. G.; Herriot, Glen; Fitzsimmons, Joeleff; Véran, Jean-Pierre

2017-08-01

The adaptive optics system for the Thirty Meter Telescope (TMT) is the Narrow-Field InfraRed Adaptive Optics System (NFIRAOS). Recently, INO has been involved in the optomechanical design of several subsystems of NFIRAOS, including the Instrument Selection Mirror (ISM), the NFIRAOS Beamsplitters (NBS), and the NFIRAOS Source Simulator system (NSS) comprising the Focal Plane Mask (FPM), the Laser Guide Star (LGS) sources, and the Natural Guide Star (NGS) sources. This paper presents an overview of these subsystems and the optomechanical design approaches used to meet the optical performance requirements under environmental constraints.

Advanced composite materials for optomechanical systems

NASA Astrophysics Data System (ADS)

Zweben, Carl

2013-09-01

Polymer matrix composites (PMCs) have been well established in optomechanical systems for several decades. The other three classes of composites; metal matrix composites (MMCs), ceramic matrix composites (CMCs), and carbon matrix composites (CAMCs) are making significant inroads. The latter include carbon/carbon (C/C) composites (CCCs). The success of composites has resulted in increasing use in consumer, industrial, scientific, and aerospace/defense optomechanical applications. Composites offer significant advantages over traditional materials, including high stiffnesses and strengths, near-zero and tailorable coefficients of thermal expansion (CTEs), tailorable thermal conductivities (from very low to over twice that of copper), and low densities. In addition, they lack beryllium's toxicity problems. Some manufacturing processes allow parts consolidation, reducing machining and joining operations. At present, PMCs are the most widely used composites. Optomechanical applications date from the 1970s. The second High Energy Astrophysical Observatory spacecraft, placed in orbit in 1978, had an ultrahigh-modulus carbon fiber-reinforced epoxy (carbon/epoxy) optical bench metering structure. Since then, fibers and matrix materials have advanced significantly, and use of carbon fiber-reinforced polymers (CFRPs) has increased steadily. Space system examples include the Hubble Space Telescope metering truss and instrument benches, Upper Atmosphere Research Satellite (UARS), James Webb Space Telescope and many others. Use has spread to airborne applications, such as SOFIA. Perhaps the most impressive CFRP applications are the fifty-four 12m and twelve 7m moveable ground-based ALMA antennas. The other three classes of composites have a number of significant advantages over PMCs, including no moisture absorption or outgassing of organic compounds. CCC and CMC components have flown on a variety of spacecraft. MMCs have been used in space, aircraft, military and industrial

Cavity Control and Cooling of Nanoparticles in High Vacuum

NASA Astrophysics Data System (ADS)

Millen, James

2016-05-01

Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres, and control the rotation of nanorods, with the potential to produce cold, aligned nanostructures. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.

Ultralow mode-volume photonic crystal nanobeam cavities for high-efficiency coupling to individual carbon nanotube emitters

PubMed Central

Miura, R.; Imamura, S.; Ohta, R.; Ishii, A.; Liu, X.; Shimada, T.; Iwamoto, S.; Arakawa, Y.; Kato, Y. K.

2014-01-01

The unique emission properties of single-walled carbon nanotubes are attractive for achieving increased functionality in integrated photonics. In addition to being room-temperature telecom-band emitters that can be directly grown on silicon, they are ideal for coupling to nanoscale photonic structures. Here we report on high-efficiency coupling of individual air-suspended carbon nanotubes to silicon photonic crystal nanobeam cavities. Photoluminescence images of dielectric- and air-mode cavities reflect their distinctly different mode profiles and show that fields in the air are important for coupling. We find that the air-mode cavities couple more efficiently, and estimated spontaneous emission coupling factors reach a value as high as 0.85. Our results demonstrate advantages of ultralow mode-volumes in air-mode cavities for coupling to low-dimensional nanoscale emitters. PMID:25420679

Observation of optomechanical buckling transitions

PubMed Central

Xu, H.; Kemiktarak, U.; Fan, J.; Ragole, S.; Lawall, J.; Taylor, J. M.

2017-01-01

Correlated phases of matter provide long-term stability for systems as diverse as solids, magnets and potential exotic quantum materials. Mechanical systems, such as buckling transition spring switches, can have engineered, stable configurations whose dependence on a control variable is reminiscent of non-equilibrium phase transitions. In hybrid optomechanical systems, light and matter are strongly coupled, allowing engineering of rapid changes in the force landscape, storing and processing information, and ultimately probing and controlling behaviour at the quantum level. Here we report the observation of first- and second-order buckling transitions between stable mechanical states in an optomechanical system, in which full control of the nature of the transition is obtained by means of the laser power and detuning. The underlying multiwell confining potential we create is highly tunable, with a sub-nanometre distance between potential wells. Our results enable new applications in photonics and information technology, and may enable explorations of quantum phase transitions and macroscopic quantum tunnelling in mechanical systems. PMID:28248293

Single-atom cavity QED and optomicromechanics

NASA Astrophysics Data System (ADS)

Wallquist, M.; Hammerer, K.; Zoller, P.; Genes, C.; Ludwig, M.; Marquardt, F.; Treutlein, P.; Ye, J.; Kimble, H. J.

2010-02-01

In a recent publication [K. Hammerer, M. Wallquist, C. Genes, M. Ludwig, F. Marquardt, P. Treutlein, P. Zoller, J. Ye, and H. J. Kimble, Phys. Rev. Lett. 103, 063005 (2009)] we have shown the possibility to achieve strong coupling of the quantized motion of a micron-sized mechanical system to the motion of a single trapped atom. In the proposed setup the coherent coupling between a SiN membrane and a single atom is mediated by the field of a high finesse cavity and can be much larger than the relevant decoherence rates. This makes the well-developed tools of cavity quantum electrodynamics with single atoms available in the realm of cavity optomechanics. In this article we elaborate on this scheme and provide detailed derivations and technical comments. Moreover, we give numerical as well as analytical results for a number of possible applications for transfer of squeezed or Fock states from atom to membrane as well as entanglement generation, taking full account of dissipation. In the limit of strong-coupling the preparation and verification of nonclassical states of a mesoscopic mechanical system is within reach.

Cavity-enhanced measurements for determining dielectric-membrane thickness and complex index of refraction.

PubMed

Stambaugh, Corey; Durand, Mathieu; Kemiktarak, Utku; Lawall, John

2014-08-01

The material properties of silicon nitride (SiN) play an important role in the performance of SiN membranes used in optomechanical applications. An optimum design of a subwavelength high-contrast grating requires accurate knowledge of the membrane thickness and index of refraction, and its performance is ultimately limited by material absorption. Here we describe a cavity-enhanced method to measure the thickness and complex index of refraction of dielectric membranes with small, but nonzero, absorption coefficients. By determining Brewster's angle and an angle at which reflection is minimized by means of destructive interference, both the real part of the index of refraction and the sample thickness can be measured. A comparison of the losses in the empty cavity and the cavity containing the dielectric sample provides a measurement of the absorption.

Cavity opto-mechanics using an optically levitated nanosphere

PubMed Central

Chang, D. E.; Regal, C. A.; Papp, S. B.; Wilson, D. J.; Ye, J.; Painter, O.; Kimble, H. J.; Zoller, P.

2010-01-01

Recently, remarkable advances have been made in coupling a number of high-Q modes of nano-mechanical systems to high-finesse optical cavities, with the goal of reaching regimes in which quantum behavior can be observed and leveraged toward new applications. To reach this regime, the coupling between these systems and their thermal environments must be minimized. Here we propose a novel approach to this problem, in which optically levitating a nano-mechanical system can greatly reduce its thermal contact, while simultaneously eliminating dissipation arising from clamping. Through the long coherence times allowed, this approach potentially opens the door to ground-state cooling and coherent manipulation of a single mesoscopic mechanical system or entanglement generation between spatially separate systems, even in room-temperature environments. As an example, we show that these goals should be achievable when the mechanical mode consists of the center-of-mass motion of a levitated nanosphere. PMID:20080573

Low index contrast heterostructure photonic crystal cavities with high quality factors and vertical radiation coupling

NASA Astrophysics Data System (ADS)

Ge, Xiaochen; Minkov, Momchil; Fan, Shanhui; Li, Xiuling; Zhou, Weidong

2018-04-01

We report here design and experimental demonstration of heterostructure photonic crystal cavities resonating near the Γ point with simultaneous strong lateral confinement and highly directional vertical radiation patterns. The lateral confinement is provided by a mode gap originating from a gradual modulation of the hole radii. High quality factor resonance is realized with a low index contrast between silicon nitride and quartz. The near surface-normal directional emission is preserved when the size of the core region is scaled down. The influence of the cavity size parameters on the resonant modes is also investigated theoretically and experimentally.

Design of nano-groove photonic crystal cavities in lithium niobate.

PubMed

Li, Yihang; Wang, Cheng; Loncar, Marko

2015-06-15

We propose a novel design of photonic-crystal nanobeam cavities in lithium niobate (LN) for both TE and TM modes, addressing problems associated with tilted sidewalls, which commonly result from dry etching. Using optimized periodical nano-groove structures, the proposed devices could achieve quality factors as high as 3.9×10(6) with a modal volume of 5.0 (λ/n)3. We also show that such a design is promising for applications in nonlinear optics by theoretically predicting the efficiencies for electro-optic modulation and second-harmonic generation. The proposed nano-groove structures and design rules could also be applied for other material platforms that possess tilted sidewalls.

Tunable single-photon multi-channel quantum router based on an optomechanical system

NASA Astrophysics Data System (ADS)

Ma, Peng-Cheng; Yan, Lei-Lei; Zhang, Jian; Chen, Gui-Bin; Li, Xiao-Wei; Zhan, You-Bang

2018-01-01

Routing of photons plays a key role in optical communication networks and quantum networks. Although the quantum routing of signals has been investigated for various systems, both in theory and experiment, the general form of a quantum router with multi-output terminals still needs to be explored. Here, we propose an experimentally accessible tunable single-photon multi-channel routing scheme using an optomechanics cavity which is Coulomb coupled to a nanomechanical resonator. The router can extract single photons from the coherent input signal and directly modulate them into three different output channels. More importantly, the two output signal frequencies can be selected by adjusting the Coulomb coupling strength. For application purposes, we justify that there is insignificant influence from the vacuum and thermal noises on the performance of the router under cryogenic conditions. Our proposal may pave a new avenue towards multi-channel routers and quantum networks.

Compact photonic crystal circulator with flat-top transmission band created by cascading magneto-optical resonance cavities.

PubMed

Wang, Qiong; Ouyang, Zhengbiao; Lin, Mi; Liu, Qiang

2015-11-20

A new type of compact three-port circulator with flat-top transmission band (FTTB) in a two-dimensional photonic crystal has been proposed, through coupling the cascaded magneto-optical resonance cavities to waveguides. The coupled-mode theory is applied to investigate the coupled structure and analyze the condition to achieve FTTB. According to the theoretical analysis, the structure is further optimized to ensure that the condition for achieving FTTB can be satisfied for both cavity-cavity coupling and cavity-waveguide coupling. Through the finite-element method, it is demonstrated that the design can realize a high quality, nonreciprocal circulating propagation of waves with an insertion loss of 0.023 dB and an isolation of 23.3 dB, covering a wide range of operation frequency. Such a wideband circulator has potential applications in large-scale integrated photonic circuits for guiding or isolating harmful optical reflections from load elements.

Exciton dynamics in a site-controlled quantum dot coupled to a photonic crystal cavity

NASA Astrophysics Data System (ADS)

Jarlov, C.; Lyasota, A.; Ferrier, L.; Gallo, P.; Dwir, B.; Rudra, A.; Kapon, E.

2015-11-01

Exciton and cavity mode (CM) dynamics in site-controlled pyramidal quantum dots (QDs), integrated with linear photonic crystal membrane cavities, are investigated for a range of temperatures and photo-excitation power levels. The absence of spurious multi-excitonic effects, normally observed in similar structures based on self-assembled QDs, permits the observation of effects intrinsic to two-level systems embedded in a solid state matrix and interacting with optical cavity modes. The coupled exciton and CM dynamics follow the same trend, indicating that the CM is fed only by the exciton transition. The Purcell reduction of the QD and CM decay times is reproduced well by a theoretical model that includes exciton linewidth broadening and temperature dependent non-radiative processes, from which we extract a Purcell factor of 17 ± 5. For excitation powers above QD saturation, we show the influence of quantum wire barrier states at short delay time, and demonstrate the absence of multiexcitonic background emission.

Zinc Sulphide Overlayer Two-Dimensional Photonic Crystal for Enhanced Extraction of Light from a Micro Cavity Light-Emitting Diode

NASA Astrophysics Data System (ADS)

Mastro, Michael A.; Kim, Chul Soo; Kim, Mijin; Caldwell, Josh; Holm, Ron T.; Vurgaftman, Igor; Kim, Jihyun; Eddy, Charles R., Jr.; Meyer, Jerry R.

2008-10-01

A two-dimensional (2D) ZnS photonic crystal was deposited on the surface of a one-dimensional (1D) III-nitride micro cavity light-emitting diode (LED), to intermix the light extraction features of both structures (1D+2D). The deposition of an ideal micro-cavity optical thickness of ≈λ/2 is impractical for III-nitride LEDs, and in realistic multi-mode devices a large fraction of the light is lost to internal refraction as guided light. Therefore, a 2D photonic crystal on the surface of the LED was used to diffract and thus redirect this guided light out of the semiconductor over several hundred microns. Additionally, the employment of a post-epitaxy ZnS 2D photonic crystal avoided the typical etching into the GaN:Mg contact layer, a procedure which can cause damage to the near surface.

Electromagnetic coupling to centimeter-scale mechanical membrane resonators via RF cylindrical cavities

NASA Astrophysics Data System (ADS)

Martinez, Luis A.; Castelli, Alessandro R.; Delmas, William; Sharping, Jay E.; Chiao, Raymond

2016-11-01

We present experimental and theoretical results for the excitation of a mechanical oscillator via radiation pressure with a room-temperature system employing a relatively low-(Q) centimeter-size mechanical oscillator coupled to a relatively low-Q standard three-dimensional radio-frequency (RF) cavity resonator. We describe the forces giving rise to optomechanical coupling using the Maxwell stress tensor and show that nanometer-scale displacements are possible and experimentally observable. The experimental system is composed of a 35 mm diameter silicon nitride membrane sputtered with a 300 nm gold conducting film and attached to the end of a RF copper cylindrical cavity. The RF cavity is operated in its {{TE}}011 mode and amplitude modulated on resonance with the fundamental drum modes of the membrane. Membrane motion is monitored using an unbalanced, non-zero optical path difference, optically filtered Michelson interferometer capable of measuring sub-nanometer displacements.

Optomechanical stability design of space optical mapping camera

NASA Astrophysics Data System (ADS)

Li, Fuqiang; Cai, Weijun; Zhang, Fengqin; Li, Na; Fan, Junjie

2018-01-01

According to the interior orientation elements and imaging quality requirements of mapping application to mapping camera and combined with off-axis three-mirror anastigmat(TMA) system, high optomechanical stability design of a space optical mapping camera is introduced in this paper. The configuration is a coaxial TMA system used in off-axis situation. Firstly, the overall optical arrangement is described., and an overview of the optomechanical packaging is provided. Zerodurglass, carbon fiber composite and carbon-fiber reinforced silicon carbon (C/SiC) are widely used in the optomechanical structure, because their low coefficient of thermal expansion (CTE) can reduce the thermal sensitivity of the mirrors and focal plane. Flexible and unloading support are used in reflector and camera supporting structure. Epoxy structural adhesives is used for bonding optics to metal structure is also introduced in this paper. The primary mirror is mounted by means of three-point ball joint flexures system, which is attach to the back of the mirror. Then, In order to predict flexural displacements due to gravity, static finite element analysis (FEA) is performed on the primary mirror. The optical performance peak-to-valley (PV) and root-mean-square (RMS) wavefront errors are detected before and after assemble. Also, the dynamic finite element analysis(FEA) of the whole optical arrangement is carried out as to investigate the performance of optomechanical. Finally, in order to evaluate the stability of the design, the thermal vacuum test and vibration test are carried out and the Modulation Transfer Function (MTF) and elements of interior orientation are presented as the evaluation index. Before and after the thermal vacuum test and vibration test, the MTF, focal distance and position of the principal point of optical system are measured and the result is as expected.

An intra-cavity pumped dual-wavelength laser operating at 946 nm and 1064 nm with Nd:YAG  +  Nd:YVO4 crystals

NASA Astrophysics Data System (ADS)

He-Dong, Xiao; Yuan, Dong; Yu, Liu; Shu-Tao, Li; Yong-Ji, Yu; Guang-Yong, Jin

2016-09-01

We adopt a compact intra-cavity pumped structure of Nd:YAG and Nd:YVO4 crystals to develop an efficient dual-wavelength laser that operates at 946 nm and 1064 nm. A 808 nm laser diode is used to pump the Nd:YAG crystal, which emits at 946 nm, and the Nd:YVO4 crystal, which emits at 1064 nm, is intra-cavity pumped at 946 nm. In order to avoid unnecessary pump light passing though the Nd:YAG crystal, reaching the Nd:YVO4 crystal and having an impact on the cavity pump, the two crystals are placed as far from one another as possible in this experiment. The output power at 1064 nm can be adjusted from 1 W-2.9 W by varying the separation between the two crystals. A total output power of 4 W at the dual-wavelengths is achieved at an incident pump power of 30.5 W, where the individual output powers for the 946 nm and 1064 nm emissions are 1.1 W and 2.9 W, respectively.

Auxiliary-cavity-assisted ground-state cooling of an optically levitated nanosphere in the unresolved-sideband regime

NASA Astrophysics Data System (ADS)

Feng, Jin-Shan; Tan, Lei; Gu, Huai-Qiang; Liu, Wu-Ming

2017-12-01

We theoretically analyze the ground-state cooling of an optically levitated nanosphere in the unresolved-sideband regime by introducing a coupled high-quality-factor cavity. On account of the quantum interference stemming from the presence of the coupled cavity, the spectral density of the optical force exerting on the nanosphere gets changed and then the symmetry between the heating and the cooling processes is broken. Through adjusting the detuning of a strong-dissipative cavity mode, one obtains an enhanced net cooling rate for the nanosphere. It is illustrated that the ground-state cooling can be realized in the unresolved sideband regime even if the effective optomechanical coupling is weaker than the frequency of the nanosphere, which can be understood by the picture that the effective interplay of the nanosphere and the auxiliary cavity mode brings the system back to an effective resolved regime. Besides, the coupled cavity refines the dynamical stability of the system.

Optical bistability and second-harmonic generation in thin film coupled cavity photonic crystal structures

NASA Astrophysics Data System (ADS)

Diao, Liyong

This thesis deals with design, fabrication and modeling of bistable and multi-stable switching dynamics and second-harmonic generation in two groups of thin film coupled cavity photonic crystal structures. The first component studies optical bistability and multistability in such structures. Optical bistability and multistability are modelled by a nonlinear transfer matrix method. The second component is focused on the modelling and experimental measurement of second-harmonic generation in such structures. It is found that coupled cavity structures can reduce the threshold and index change for bistable operation, but single cavity structures can do the same. However, there is a clear advantage in using coupled cavity structures for multistability in that the threshold for multistability can be reduced. Second-harmonic generation is enhanced by field localization due to the resonant effect at the fundamental wavelength in single and coupled cavity structures by simulated and measured results. The work in this thesis makes three significant contributions. First, in the successful fabrication of thin film coupled cavity structures, the simulated linear transmissions of such structures match those of the fabricated structures almost exactly. Second, the newly defined figure of merit at the maximum transmission point on the bistable curve can be used to compare the material damage tolerance to any other Kerr effect nonlinear gate. Third, the simulated second-harmonic generation agrees excellently with experimental results. More generally optical thin film fabrication has commercial applications in many industry sections, such as electronics, opto-electronics, optical coating, solar cell and MEMS.

Multimode optomechanical system in the quantum regime

NASA Astrophysics Data System (ADS)

Hvidtfelt Padkær Nielsen, William; Tsaturyan, Yeghishe; Møller, Christoffer Bo; Polzik, Eugene S.; Schliesser, Albert

2017-01-01

We realize a simple and robust optomechanical system with a multitude of long-lived (Q > 107) mechanical modes in a phononic-bandgap shielded membrane resonator. An optical mode of a compact Fabry-Perot resonator detects these modes’ motion with a measurement rate (96 kHz) that exceeds the mechanical decoherence rates already at moderate cryogenic temperatures (10 K). Reaching this quantum regime entails, inter alia, quantum measurement backaction exceeding thermal forces and thus strong optomechanical quantum correlations. In particular, we observe ponderomotive squeezing of the output light mediated by a multitude of mechanical resonator modes, with quantum noise suppression up to -2.4 dB (-3.6 dB if corrected for detection losses) and bandwidths ≲90 kHz. The multimode nature of the membrane and Fabry-Perot resonators will allow multimode entanglement involving electromagnetic, mechanical, and spin degrees of freedom.

Governing equations for 1D opto-mechanical vibrations of elastic cubical micro-resonators

NASA Astrophysics Data System (ADS)

Sobhani, Hassan; Zohrabi, Mehdi

2018-03-01

In this paper by employing the Lagrangian method, the effect of the radiation pressure on the coupling between the optical and mechanical modes in an elastic cavity is surveyed. The radiation pressure couldn't be considered as an external force because the electromagnetic waves are non-separable part of the elastic media. Due to the deformation of elastic media, the electromagnetic waves is modified as a result of the element velocity. To consider the electromagnetic evolution, it is preferred to employ the Lagrangian method instead of the second Newton's law. Here, using an elastic frame, governing equations on opto-mechanical oscillations in an elastic media are derived. In a specific case, by comparing the results to the other methods, it shown that this method is more accurate because the exchange of electromagnetic waves by regarding the movement of the elastic media due to deform is considered.

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.

Enhanced Telecom Emission from Single Group-IV Quantum Dots by Precise CMOS-Compatible Positioning in Photonic Crystal Cavities.

PubMed

Schatzl, Magdalena; Hackl, Florian; Glaser, Martin; Rauter, Patrick; Brehm, Moritz; Spindlberger, Lukas; Simbula, Angelica; Galli, Matteo; Fromherz, Thomas; Schäffler, Friedrich

2017-03-15

Efficient coupling to integrated high-quality-factor cavities is crucial for the employment of germanium quantum dot (QD) emitters in future monolithic silicon-based optoelectronic platforms. We report on strongly enhanced emission from single Ge QDs into L3 photonic crystal resonator (PCR) modes based on precise positioning of these dots at the maximum of the respective mode field energy density. Perfect site control of Ge QDs grown on prepatterned silicon-on-insulator substrates was exploited to fabricate in one processing run almost 300 PCRs containing single QDs in systematically varying positions within the cavities. Extensive photoluminescence studies on this cavity chip enable a direct evaluation of the position-dependent coupling efficiency between single dots and selected cavity modes. The experimental results demonstrate the great potential of the approach allowing CMOS-compatible parallel fabrication of arrays of spatially matched dot/cavity systems for group-IV-based data transfer or quantum optical systems in the telecom regime.

Enhanced Telecom Emission from Single Group-IV Quantum Dots by Precise CMOS-Compatible Positioning in Photonic Crystal Cavities

PubMed Central

2017-01-01

Efficient coupling to integrated high-quality-factor cavities is crucial for the employment of germanium quantum dot (QD) emitters in future monolithic silicon-based optoelectronic platforms. We report on strongly enhanced emission from single Ge QDs into L3 photonic crystal resonator (PCR) modes based on precise positioning of these dots at the maximum of the respective mode field energy density. Perfect site control of Ge QDs grown on prepatterned silicon-on-insulator substrates was exploited to fabricate in one processing run almost 300 PCRs containing single QDs in systematically varying positions within the cavities. Extensive photoluminescence studies on this cavity chip enable a direct evaluation of the position-dependent coupling efficiency between single dots and selected cavity modes. The experimental results demonstrate the great potential of the approach allowing CMOS-compatible parallel fabrication of arrays of spatially matched dot/cavity systems for group-IV-based data transfer or quantum optical systems in the telecom regime. PMID:28345012

Micro-optomechanical trampoline resonators

NASA Astrophysics Data System (ADS)

Pepper, Brian; Kleckner, Dustin; Sonin, Petro; Jeffrey, Evan; Bouwmeester, Dirk

2011-03-01

Recently, micro-optomechanical devices have been proposed for implementation of experiments ranging from non-demolition measurements of phonon number to creation of macroscopic quantum superpositions. All have strenuous requirements on optical finesse, mechanical quality factor, and temperature. We present a set of devices composed of dielectric mirrors on Si 3 N4 trampoline resonators. We describe the fabrication process and present data on finesse and quality factor. The authors gratefully acknowledge support from NSF PHY-0804177 and Marie Curie EXT-CT-2006-042580.

On-chip spectroscopy with thermally tuned high-Q photonic crystal cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liapis, Andreas C., E-mail: andreas.liapis@gmail.com; Gao, Boshen; Siddiqui, Mahmudur R.

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.

Multimode optomechanical system in the quantum regime

PubMed Central

Nielsen, William Hvidtfelt Padkær; Tsaturyan, Yeghishe; Møller, Christoffer Bo; Polzik, Eugene S.; Schliesser, Albert

2017-01-01

We realize a simple and robust optomechanical system with a multitude of long-lived (Q > 107) mechanical modes in a phononic-bandgap shielded membrane resonator. An optical mode of a compact Fabry–Perot resonator detects these modes’ motion with a measurement rate (96 kHz) that exceeds the mechanical decoherence rates already at moderate cryogenic temperatures (10 K). Reaching this quantum regime entails, inter alia, quantum measurement backaction exceeding thermal forces and thus strong optomechanical quantum correlations. In particular, we observe ponderomotive squeezing of the output light mediated by a multitude of mechanical resonator modes, with quantum noise suppression up to −2.4 dB (−3.6 dB if corrected for detection losses) and bandwidths ≲90 kHz. The multimode nature of the membrane and Fabry–Perot resonators will allow multimode entanglement involving electromagnetic, mechanical, and spin degrees of freedom. PMID:27999182

Multimode optomechanical system in the quantum regime.

PubMed

Nielsen, William Hvidtfelt Padkær; Tsaturyan, Yeghishe; Møller, Christoffer Bo; Polzik, Eugene S; Schliesser, Albert

2017-01-03

We realize a simple and robust optomechanical system with a multitude of long-lived (Q > 10 7 ) mechanical modes in a phononic-bandgap shielded membrane resonator. An optical mode of a compact Fabry-Perot resonator detects these modes' motion with a measurement rate (96 kHz) that exceeds the mechanical decoherence rates already at moderate cryogenic temperatures (10 K). Reaching this quantum regime entails, inter alia, quantum measurement backaction exceeding thermal forces and thus strong optomechanical quantum correlations. In particular, we observe ponderomotive squeezing of the output light mediated by a multitude of mechanical resonator modes, with quantum noise suppression up to -2.4 dB (-3.6 dB if corrected for detection losses) and bandwidths ≲90 kHz. The multimode nature of the membrane and Fabry-Perot resonators will allow multimode entanglement involving electromagnetic, mechanical, and spin degrees of freedom.

DBR, Sub-wavelength grating, and Photonic crystal slab Fabry-Perot cavity design using phase analysis by FDTD.

PubMed

Kim, Jae Hwan Eric; Chrostowski, Lukas; Bisaillon, Eric; Plant, David V

2007-08-06

We demonstrate a Finite-Difference Time-Domain (FDTD) phase methodology to estimate resonant wavelengths in Fabry-Perot (FP) cavity structures. We validate the phase method in a conventional Vertical-Cavity Surface-Emitting Laser (VCSEL) structure using a transfer-matrix method, and compare results with a FDTD reflectance method. We extend this approach to a Sub-Wavelength Grating (SWG) and a Photonic Crystal (Phc) slab, either of which may replace one of the Distributed Bragg Reflectors (DBRs) in the VCSEL, and predict resonant conditions with varying lithographic parameters. Finally, we compare the resonant tunabilities of three different VCSEL structures, taking quality factors into account.

Einstein-Podolsky-Rosen steering and Bell nonlocality of two macroscopic mechanical oscillators in optomechanical systems

NASA Astrophysics Data System (ADS)

Li, Jie; Zhu, Shi-Yao

2017-12-01

We investigate under which conditions quantum nonlocal manifestations such as Einstein-Podolsky-Rosen steering or Bell nonlocality can manifest themselves even at the macroscopic level of two mechanical resonators in optomechanical systems. We adopt the powerful scheme of reservoir engineering, implemented by driving a cavity mode with a properly chosen two-tone field, to prepare two mechanical oscillators in an entangled state. We show that large and robust (both one-way and two-way) steering could be achieved in the steady state with realistic parameters. We analyze the mechanism of the asymmetric nature of steering in our system of a two-mode Gaussian state. However, unlike steering, a Bell nonlocality is present under much more stringent conditions. We consider two types of measurements, displaced parity and on-off detection, respectively. We show that for both the measurements the Bell violation requires very low environmental temperature. For the parity detection, a large Bell violation is observed only in the transient state when the mechanical modes decouple from the optical mode and with extremely small cavity losses and mechanical damping. However, for the on-off detection, a moderate Bell violation is found in the steady state and is robust against cavity losses and mechanical damping. Although a Bell violation with parity detection seems extremely challenging to demonstrate experimentally, the conditions required for violating Bell inequalities with the on-off detection are much less demanding.

Nanosecond-pulse-controlled higher-order sideband comb in a GaAs optomechanical disk resonator in the non-perturbative regime

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiong, Hao, E-mail: haoxiong1217@gmail.com; Si, Liu-Gang, E-mail: siliugang@gmail.com; Lü, Xin-You

2014-10-15

We propose an interesting scheme for tunable high-order sideband comb generation by utilizing ultrastrong optomechanical interaction in a GaAs optomechanical disk resonator beyond the perturbative approximation. We analyze the nonlinear nature of the optomechanical interaction, and give a full description of the non-perturbative effects. It is shown, within the non-perturbative regime, that high-order sideband comb with large intensities can be realized and controlled in a GaAs optomechanical disk resonator with experimentally achievable system parameters, and the non-perturbative regime leads to rich and nontrivial behavior.

Infiltrated photonic crystal cavity as a highly sensitive platform for glucose concentration detection

NASA Astrophysics Data System (ADS)

Arafa, Safia; Bouchemat, Mohamed; Bouchemat, Touraya; Benmerkhi, Ahlem; Hocini, Abdesselam

2017-02-01

A Bio-sensing platform based on an infiltrated photonic crystal ring shaped holes cavity-coupled waveguide system is proposed for glucose concentration detection. Considering silicon-on-insulator (SOI) technology, it has been demonstrated that the ring shaped holes configuration provides an excellent optical confinement within the cavity region, which further enhances the light-matter interactions at the precise location of the analyte medium. Thus, the sensitivity and the quality factor (Q) can be significantly improved. The transmission characteristics of light in the biosensor under different refractive indices that correspond to the change in the analyte glucose concentration are analyzed by performing finite-difference time-domain (FDTD) simulations. Accordingly, an improved sensitivity of 462 nm/RIU and a Q factor as high as 1.11х105 have been achieved, resulting in a detection limit of 3.03х10-6 RIU. Such combination of attributes makes the designed structure a promising element for performing label-free biosensing in medical diagnosis and environmental monitoring.

Optomechanical design concept for the Giant Magellan Telescope Multi-object Astronomical and Cosmological Spectrograph (GMACS)

NASA Astrophysics Data System (ADS)

Prochaska, Travis; Sauseda, Marcus; Beck, James; Schmidt, Luke; Cook, Erika; DePoy, Darren L.; Marshall, Jennifer L.; Ribeiro, Rafael; Taylor, Keith; Jones, Damien; Froning, Cynthia; Pak, Soojong; Mendes de Oliveira, Claudia; Papovich, Casey; Ji, Tae-Geun; Lee, Hye-In

2016-08-01

We describe a preliminary conceptual optomechanical design for GMACS, a wide-field, multi-object, moderate resolution optical spectrograph for the Giant Magellan Telescope (GMT). This paper describes the details of the GMACS optomechanical conceptual design, including the requirements and considerations leading to the design, mechanisms, optical mounts, and predicted flexure performance.

New generation of one-dimensional photonic crystal cavities as robust high-efficient frequency converter

NASA Astrophysics Data System (ADS)

Parvini, T. S.; Tehranchi, M. M.; Hamidi, S. M.

2017-07-01

An effective method is proposed to design finite one-dimensional photonic crystal cavities (PhCCs) as robust high-efficient frequency converter. For this purpose, we consider two groups of PhCCs which are constructed by stacking m nonlinear (LiNbO3) and n linear (air) layers with variable thicknesses. In the first group, the number of linear layers is less than the nonlinear layers by one and in the second group by two. The conversion efficiency is calculated as a function of the arrangement and thicknesses of the linear and nonlinear layers by benefiting from nonlinear transfer matrix method. Our numerical simulations show that for each group of PhCCs, there is a structural formula by which the configurations with the highest efficiency can be constructed for any values of m and n (i.e. any number of layers). The efficient configurations are equivalent to Fabry-Pérot cavities that depend on the relationship between m and n and the mirrors in two sides of these cavities can be periodic or nonperiodic. The conversion efficiencies of these designed PhCCs are more than 5 orders of magnitude higher than the perfect ones which satisfy photonic bandgap edge and quasi-phase matching. Moreover, the results reveal that conversion efficiencies of Fabry-Pérot cavities with non-periodic mirrors are one order of magnitude higher than those with periodic mirrors. The major physical mechanisms of the enhancement are quasi-phase matching effect, cavity effect induced by dispersive mirrors, and double resonance for the pump and the harmonic fields in defect state. We believe that this method is very beneficial to the design of high-efficient compact optical frequency converters.

Stability Formulation for Integrated Opto-mechanic Phase Shifters.

PubMed

Ozer, Yigit; Kocaman, Serdar

2018-01-31

Stability of opto-mechanical phase shifters consisting of waveguides and non-signal carrying control beams is investigated thoroughly and a formula determining the physical limitations has been proposed. Suggested formulation is not only beneficial to determine physical strength of the system but also advantageous to guess the response of the output to the fabrication errors. In the iterative analysis of cantilever and double-clamped beam geometrical configurations, the stability condition is revealed under the strong inter-dependence of the system parameters such as input power, device length and waveguide separation. Numerical calculations involving effective index modifications and opto-mechanic movements show that well-known cantilever beams are unstable and inadequate to generate φ = 180° phase difference, while double-clamped beam structures can be utilized to build functional devices. Ideal operation conditions are also presented in terms of both the device durability and the controllability of phase evolution.

The two-dimensional hybrid surface plasma micro-cavity

NASA Astrophysics Data System (ADS)

Kai, Tong; Mei-yu, Wang; Fu-cheng, Wang; Jia, Guo

2018-07-01

A hybrid surface plasma micro-cavity structure with a defect cavity is formed based on the two-dimensional surface plasmon resonance photonic crystal waveguide structure. A cell defect is introduced in the centre of the photonic crystal layer to build the hybrid surface plasma micro-cavity structure. This work is numerical based on the finite-difference time-domain method. The photon energy is confined to the micro-cavity and the photon energy is strongest at the interface between the insulating layer and the metal layer. The micro-cavity structure has a very small mode volume of sub-wavelength scale in the 1550 nm communication band. The value of Q/V is up to 7132.08 λ/n-3.

Beating the Standard Sensitivity-Bandwidth Limit of Cavity-Enhanced Interferometers with Internal Squeezed-Light Generation

NASA Astrophysics Data System (ADS)

Korobko, M.; Kleybolte, L.; Ast, S.; Miao, H.; Chen, Y.; Schnabel, R.

2017-04-01

The shot-noise limited peak sensitivity of cavity-enhanced interferometric measurement devices, such as gravitational-wave detectors, can be improved by increasing the cavity finesse, even when comparing fixed intracavity light powers. For a fixed light power inside the detector, this comes at the price of a proportional reduction in the detection bandwidth. High sensitivity over a large span of signal frequencies, however, is essential for astronomical observations. It is possible to overcome this standard sensitivity-bandwidth limit using nonclassical correlations in the light field. Here, we investigate the internal squeezing approach, where the parametric amplification process creates a nonclassical correlation directly inside the interferometer cavity. We theoretically analyze the limits of the approach and measure 36% increase in the sensitivity-bandwidth product compared to the classical case. To our knowledge, this is the first experimental demonstration of an improvement in the sensitivity-bandwidth product using internal squeezing, opening the way for a new class of optomechanical force sensing devices.

High precision optomechanical assembly using threads as mechanical reference

NASA Astrophysics Data System (ADS)

Lamontagne, Frédéric; Desnoyers, Nichola; Bergeron, Guy; Cantin, Mario

2016-09-01

A convenient method to assemble optomechanical components is to use threaded interface. For example, lenses are often secured inside barrels using threaded rings. In other cases, multiple optical sub-assemblies such as lens barrels can be threaded to each other. Threads have the advantage to provide a simple assembly method, to be easy to manufacture, and to offer a compact mechanical design. On the other hand, threads are not considered to provide accurate centering between parts because of the assembly clearance between the inner and outer threads. For that reason, threads are often used in conjunction with precision cylindrical surfaces to limit the radial clearance between the parts to be centered. Therefore, tight manufacturing tolerances are needed on these pilot diameters, which affect the cost of the optical assembly. This paper presents a new optomechanical approach that uses threads as mechanical reference. This innovative method relies on geometric principles to auto-center parts to each other with a very low centering error that is usually less than 5 μm. The method allows to auto-center an optical group in a main barrel, to perform an axial adjustment of an optical group inside a main barrel, and to perform stacking of multiple barrels. In conjunction with the lens auto-centering method that also used threads as a mechanical reference, this novel solution opens new possibilities to realize a variety of different high precision optomechanical assemblies at lower cost.

Single crystal diamond membranes for nanoelectronics.

PubMed

Bray, Kerem; Kato, Hiromitsu; Previdi, Rodolfo; Sandstrom, Russell; Ganesan, Kumaravelu; Ogura, Masahiko; Makino, Toshiharu; Yamasaki, Satoshi; Magyar, Andrew P; Toth, Milos; Aharonovich, Igor

2018-02-22

Single crystal, nanoscale diamond membranes are highly sought after for a variety of applications including nanophotonics, nanoelectronics and quantum information science. However, so far, the availability of conductive diamond membranes has remained an unreachable goal. In this work we present a complete nanofabrication methodology for engineering high aspect ratio, electrically active single crystal diamond membranes. The membranes have large lateral directions, exceeding ∼500 × 500 μm 2 and are only several hundreds of nanometers thick. We further realize vertical single crystal p-n junctions made from the diamond membranes that exhibit onset voltages of ∼10 V and a current of several mA. Moreover, we deterministically introduce optically active color centers into the membranes, and demonstrate for the first time a single crystal nanoscale diamond LED. The robust and scalable approach to engineer the electrically active single crystal diamond membranes offers new pathways for advanced nanophotonic, nanoelectronic and optomechanical devices employing diamond.

High-frequency and high-quality silicon carbide optomechanical microresonators

PubMed Central

Lu, Xiyuan; Lee, Jonathan Y.; Lin, Qiang

2015-01-01

Silicon carbide (SiC) exhibits excellent material properties attractive for broad applications. We demonstrate the first SiC optomechanical microresonators that integrate high mechanical frequency, high mechanical quality, and high optical quality into a single device. The radial-breathing mechanical mode has a mechanical frequency up to 1.69 GHz with a mechanical Q around 5500 in atmosphere, which corresponds to a fm · Qm product as high as 9.47 × 1012 Hz. The strong optomechanical coupling allows us to efficiently excite and probe the coherent mechanical oscillation by optical waves. The demonstrated devices, in combination with the superior thermal property, chemical inertness, and defect characteristics of SiC, show great potential for applications in metrology, sensing, and quantum photonics, particularly in harsh environments that are challenging for other device platforms. PMID:26585637

Robust entanglement between a movable mirror and atomic ensemble and entanglement transfer in coupled optomechanical system

PubMed Central

Bai, Cheng-Hua; Wang, Dong-Yang; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

2016-01-01

We propose a scheme for the creation of robust entanglement between a movable mirror and atomic ensemble at the macroscopic level in coupled optomechanical system. We numerically simulate the degree of entanglement of the bipartite macroscopic entanglement and show that it depends on the coupling strength between the cavities and is robust with respect to the certain environment temperature. Inspiringly and surprisingly, according to the reported relation between the mechanical damping rate and the mechanical frequency of the movable mirror, the numerical simulation result shows that such bipartite macroscopic entanglement persists for environment temperature up to 170 K, which breaks the liquid nitrogen cooling and liquid helium cooling and largely lowers down the experiment cost. We also investigate the entanglement transfer based on this coupled system. The scheme can be used for the realization of quantum memories for continuous variable quantum information processing and quantum-limited displacement measurements. PMID:27624534

Cavity Enhanced Absorption Spectroscopy using a Prism Cavity and Supercontinuum Source

NASA Astrophysics Data System (ADS)

Lehmann, Kevin K.; Johnston, Paul S.

2010-03-01

The multiplex advantage of current cavity enhanced spectrometers is limited by the limited high reflectivity bandwidth of the dielectric mirrors used to construct the high finesse cavity. We report on our development of a spectrometer that uses Brewster's angle retroreflectors that is excited with supercontinuum radiation generated by a 1.06 μm pumped photonic crystal fiber, which covers the 500-1800 nm spectral range. Recent progress will be discussed including modeling of the prism cavity losses, alternative prism materials for use in the UV and mid-IR, and a new higher power source pumped by a mode-locked laser.

Electron spin control and torsional optomechanics of an optically levitated nanodiamond in vacuum

NASA Astrophysics Data System (ADS)

Li, Tongcang; Hoang, Thai; Ahn, Jonghoon; Bang, Jaehoon

Electron spins of diamond nitrogen-vacancy (NV) centers are important quantum resources for nanoscale sensing and quantum information. Combining such NV spin systems with levitated optomechanical resonators will provide a hybrid quantum system for many novel applications. Here we optically levitate a nanodiamond and demonstrate electron spin control of its built-in NV centers in vacuum. We observe that the strength of electron spin resonance (ESR) is enhanced when the air pressure is reduced. We also observe that oxygen and helium gases have different effects on both the photoluminescence and the ESR contrast of nanodiamond NV centers, indicating potential applications of NV centers in oxygen gas sensing. For spin-optomechanics, it is important to control the orientation of the nanodiamond and NV centers in a magnetic field. Recently, we have observed the angular trapping and torsional vibration of a levitated nanodiamond, which paves the way towards levitated torsional optomechanics in the quantum regime. NSF 1555035-PHY.

Characteristics of strain-sensitive photonic crystal cavities in a flexible substrate.

PubMed

No, You-Shin; Choi, Jae-Hyuck; Kim, Kyoung-Ho; Park, Hong-Gyu

2016-11-14

High-index semiconductor photonic crystal (PhC) cavities in a flexible substrate support strong and tunable optical resonances that can be used for highly sensitive and spatially localized detection of mechanical deformations in physical systems. Here, we report theoretical studies and fundamental understandings of resonant behavior of an optical mode excited in strain-sensitive rod-type PhC cavities consisting of high-index dielectric nanorods embedded in a low-index flexible polymer substrate. Using the three-dimensional finite-difference time-domain simulation method, we calculated two-dimensional transverse-electric-like photonic band diagrams and the three-dimensional dispersion surfaces near the first Γ-point band edge of unidirectionally strained PhCs. A broken rotational symmetry in the PhCs modifies the photonic band structures and results in the asymmetric distributions and different levels of changes in normalized frequencies near the first Γ-point band edge in the reciprocal space, which consequently reveals strain-dependent directional optical losses and selected emission patterns. The calculated electric fields, resonant wavelengths, and quality factors of the band-edge modes in the strained PhCs show an excellent agreement with the results of qualitative analysis of modified dispersion surfaces. Furthermore, polarization-resolved time-averaged Poynting vectors exhibit characteristic dipole-like emission patterns with preferentially selected linear polarizations, originating from the asymmetric band structures in the strained PhCs.

Experimental Study of Electronic Quantum Interference, Photonic Crystal Cavity, Photonic Band Edge Effects for Optical Amplification

DTIC Science & Technology

2016-01-26

MONITOR’S REPORT Kirtland AFB, NM 87117-5776 NUMBER(S) AFRL -RV-PS-TR-2016-0003 12. DISTRIBUTION / AVAILABILITY STATEMENT Approved for public release...22060-6218 1 cy AFRL /RVIL Kirtland AFB, NM 87117-5776 2 cys Official Record Copy AFRL /RVSS/David Cardimona 1 cy 12 Approved for... AFRL -RV-PS- AFRL -RV-PS- TR-2016-0003 TR-2016-0003 EXPERIMENTAL STUDY OF ELECTRONIC QUANTUM INTERFERENCE, PHOTONIC CRYSTAL CAVITY, PHOTONIC BAND

Widely tunable eye-safe laser by a passively Q-switched photonic crystal fiber laser and an external-cavity optical parametric oscillator

NASA Astrophysics Data System (ADS)

Chang, H. L.; Zhuang, W. Z.; Huang, W. C.; Huang, J. Y.; Huang, K. F.; Chen, Y. F.

2011-09-01

We report on a widely tunable passively Q-switched photonic crystal fiber (PCF) laser with wavelength tuning range up to 80 nm. The PCF laser utilizes an AlGaInAs quantum well/barrier structure as a saturable absorber and incorporates an external-cavity optical parametric oscillator (OPO) to achieve wavelength conversion. Under a pump power of 13.1 W at 976 nm, the PCF laser generated 1029-nm radiation with maximum output energy of 750 μJ and was incident into an external-cavity OPO. The output energy and peak power of signal wave was found to be 138 μJ and 19 kW, respectively. By tuning the temperature of nonlinear crystal, periodically poled lithium niobate (PPLN), in the OPO, the signal wavelength in eye-safe regime from 1513 to 1593 nm was obtained.

High sensitivity and high Q-factor nanoslotted parallel quadrabeam photonic crystal cavity for real-time and label-free sensing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Daquan; State Key Laboratory of Information Photonics and Optical Communications, School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876; School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138

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.

Control of Fano resonances in photonic crystal nanobeams side-coupled with nanobeam cavities and their applications to refractive index sensing

NASA Astrophysics Data System (ADS)

Meng, Zi-Ming; Li, Zhi-Yuan

2018-03-01

We study the control of Fano resonances in a 2D photonic crystal nanobeam (PCN) side-coupled with a photonic crystal nanobeam cavity (PCNC) by choosing different cavity modes, the position of the photonic bandgap of PCNs and the displacement between PCNs and PCNCs. By increasing the refractive index of the holes and the surrounding medium, it is found that the air mode cavity with even mirror-reflection symmetry holds the highest sensitivity (538 nm/RIU RIU, refractive index unit) and maximal figure of merit (FOM  =  516). Our results can be extended to a practical 3D configuration, where an air-suspended silicon PCN is side-coupled with a PCNC. Although the sensitivity is only 192 nm/RIU for our 3D structures, the maximal FOM is as large as 2095 due to the deep transmission valley. The sensitivity of our PCN-PCNC structures can be further improved by designing PCNCs with electric field concentrated in the air region as much as possible. Our PCN-PCNC structures do not require ultrahigh Q and can be fabricated on the silicon-on-insulator platform, which is compatible with CMOS processing. Therefore, our proposed PCN-PCNC structures provide feasible solutions for realizing label-free sensitive integrated refractive index sensors.

Topological Transport of Light and Sound

NASA Astrophysics Data System (ADS)

Brendel, Christian; Peano, Vittorio; Schmidt, Michael; Marquardt, Florian

Since they exploit global features of a material's band structure, topological states of matter are particularly robust. Having already been observed for electrons, atoms, and photons, it is an outstanding challenge to create a Chern insulator of sound waves in the solid state. In this work, we propose an implementation based on cavity optomechanics in a photonic crystal. We demonstrate the feasibility of our proposal by means of an effective lattice model as well as first principle simulations. The topological properties of the sound waves can be wholly tuned in situ by adjusting the amplitude and frequency of a driving laser that controls the optomechanical interaction between light and sound. The resulting chiral, topologically protected phonon transport can be probed completely optically.

Enhancing quantum effects via periodic modulations in optomechanical systems

NASA Astrophysics Data System (ADS)

Farace, Alessandro; Giovannetti, Vittorio

2012-07-01

Parametrically modulated optomechanical systems have been recently proposed as a simple and efficient setting for the quantum control of a micromechanical oscillator: relevant possibilities include the generation of squeezing in the oscillator position (or momentum) and the enhancement of entanglement between mechanical and radiation modes. In this paper we further investigate this modulation regime, considering an optomechanical system with one or more parameters being modulated over time. We first apply a sinusoidal modulation of the mechanical frequency and characterize the optimal regime in which the visibility of purely quantum effects is maximal. We then introduce a second modulation on the input laser intensity and analyze the interplay between the two. We find that an interference pattern shows up, so that different choices of the relative phase between the two modulations can either enhance or cancel the desired quantum effects, opening new possibilities for optimal quantum control strategies.

Mode suppression in metal filled photonic crystal vertical cavity lasers

NASA Astrophysics Data System (ADS)

Griffin, Benjamin G.; Arbabi, Amir; Goddard, Lynford L.

2012-03-01

Simulation results for an etched air hole photonic crystal (PhC) vertical cavity surface emitting laser (VCSEL) structure with various thicknesses of metal deposited inside the holes are presented. The higher-order modes of the structure are more spread out than the fundamental mode, and penetrate into the metal-filled holes. Due to the lossy nature of the metal, these higher-order modes experience a greater loss than the fundamental mode, resulting in an enhanced side mode suppression ratio (SMSR). A figure of merit for determining which metals would have the greatest impact on the SMSR is derived and validated using a transmission matrix method calculation. A full three-dimensional simulation of the PhC VCSEL structure is performed using the plane wave admittance method, and SMSRs are calculated for increasing metal thicknesses. Of the metals simulated, chromium provided the greatest SMSR enhancement with more than a 4 dB improvement with 500 nm of metal for an operating current of 12 times threshold.

Determination of thermally induced effects and design guidelines of optomechanical accelerometers

NASA Astrophysics Data System (ADS)

Lu, Qianbo; Bai, Jian; Wang, Kaiwei; Jiao, Xufen; Han, Dandan; Chen, Peiwen; Liu, Dong; Yang, Yongying; Yang, Guoguang

2017-11-01

Thermal effects, including thermally induced deformation and warm up time, are ubiquitous problems for sensors, especially for inertial measurement units such as accelerometers. Optomechanical accelerometers, which contain light sources that can be regarded as heat sources, involve a different thermal phenomenon in terms of their specific optical readout, and the phenomenon has not been investigated systematically. This paper proposes a model to evaluate the temperature difference, rise time and thermally induced deformation of optomechanical accelerometers, and then constructs design guidelines which can diminish these thermal effects without compromising other mechanical performances, based on the analysis of the interplay of thermal and mechanical performances. In the model, the irradiation of the micromachined structure of a laser source is considered a dominant factor. The experimental data obtained using a prototype of an optomechanical accelerometer approximately confirm the validity of the model for the rise time and response tendency. Moreover, design guidelines that adopt suspensions with a flat cross-section and a short length are demonstrated with reference to the analysis. The guidelines can reduce the thermally induced deformation and rise time or achieve higher mechanical performances with similar thermal effects, which paves the way for the design of temperature-tolerant and robust, high-performance devices.

Demonstration of enhanced side-mode suppression in metal-filled photonic crystal vertical cavity lasers.

PubMed

Griffin, Benjamin G; Arbabi, Amir; Peun Tan, Meng; Kasten, Ansas M; Choquette, Kent D; Goddard, Lynford L

2013-06-01

Previously reported simulations have suggested that depositing thin layers of metal over the surface of a single-mode, etched air hole photonic crystal (PhC) vertical-cavity surface-emitting laser (VCSEL) could potentially improve the laser's side-mode suppression ratio by introducing additional losses to the higher-order modes. This work demonstrates the concept by presenting the results of a 30 nm thin film of Cr deposited on the surface of an implant-confined PhC VCSEL. Both experimental measurements and simulation results are in agreement showing that the single-mode operation is improved at the same injection current ratio relative to threshold.

Quantum Optomechanics with Silicon Nanostructures

NASA Astrophysics Data System (ADS)

Safavi-Naeini, Amir H.

Mechanical resonators are the most basic and ubiquitous physical systems known. In on-chip form, they are used to process high frequency signals in every cell phone, television, and laptop. They have also been in the last few decades in different shapes and forms, a critical part of progress in quantum information sciences with kilogram scale mirrors for gravitational wave detection measuring motion at its quantum limits, and the motion of single ions being used to link qubits for quantum computation. Optomechanics is a field primarily concerned with coupling light to the motion of mechanical structures. This thesis contains descriptions of recent work with mechanical systems in the megahertz to gigahertz frequency range, formed by nanofabricating novel photonic/phononic structures on a silicon chip. These structures are designed to have both optical and mechanical resonances, and laser light is used to address and manipulate their motional degrees of freedom through radiation pressure forces. We laser cool these mechanical resonators to their ground states, and observe for the first time the quantum zero-point motion of a nanomechanical resonator. Conversely, we show that engineered mechanical resonances drastically modify the optical response of our structures, creating large effective optical nonlinearities not present in bulk silicon. We experimentally demonstrate aspects of these nonlinearities by proposing and observing ``electromagnetically induced transparency'' and light slowed down to 6 m/s, as well as wavelength conversion, and generation of nonclassical optical radiation. Finally, the application of optomechanics to longstanding problems in quantum and classical communications are proposed and investigated.

Opto-mechanical door locking system

NASA Astrophysics Data System (ADS)

Patil, Saurabh S.; Rodrigues, Vanessa M.; Patil, Ajeetkumar; Chidangil, Santhosh

2015-09-01

We present an Opto-mechanical Door Locking System which is an optical system that combines a simple combination of a coherent light source (Laser) and a photodiode based sensor with focus toward security applications. The basic construct of the KEY comprises a Laser source in a cylindrical enclosure that slides perfectly into the LOCK. The Laser is pulsed at a fixed encrypted frequency unique to that locking system. Transistor-transistor logic (TTL) circuitry is used to achieve encryption. The casing of the key is designed in such a way that it will power the pulsing laser only when the key is inserted in the slot provided for it. The Lock includes a photo-sensor that will convert the detected light intensity to a corresponding electrical signal by decrypting the frequency. The lock also consists of a circuit with a feedback system that will carry the digital information regarding the encryption frequency code. The information received from the sensor is matched with the stored code; if found a perfect match, a signal will be sent to the servo to unlock the mechanical lock or to carry out any other operation. This technique can be incorporated in security systems for residences and safe houses, and can easily replace all conventional locks which formerly used fixed patterns to unlock. The major advantage of this proposed optomechanical system over conventional ones is that it no longer relies on a solid/imprinted pattern to perform its task and hence makes it almost impossible to tamper with.

Study of thermally-induced optical bistability and the role of surface treatments in Si-based mid-infrared photonic crystal cavities.

PubMed

Shankar, Raji; Bulu, Irfan; Leijssen, Rick; Lončar, Marko

2011-11-21

We report the observation of optical bistability in Si-based photonic crystal cavities operating around 4.5 µm. Time domain measurements indicate that the source of this optical bistability is thermal, with a time constant on the order of 5 µs. Quality (Q) factor improvement is shown by the use of surface treatments (wet processes and annealing), resulting in a significant increase in Q-factor, which in our best devices is on the order of ~45,000 at 4.48 µm. After annealing in a N(2) environment, optical bistability is no longer seen in our cavities. © 2011 Optical Society of America

Investigation of the influence of the proximity effect and randomness on a photolithographically fabricated photonic crystal nanobeam cavity

NASA Astrophysics Data System (ADS)

Tetsumoto, Tomohiro; Kumazaki, Hajime; Ishida, Rammaru; Tanabe, Takasumi

2018-01-01

Recent progress on the fabrication techniques used in silicon photonics foundries has enabled us to fabricate photonic crystal (PhC) nanocavities using a complementary metal-oxide-semiconductor (CMOS) compatible process. A high Q two-dimensional PhC nanocavity and a one-dimensional nanobeam PhC cavity with a Q exceeding 100 thousand have been fabricated using ArF excimer laser immersion lithography. These are important steps toward the fusion of silicon photonics devices and PhC devices. Although the fabrication must be reproducible for industrial applications, the properties of PhC nanocavities are sensitively affected by the proximity effect and randomness. In this study, we quantitatively investigated the influence of the proximity effect and randomness on a silicon nanobeam PhC cavity. First, we discussed the optical properties of cavities defined with one- and two-step exposure methods, which revealed the necessity of a multi-stage exposure process for our structure. Then, we investigated the impact of block structures placed next to the cavities. The presence of the blocks modified the resonant wavelength of the cavities by about 10 nm. The highest Q we obtained was over 100 thousand. We also discussed the influence of photomask misalignment, which is also a possible cause of disorders in the photolithographic fabrication process. This study will provide useful information for fabricating integrated photonic circuits with PhC nanocavities using a photolithographic process.

Metallic dielectric photonic crystals and methods of fabrication

DOEpatents

Chou, Jeffrey Brian; Kim, Sang-Gook

2017-12-05

A metallic-dielectric photonic crystal is formed with a periodic structure defining a plurality of resonant cavities to selectively absorb incident radiation. A metal layer is deposited on the inner surfaces of the resonant cavities and a dielectric material fills inside the resonant cavities. This photonic crystal can be used to selectively absorb broadband solar radiation and then reemit absorbed radiation in a wavelength band that matches the absorption band of a photovoltaic cell. The photonic crystal can be fabricated by patterning a sacrificial layer with a plurality of holes, into which is deposited a supporting material. Removing the rest of the sacrificial layer creates a supporting structure, on which a layer of metal is deposited to define resonant cavities. A dielectric material then fills the cavities to form the photonic crystal.

Metallic dielectric photonic crystals and methods of fabrication

DOEpatents

Chou, Jeffrey Brian; Kim, Sang-Gook

2016-12-20

A metallic-dielectric photonic crystal is formed with a periodic structure defining a plurality of resonant cavities to selectively absorb incident radiation. A metal layer is deposited on the inner surfaces of the resonant cavities and a dielectric material fills inside the resonant cavities. This photonic crystal can be used to selectively absorb broadband solar radiation and then reemit absorbed radiation in a wavelength band that matches the absorption band of a photovoltaic cell. The photonic crystal can be fabricated by patterning a sacrificial layer with a plurality of holes, into which is deposited a supporting material. Removing the rest of the sacrificial layer creates a supporting structure, on which a layer of metal is deposited to define resonant cavities. A dielectric material then fills the cavities to form the photonic crystal.

On-chip integrated optofluidic complex refractive index sensing using silicon photonic crystal nanobeam cavities.

PubMed

Zhang, Xingwang; Zhou, Guangya; Shi, Peng; Du, Han; Lin, Tong; Teng, Jinghua; Chau, Fook Siong

2016-03-15

Complex refractive index sensing is proposed and experimentally demonstrated in optofluidic sensors based on silicon photonic crystal nanobeam cavities. The sensitivities are 58 and 139 nm/RIU, respectively, for the real part (n) and the imaginary part (κ) of the complex refractive index, and the corresponding detection limits are 1.8×10(-5) RIU for n and 4.1×10(-6) RIU for κ. Moreover, the capability of the complex refractive index sensing method to detect the concentration composition of the ternary mixture is demonstrated without the surface immobilization of functional groups, which is impossible to realize with the conventional refractive index sensing scheme.

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation.

PubMed

Nayak, Kali Prasanna; Keloth, Jameesh; Hakuta, Kohzo

2017-02-25

We present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using femtosecond laser-induced ablation. We show that thousands of periodic nano-craters are fabricated on an optical nanofiber by irradiating with just a single femtosecond laser pulse. For a typical sample, periodic nano-craters with a period of 350 nm and with diameter gradually varying from 50 - 250 nm over a length of 1 mm are fabricated on a nanofiber with diameter around 450 - 550 nm. A key aspect of such a nanofabrication is that the nanofiber itself acts as a cylindrical lens and focuses the femtosecond laser beam on its shadow surface. Moreover, the single-shot fabrication makes it immune to mechanical instabilities and other fabrication imperfections. Such periodic nano-craters on nanofiber, act as a 1-D PhC and enable strong and broadband reflection while maintaining the high transmission out of the stopband. We also present a method to control the profile of the nano-crater array to fabricate apodized and defect-induced PhC cavities on the nanofiber. The strong confinement of the field, both transverse and longitudinal, in the nanofiber-based PhC cavities and the efficient integration to the fiber networks, may open new possibilities for nanophotonic applications and quantum information science.

Switching of Photonic Crystal Lasers by Graphene.

PubMed

Hwang, Min-Soo; Kim, Ha-Reem; Kim, Kyoung-Ho; Jeong, Kwang-Yong; Park, Jin-Sung; Choi, Jae-Hyuck; Kang, Ju-Hyung; Lee, Jung Min; Park, Won Il; Song, Jung-Hwan; Seo, Min-Kyo; Park, Hong-Gyu

2017-03-08

Unique features of graphene have motivated the development of graphene-integrated photonic devices. In particular, the electrical tunability of graphene loss enables high-speed modulation of light and tuning of cavity resonances in graphene-integrated waveguides and cavities. However, efficient control of light emission such as lasing, using graphene, remains a challenge. In this work, we demonstrate on/off switching of single- and double-cavity photonic crystal lasers by electrical gating of a monolayer graphene sheet on top of photonic crystal cavities. The optical loss of graphene was controlled by varying the gate voltage V g , with the ion gel atop the graphene sheet. First, the fundamental properties of graphene were investigated through the transmittance measurement and numerical simulations. Next, optically pumped lasing was demonstrated for a graphene-integrated single photonic crystal cavity at V g below -0.6 V, exhibiting a low lasing threshold of ∼480 μW, whereas lasing was not observed at V g above -0.6 V owing to the intrinsic optical loss of graphene. Changing quality factor of the graphene-integrated photonic crystal cavity enables or disables the lasing operation. Moreover, in the double-cavity photonic crystal lasers with graphene, switching of individual cavities with separate graphene sheets was achieved, and these two lasing actions were controlled independently despite the close distance of ∼2.2 μm between adjacent cavities. We believe that our simple and practical approach for switching in graphene-integrated active photonic devices will pave the way toward designing high-contrast and ultracompact photonic integrated circuits.

Macroscopic Entangled State Generation with Optomechanical Coupling of Two Mechanical Modes

NASA Astrophysics Data System (ADS)

Weaver, Matthew; Luna, Fernando; Buters, Frank; Heeck, Kier; de Man, Sven; Bouwmeester, Dirk

Mechanical resonators with a large quantum position uncertainty are an excellent test system for proposed decoherence mechanisms in massive systems. We present a scheme to optomechanically entangle two mechanical resonators with large frequency separation via two tone driving and single photon projection measurements. The quantum position uncertainty can be tuned with a variable optical pulse displacement operation, and independent single photon readout of the two resonators provides robust verification of the quantum states of the system. This scheme is currently experimentally feasible in a number of high mass opto- and electro-mechanical systems. We demonstrate one such system with two spatially and frequency separated Si3N4 trampoline resonators. We also show how the resonators can be coupled with two tone driving and the single photon optomechanical coupling rates can be tuned.

Photon blockade in optomechanical systems with a position-modulated Kerr-type nonlinear coupling

NASA Astrophysics Data System (ADS)

Zhang, X. Y.; Zhou, Y. H.; Guo, Y. Q.; Yi, X. X.

2018-03-01

We explore the photon blockade in optomechanical systems with a position-modulated Kerr-type nonlinear coupling, i.e. H_int˜\\hat{a}\\dagger2\\hat{a}^2(\\hat{b}_1^\\dagger+\\hat{b}_1) . We find that the Kerr-type nonlinear coupling can enhance the photon blockade greatly. We evaluate the equal-time second-order correlation function of the cavity photons and find that the optimal photon blockade does not happen at the single photon resonance. By working within the few-photon subspace, we get an approximate analytical expression for the correlation function and the condition for the optimal photon blockade. We also find that the photon blockade effect is not always enhanced as the Kerr-type nonlinear coupling strength g 2 increases. At some values of g 2, the photon blockade is even weakened. For the system we considered here, the second-order correlation function can be smaller than 1 even in the unresolved sideband regime. By numerically simulating the master equation of the system, we also find that the thermal noise of the mechanical environment can enhance the photon blockade. We give out an explanation for this counter-intuitive phenomenon qualitatively.

Multi-harmonic quantum dot optomechanics in fused LiNbO3-(Al)GaAs hybrids

NASA Astrophysics Data System (ADS)

Nysten, Emeline D. S.; Huo, Yong Heng; Yu, Hailong; Song, Guo Feng; Rastelli, Armando; Krenner, Hubert J.

2017-11-01

We fabricated an acousto-optic semiconductor hybrid device for strong optomechanical coupling of individual quantum emitters and a surface acoustic wave. Our device comprises of a surface acoustic wave chip made from highly piezoelectric LiNbO3 and a GaAs-based semiconductor membrane with an embedded layer of quantum dots. Employing multi-harmonic transducers, we generated sound waves on LiNbO3 over a wide range of radio frequencies. We monitored their coupling to and propagation across the semiconductor membrane, both in the electrical and optical domain. We demonstrate the enhanced optomechanical tuning of the embedded quantum dots with increasing frequencies. This effect was verified by finite element modelling of our device geometry and attributed to an increased localization of the acoustic field within the semiconductor membrane. For moderately high acoustic frequencies, our simulations predict strong optomechanical coupling, making our hybrid device ideally suited for applications in semiconductor based quantum acoustics.

Electromagnetic diode based on photonic crystal cavity with embedded highly dispersive meta-interface

NASA Astrophysics Data System (ADS)

Chen, Yongqiang; Dong, Lijuan; Xu, Xiaohu; Jiang, Jun; Shi, Yunlong

2017-12-01

In this paper, we propose a scheme for subwavelength electromagnetic diodes by employing a photonic crystal (PC) cavity with embedded electromagnetically induced-transparency (EIT)-like highly dispersive meta-interface. A nonreciprocal response, with 21.5 dB transmission light contrast and 12.3 dBm working power, is conceptually demonstrated in a microstrip transmission line system with asymmetric absorption and nonlinear medium inclusion. Such high-contrast transmission and relatively low-threshold diode action stem from the composite PC-EIT mechanism. This mechanism not only possesses a large quality factor and strong localization of fields but also does not enlarge the device volume and drastically reduce transmittance. Our findings should be beneficial for the design of new and practical metamaterial-enabled nonlinear devices.

Carrier-envelope phase-dependent effect of high-order sideband generation in ultrafast driven optomechanical system.

PubMed

Xiong, Hao; Si, Liu-Gang; Lü, Xin-You; Yang, Xiaoxue; Wu, Ying

2013-02-01

We analyze the features of the output field of a generic optomechanical system that is driven by a control field and a nanosecond driven pulse, and find a robust high-order sideband generation in optomechanical systems. The typical spectral structure, plateau and cutoff, confirms the nonperturbative nature of the effect, which is similar to high-order harmonic generation in atoms or molecules. Based on the phenomenon, we show that the carrier-envelope phase of laser pulses that contain huge numbers of cycles can cause profound effects.

The Wide Integral Field Infrared Spectrograph (WIFIS): optomechanical design and development

NASA Astrophysics Data System (ADS)

Meyer, R. Elliot; Moon, Dae-Sik; Sivanandam, Suresh; Ma, Ke; Henderson, Chuck; Blank, Basil; Chou, Chueh-Yi; Jarvis, Miranda; Eikenberry, Stephen S.

2016-08-01

We present the optomechanical design and development of the Wide Integral Field Infrared Spectrograph (WIFIS). WIFIS will provide an unrivalled integral field size of 20"×50" for a near-infrared (0.9-1.7 μm) integral-field spectrograph at the 2.3-meter Steward Bok telescope. Its main optomechanical system consists of two assemblies: a room-temperature bench housing the majority of the optical components and a cryostat for a field-flattening lens, thermal blocking filter, and detector. Two additional optical subsystems will provide calibration functionality, telescope guiding, and off-axis optical imaging. WIFIS will be a highly competitive instrument for seeing-limited astronomical investigations of the dynamics and chemistry of extended objects in the near-infrared wavebands. WIFIS is expected to be commissioned during the end of 2016 with scientific operations beginning in 2017.

Imaging and tuning of coupled photonic crystal cavities (Conference Presentation)

NASA Astrophysics Data System (ADS)

Gurioli, Massimo

2016-04-01

Photonic microcavities (PMC) coupled through their evanescent field are used for a large variety of classical and quantum devices. In such systems, a molecular-like spatial delocalization of the coupled modes is achieved by an evanescent tunnelling. The tunnelling rate depends on the height and depth of the photonic barrier between two adjacent resonators and therefore it is sensitive to the fabrication-induced disorder present in the center of the molecule. In this contribution, we address the problem of developing a post fabrication control of the tunnelling rate in photonic crystal coupled PMCs. The value of the photonic coupling (proportional to the tunnelling rate) is directly measured by the molecular mode splitting at the anticrossing point. By exploiting a combination of tuning techniques such as local infiltration of water, micro-evaporation, and laser induced non thermal micro-oxidation, we are able to either increase or decrease the detuning and the photonic coupling, independently. Near field imaging is also used for mapping the modes and establish delocalization. By water micro-infiltration, we were able to increase the photon coupling by 28%. On the contrary, by laser induced non thermal oxidation, we got a reduction of g by 30%. The combination of the two methods would therefore give a complete control of g with excellent accuracy. This could make possible the realization of array of photonic cavities with on demand tunnelling rate between each pair of coupled resonators. We believe that this peculiar engineering of photonic crystal molecules would open the road to possible progress in the exploitation of coherent interference between coupled optical resonators both for quantum information processing and optical communication.

Semi-monolithic cavity for external resonant frequency doubling and method of performing the same

NASA Technical Reports Server (NTRS)

Hemmati, Hamid (Inventor)

1999-01-01

The fabrication of an optical cavity for use in a laser, in a frequency doubling external cavity, or any other type of nonlinear optical device, can be simplified by providing the nonlinear crystal in combination with a surrounding glass having an index of refraction substantially equal to that of the nonlinear crystal. The closed optical path in this cavity is formed in the surrounding glass and through the nonlinear crystal which lies in one of the optical segments of the light path. The light is transmitted through interfaces between the surrounding glass in the nonlinear crystal through interfaces which are formed at the Brewster-angle to minimize or eliminate reflection.

Tuning the Cavity Size and Chirality of Self-Assembling 3D DNA Crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simmons, Chad R.; Zhang, Fei; MacCulloch, Tara

The foundational goal of structural DNA nanotechnology—the field that uses oligonucleotides as a molecular building block for the programmable self-assembly of nanostructured systems—was to use DNA to construct three-dimensional (3D) lattices for solving macromolecular structures. The programmable nature of DNA makes it an ideal system for rationally constructing self-assembled crystals and immobilizing guest molecules in a repeating 3D array through their specific stereospatial interactions with the scaffold. In this work, we have extended a previously described motif (4 × 5) by expanding the structure to a system that links four double-helical layers; we use a central weaving oligonucleotide containing amore » sequence of four six-base repeats (4 × 6), forming a matrix of layers that are organized and dictated by a series of Holliday junctions. In addition, we have assembled mirror image crystals (l-DNA) with the identical sequence that are completely resistant to nucleases. Bromine and selenium derivatives were obtained for the l- and d-DNA forms, respectively, allowing phase determination for both forms and solution of the resulting structures to 3.0 and 3.05 Å resolution. Both right- and left-handed forms crystallized in the trigonal space groups with mirror image 3-fold helical screw axes P32 and P31 for each motif, respectively. The structures reveal a highly organized array of discrete and well-defined cavities that are suitable for hosting guest molecules and allow us to dictate a priori the assembly of guest–DNA conjugates with a specified crystalline hand.« less

Stimulated Optomechanical Excitation of Surface Acoustic Waves in a Microdevice

DTIC Science & Technology

2011-07-26

Cohadon, P.- F., Briant, T., Pinard, M. & Heidmann, A. Radiation- pressure cooling and optomechanical instability of a micromirror . Nature 444, 71–74...2006). 6. Gigan, S. et al. Self-cooling of a micromirror by radiation pressure. Nature 444, 67–70 (2006). 7. Kleckner, D. & Bouwmeester, D. Sub-kelvin

Ultra-compact air-mode photonic crystal nanobeam cavity integrated with bandstop filter for refractive index sensing.

PubMed

Sun, Fujun; Fu, Zhongyuan; Wang, Chunhong; Ding, Zhaoxiang; Wang, Chao; Tian, Huiping

2017-05-20

We propose and investigate an ultra-compact air-mode photonic crystal nanobeam cavity (PCNC) with an ultra-high quality factor-to-mode volume ratio (Q/V) by quadratically tapering the lattice space of the rectangular holes from the center to both ends while other parameters remain unchanged. By using the three-dimensional finite-difference time-domain method, an optimized geometry yields a Q of 7.2×10 6 and a V∼1.095(λ/n Si ) 3 in simulations, resulting in an ultra-high Q/V ratio of about 6.5×10 6 (λ/n Si ) -3 . When the number of holes on either side is 8, the cavity possesses a high sensitivity of 252 nm/RIU (refractive index unit), a high calculated Q-factor of 1.27×10 5 , and an ultra-small effective V of ∼0.758(λ/n Si ) 3 at the fundamental resonant wavelength of 1521.74 nm. Particularly, the footprint is only about 8×0.7  μm 2 . However, inevitably our proposed PCNC has several higher-order resonant modes in the transmission spectrum, which makes the PCNC difficult to be used for multiplexed sensing. Thus, a well-designed bandstop filter with weak sidelobes and broad bandwidth based on a photonic crystal nanobeam waveguide is created to connect with the PCNC to filter out the high-order modes. Therefore, the integrated structure presented in this work is promising for building ultra-compact lab-on-chip sensor arrays with high density and parallel-multiplexing capability.

Quantum optomechanical piston engines powered by heat

NASA Astrophysics Data System (ADS)

Mari, A.; Farace, A.; Giovannetti, V.

2015-09-01

We study two different models of optomechanical systems where a temperature gradient between two radiation baths is exploited for inducing self-sustained coherent oscillations of a mechanical resonator. From a thermodynamic perspective, such systems represent quantum instances of self-contained thermal machines converting heat into a periodic mechanical motion and thus they can be interpreted as nano-scale analogues of macroscopic piston engines. Our models are potentially suitable for testing fundamental aspects of quantum thermodynamics in the laboratory and for applications in energy efficient nanotechnology.

Q factor limitation at short wavelength (around 300 nm) in III-nitride-on-silicon photonic crystal cavities

NASA Astrophysics Data System (ADS)

Tabataba-Vakili, Farsane; Roland, Iannis; Tran, Thi-Mo; Checoury, Xavier; El Kurdi, Moustafa; Sauvage, Sébastien; Brimont, Christelle; Guillet, Thierry; Rennesson, Stéphanie; Duboz, Jean-Yves; Semond, Fabrice; Gayral, Bruno; Boucaud, Philippe

2017-09-01

III-nitride-on-silicon L3 photonic crystal cavities with resonances down to 315 nm and quality factors (Q) up to 1085 at 337 nm have been demonstrated. The reduction of the quality factor with decreasing wavelength is investigated. Besides the quantum well absorption below 340 nm, a noteworthy contribution is attributed to the residual absorption present in thin AlN layers grown on silicon, as measured by spectroscopic ellipsometry. This residual absorption ultimately limits the Q factor to around 2000 at 300 nm when no active layer is present.

Cavity enhanced interference of orthogonal modes in a birefringent medium

NASA Astrophysics Data System (ADS)

Kolluru, Kiran; Saha, Sudipta; Gupta, S. Dutta

2018-03-01

Interference of orthogonal modes in a birefringent crystal mediated by a rotator is known to lead to interesting physical effects (Solli et al., 2003). In this paper we show that additional feedback offered by a Fabry-Perot cavity (containing the birefringent crystal and the rotator) can lead to a novel strong interaction regime. Usual signatures of the strong interaction regime like the normal mode splitting and avoided crossings, sensitive to the rotator orientation, are reported. A high finesse cavity is shown to offer an optical setup for measuring small angles. The results are based on direct calculations of the cavity transmissions along with an analysis of its dispersion relation.

Temperature-insensitive refractive index sensing by use of micro Fabry-Pérot cavity based on simplified hollow-core photonic crystal fiber.

PubMed

Wang, Ying; Wang, D N; Liao, C R; Hu, Tianyi; Guo, Jiangtao; Wei, Huifeng

2013-02-01

A temperature-insensitive micro Fabry-Pérot (FP) cavity based on simplified hollow-core (SHC) photonic crystal fiber (PCF) is demonstrated. Such a device is fabricated by splicing a section of SHC PCF with single mode fibers at both cleaved ends. An extremely low temperature sensitivity of ~0.273 pm/°C is obtained between room temperature and 900°C. By drilling vertical micro-channels using a femtosecond laser, the micro FP cavity can be filled with liquids and functions as a sensitive refractometer and the refractive index sensitivity obtained is ~851.3 nm/RIU (refractive index unit), which indicates an ultra low temperature cross-sensitivity of ~3.2×10(-7) RIU/°C.

Cavity-enhanced frequency doubling from 795nm to 397.5nm ultra-violet coherent radiation with PPKTP crystals in the low pump power regime.

PubMed

Wen, Xin; Han, Yashuai; Bai, Jiandong; He, Jun; Wang, Yanhua; Yang, Baodong; Wang, Junmin

2014-12-29

We demonstrate a simple, compact and cost-efficient diode laser pumped frequency doubling system at 795 nm in the low power regime. In two configurations, a bow-tie four-mirror ring enhancement cavity with a PPKTP crystal inside and a semi-monolithic PPKTP enhancement cavity, we obtain 397.5nm ultra-violet coherent radiation of 35mW and 47mW respectively with a mode-matched fundamental power of about 110mW, corresponding to a conversion efficiency of 32% and 41%. The low loss semi-monolithic cavity leads to the better results. The constructed ultra-violet coherent radiation has good power stability and beam quality, and the system has huge potential in quantum optics and cold atom physics.

Nanofriction in Cavity Quantum Electrodynamics

NASA Astrophysics Data System (ADS)

Fogarty, T.; Cormick, C.; Landa, H.; Stojanović, Vladimir M.; Demler, E.; Morigi, Giovanna

2015-12-01

The dynamics of cold trapped ions in a high-finesse resonator results from the interplay between the long-range Coulomb repulsion and the cavity-induced interactions. The latter are due to multiple scatterings of laser photons inside the cavity and become relevant when the laser pump is sufficiently strong to overcome photon decay. We study the stationary states of ions coupled with a mode of a standing-wave cavity as a function of the cavity and laser parameters, when the typical length scales of the two self-organizing processes, Coulomb crystallization and photon-mediated interactions, are incommensurate. The dynamics are frustrated and in specific limiting cases can be cast in terms of the Frenkel-Kontorova model, which reproduces features of friction in one dimension. We numerically recover the sliding and pinned phases. For strong cavity nonlinearities, they are in general separated by bistable regions where superlubric and stick-slip dynamics coexist. The cavity, moreover, acts as a thermal reservoir and can cool the chain vibrations to temperatures controlled by the cavity parameters and by the ions' phase. These features are imprinted in the radiation emitted by the cavity, which is readily measurable in state-of-the-art setups of cavity quantum electrodynamics.

Cavity Enhanced Absorption Spectroscopy Using a Broadband Prism Cavity and a Supercontinuum Source

NASA Astrophysics Data System (ADS)

Johnston, Paul S.; Lehmann, Kevin K.

2009-06-01

The multiplex advantage of current cavity enhanced spectrometers is limited by the high reflectivity bandwidth of the mirrors used to construct the high finesse cavity. Previously, we reported the design and construction of a new spectrometer that circumvents this limitation by utilizing Brewster^{,}s angle prism retroreflectors. The prisms, made from fused silica and combined with a supercontinuum source generated by pumping a highly nonlinear photonic crystal fiber, yields a spectral window ranging from 500 nm to 1750 nm. Recent progress in the instruments development will be discussed, including work on modeling the prism cavity losses, alternative prism material for use in the UV and mid-IR spectral regions, and a new high power supercontinuum source based on mode-locked picosecond laser.

Observations of cavity polaritons in one-dimensional photonic crystals containing a liquid-crystalline semiconductor based on perylene bisimide units

NASA Astrophysics Data System (ADS)

Sakata, T.; Suzuki, M.; Yamamoto, T.; Nakanishi, S.; Funahashi, M.; Tsurumachi, N.

2017-10-01

We investigated the optical transmission properties of one-dimensional photonic crystal (1D-PC) microcavity structures containing the liquid-crystalline (LC) perylene tetracarboxylic bisimide (PTCBI) derivative. We fabricated the microcavity structures for this study by two different methods and observed the cavity polaritons successfully in both samples. For one sample, since the PTCBI molecules were aligned in the cavity layer of the 1D-PC by utilizing a friction transfer method, vacuum Rabi splitting energy was strongly dependent on the polarization of the incident light produced by the peculiar optical features of the LC organic semiconductor. For the other sample, we did not utilize the friction transfer method and did not observe such polarization dependence. However, we did observe a relatively large Rabi splitting energy of 187 meV, probably due to the improvement of optical confinement effect.

In-phased second harmonic wave array generation with intra-Talbot-cavity frequency-doubling.

PubMed

Hirosawa, Kenichi; Shohda, Fumio; Yanagisawa, Takayuki; Kannari, Fumihiko

2015-03-23

The Talbot cavity is one promising method to synchronize the phase of a laser array. However, it does not achieve the lowest array mode with the same phase but the highest array mode with the anti-phase between every two adjacent lasers, which is called out-phase locking. Consequently, their far-field images exhibit 2-peak profiles. We propose intra-Talbot-cavity frequency-doubling. By placing a nonlinear crystal in a Talbot cavity, the Talbot cavity generates an out-phased fundamental wave array, which is converted into an in-phase-locked second harmonic wave array at the nonlinear crystal. We demonstrate numerical calculations and experiments on intra-Talbot-cavity frequency-doubling and obtain an in-phase-locked second harmonic wave array for a Nd:YVO₄ array laser.

Breakdown of Bose-Einstein distribution in photonic crystals.

PubMed

Lo, Ping-Yuan; Xiong, Heng-Na; Zhang, Wei-Min

2015-03-30

In the last two decades, considerable advances have been made in the investigation of nano-photonics in photonic crystals. Previous theoretical investigations of photon dynamics were carried out at zero temperature. Here, we investigate micro/nano cavity photonics in photonic crystals at finite temperature. Due to photonic-band-gap-induced localized long-lived photon dynamics, we discover that cavity photons in photonic crystals do not obey Bose-Einstein statistical distribution. Within the photonic band gap and in the vicinity of the band edge, cavity photons combine the long-lived non-Markovain dynamics with thermal fluctuations together to form photon states that memorize the initial cavity state information. As a result, Bose-Einstein distribution is completely broken down in these regimes, even if the thermal energy is larger or much larger than the cavity detuning energy. In this investigation, a crossover phenomenon from equilibrium to nonequilibrium steady states is also revealed.

A hybrid system of a membrane oscillator coupled to ultracold atoms

NASA Astrophysics Data System (ADS)

Kampschulte, Tobias

2015-05-01

The control over micro- and nanomechanical oscillators has recently made impressive progress. First experiments demonstrated ground-state cooling and single-phonon control of high-frequency oscillators using cryogenic cooling and techniques of cavity optomechanics. Coupling engineered mechanical structures to microscopic quantum system with good coherence properties offers new possibilities for quantum control of mechanical vibrations, precision sensing and quantum-level signal transduction. Ultracold atoms are an attractive choice for such hybrid systems: Mechanical can either be coupled to the motional state of trapped atoms, which can routinely be ground-state cooled, or to the internal states, for which a toolbox of coherent manipulation and detection exists. Furthermore, atomic collective states with non-classical properties can be exploited to infer the mechanical motion with reduced quantum noise. Here we use trapped ultracold atoms to sympathetically cool the fundamental vibrational mode of a Si3N4 membrane. The coupling of membrane and atomic motion is mediated by laser light over a macroscopic distance and enhanced by an optical cavity around the membrane. The observed cooling of the membrane from room temperature to 650 +/- 230 mK shows that our hybrid mechanical-atomic system operates at a large cooperativity. Our scheme could provide ground-state cooling and quantum control of low-frequency oscillators such as levitated nanoparticles, in a regime where purely optomechanical techniques cannot reach the ground state. Furthermore, we will present a scheme where an optomechanical system is coupled to internal states of ultracold atoms. The mechanical motion is translated into a polarization rotation which drives Raman transitions between atomic ground states. Compared to the motional-state coupling, the new scheme enables to couple atoms to high-frequency structures such as optomechanical crystals.

Opto-mechanical design of PANIC

NASA Astrophysics Data System (ADS)

Fried, Josef W.; Baumeister, Harald; Huber, Armin; Laun, Werner; Rohloff, Ralf-Rainer; Concepción Cárdenas, M.

2010-07-01

PANIC, the Panoramic Near-Infrared Camera, is a new instrument for the Calar Alto Observatory. A 4x4 k detector yields a field of view of 0.5x0.5 degrees at a pixel scale of 0.45 arc sec/pixel at the 2.2m telescope. PANIC can be used also at the 3.5m telescope with half the pixel scale. The optics consists of 9 lenses and 3 folding mirrors. Mechanical tolerances are as small as 50 microns for some elements. PANIC will have a low thermal background due to cold stops. Read-out is done with MPIA's own new electronics which allows read-out of 132 channels in parallel. Weight and size limits lead to interesting design features. Here we describe the opto-mechanical design.

Lateral cavity photonic crystal surface emitting lasers with ultralow threshold and large power

NASA Astrophysics Data System (ADS)

Wang, Yufei; Qu, Hongwei; Zhou, Wenjun; Jiang, Bin; Zhang, Jianxin; Qi, Aiyi; Liu, Lei; Fu, Feiya; Zheng, Wanhua

2012-03-01

The Bragg diffraction condition of surface-emitting lasing action is analyzed and Γ2-1 mode is chosen for lasing. Two types of lateral cavity photonic crystal surface emitting lasers (LC-PCSELs) based on the PhC band edge mode lateral resonance and vertical emission to achieve electrically driven surface emitting laser without distributed Bragg reflectors in the long wavelength optical communication band are designed and fabricated. Deep etching techniques, which rely on the active layer being or not etched through, are adopted to realize the LC-PCSELs on the commercial AlGaInAs/InP multi-quantum-well (MQW) epitaxial wafer. 1553.8 nm with ultralow threshold of 667 A/cm2 and 1575 nm with large power of 1.8 mW surface emitting lasing actions are observed at room temperature, providing potential values for mass production with low cost of electrically driven PCSELs.

Optomechanical design of a buckling cavity in a low-cost high-performance ferruleless field-installable single-mode fiber connector

NASA Astrophysics Data System (ADS)

Ebraert, Evert; Van Erps, Jürgen; Beri, Stefano; Watté, Jan; Thienpont, Hugo

2014-10-01

To boost the deployment of fiber-to-the-home networks in order to meet the ever-increasing demand for bandwidth, there is a strong need for single-mode fiber (SMF) connectors which combine low insertion loss with field installability. Shifting from ferrule-based to ferruleless connectors can reduce average insertion losses appreciably and minimize modal noise interference. We propose a ferruleless connector and adaptor in which physical contact between two inline fibers is ensured by at least one fiber being in a buckled state. To this end, we design a buckling cavity in which the SMF can buckle in a controlled way to ensure good optical performance as well as mechanical stability. This design is based on both mechanical and optical considerations. Finite element analysis suggests that mechanically a minimal buckling cavity length of 17 mm is required, while the height of the cavity should be chosen such that the buckled SMF is not mechanically confined to ensure buckling in a first-order mode. The optical bending loss in the buckled SMF is calculated using a fully vectorial mode solver, showing that a minimal buckling cavity length of 20 mm is necessary to keep the excess optical loss from bending below 0.1 dB. Both our optical and mechanical simulation results are experimentally verified.

Demonstration of Efficient Nonreciprocity in a Microwave Optomechanical Circuit*

NASA Astrophysics Data System (ADS)

Peterson, G. A.; Lecocq, F.; Cicak, K.; Simmonds, R. W.; Aumentado, J.; Teufel, J. D.

2017-07-01

The ability to engineer nonreciprocal interactions is an essential tool in modern communication technology as well as a powerful resource for building quantum networks. Aside from large reverse isolation, a nonreciprocal device suitable for applications must also have high efficiency (low insertion loss) and low output noise. Recent theoretical and experimental studies have shown that nonreciprocal behavior can be achieved in optomechanical systems, but performance in these last two attributes has been limited. Here, we demonstrate an efficient, frequency-converting microwave isolator based on the optomechanical interactions between electromagnetic fields and a mechanically compliant vacuum-gap capacitor. We achieve simultaneous reverse isolation of more than 20 dB and insertion loss less than 1.5 dB. We characterize the nonreciprocal noise performance of the device, observing that the residual thermal noise from the mechanical environments is routed solely to the input of the isolator. Our measurements show quantitative agreement with a general coupled-mode theory. Unlike conventional isolators and circulators, these compact nonreciprocal devices do not require a static magnetic field, and they allow for dynamic control of the direction of isolation. With these advantages, similar devices could enable programmable, high-efficiency connections between disparate nodes of quantum networks, even efficiently bridging the microwave and optical domains.

Ultra-wide tuning single channel filter based on one-dimensional photonic crystal with an air cavity

NASA Astrophysics Data System (ADS)

Zhao, Xiaodan; Yang, Yibiao; Chen, Zhihui; Wang, Yuncai; Fei, Hongming; Deng, Xiao

2017-02-01

By inserting an air cavity into a one-dimensional photonic crystal of LiF/GaSb, a tunable filter covering the whole visible range is proposed. Following consideration of the dispersion of the materials, through modulating the thickness of the air cavity, we demonstrate that a single resonant peak can shift from 416.1 to 667.3 nm in the band gap at normal incidence by means of the transfer matrix method. The research also shows that the transmittance of the channel can be maximized when the number of periodic LiF/GaSb layers on one side of the air defect layer is equal to that of the other side. When adding a period to both sides respectively, the full width at half maximum of the defect mode is reduced by one order of magnitude. This structure will provide a promising approach to fabricate practical tunable filters in the visible region with ultra-wide tuning range. Project supported by the National Natural Science Foundation of China (Nos. 61575138, 61307069, 51205273), and the Top Young Academic Leaders and the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi.

Reconfigurable optomechanical circulator and directional amplifier.

PubMed

Shen, Zhen; Zhang, Yan-Lei; Chen, Yuan; Sun, Fang-Wen; Zou, Xu-Bo; Guo, Guang-Can; Zou, Chang-Ling; Dong, Chun-Hua

2018-05-04

Non-reciprocal devices, which allow non-reciprocal signal routing, serve as fundamental elements in photonic and microwave circuits and are crucial in both classical and quantum information processing. The radiation-pressure-induced coupling between light and mechanical motion in travelling-wave resonators has been exploited to break the Lorentz reciprocity, enabling non-reciprocal devices without magnetic materials. Here, we experimentally demonstrate a reconfigurable non-reciprocal device with alternative functions as either a circulator or a directional amplifier via optomechanically induced coherent photon-phonon conversion or gain. The demonstrated device exhibits considerable flexibility and offers exciting opportunities for combining reconfigurability, non-reciprocity and active properties in single photonic devices, which can also be generalized to microwave and acoustic circuits.

Breakdown of Bose-Einstein Distribution in Photonic Crystals

PubMed Central

Lo, Ping-Yuan; Xiong, Heng-Na; Zhang, Wei-Min

2015-01-01

In the last two decades, considerable advances have been made in the investigation of nano-photonics in photonic crystals. Previous theoretical investigations of photon dynamics were carried out at zero temperature. Here, we investigate micro/nano cavity photonics in photonic crystals at finite temperature. Due to photonic-band-gap-induced localized long-lived photon dynamics, we discover that cavity photons in photonic crystals do not obey Bose-Einstein statistical distribution. Within the photonic band gap and in the vicinity of the band edge, cavity photons combine the long-lived non-Markovain dynamics with thermal fluctuations together to form photon states that memorize the initial cavity state information. As a result, Bose-Einstein distribution is completely broken down in these regimes, even if the thermal energy is larger or much larger than the cavity detuning energy. In this investigation, a crossover phenomenon from equilibrium to nonequilibrium steady states is also revealed. PMID:25822135

Topological Phases of Sound and Light

NASA Astrophysics Data System (ADS)

Peano, V.; Brendel, C.; Schmidt, M.; Marquardt, F.

2015-07-01

Topological states of matter are particularly robust, since they exploit global features of a material's band structure. Topological states have already been observed for electrons, atoms, and photons. It is an outstanding challenge to create a Chern insulator of sound waves in the solid state. In this work, we propose an implementation based on cavity optomechanics in a photonic crystal. The topological properties of the sound waves can be wholly tuned in situ by adjusting the amplitude and frequency of a driving laser that controls the optomechanical interaction between light and sound. The resulting chiral, topologically protected phonon transport can be probed completely optically. Moreover, we identify a regime of strong mixing between photon and phonon excitations, which gives rise to a large set of different topological phases and offers an example of a Chern insulator produced from the interaction between two physically distinct particle species, photons and phonons.

Focus and perspective adaptive digital surgical microscope: optomechanical design and experimental implementation

NASA Astrophysics Data System (ADS)

Claus, Daniel; Reichert, Carsten; Herkommer, Alois

2017-05-01

This paper relates to the improvement of conventional surgical stereo microscopy via the application of digital recording devices and adaptive optics. The research is aimed at improving the working conditions of the surgeon during the operation, such that free head movement is possible. The depth clues known from conventional stereo microscopy in interaction with the human eye's functionality, such as convergence, disparity, angular elevation, parallax, and accommodation, are implemented in a digital recording system via adaptive optomechanical components. Two laterally moving pupil apertures have been used mimicking the digital implementation of the eye's vergence and head motion. The natural eye's accommodation is mimicked via the application of a tunable lens. Additionally, another system has been built, which enables tracking the surgeon's eye pupil through a digital displaying stereoscopic microscope to supply the necessary information for steering the recording system. The optomechanical design and experimental results for both systems, digital recording stereoscopic microscope and pupil tracking system, are shown.

Optomechanical and thermal design of the Multi-Application Solar Telescope for USO

NASA Astrophysics Data System (ADS)

Denis, Stefan; Coucke, Pierre; Gabriel, Eric; Delrez, Christophe; Venkatakrishnan, Parameshwaran

2008-07-01

The Multi-Application Solar Telescope (MAST) is a 50 cm diameter class telescope to be installed on the Udaipur Solar Observatory's Island on the Lake Fatehsagar in Udaipur, India. It is dedicated to solar observation. The telescope is designed, manufactured, assembled and installed on-site by the belgian company AMOS SA for the Udaipur Solar Observatory (USO), an academic division of the Physical Research Laboratory (PRL) in India. Despite its limited size, the telescope is expected to be competitive with respect to worldwide large and costly projects thanks to its versatility regarding science goals and also thanks to its demanding optomechanical and thermal specification. This paper describes the optomechanical and thermal design of this telescope and presents solutions adopted by AMOS to meet the specific requirements. The optical configuration of the telescope is based on an afocal off-axis gregorian combination integrated on an Alt.-Az. mechanical mount, with a suite of flat folding mirrors to provide the required stationary collimated beam.

Injection locking of optomechanical oscillators via acoustic waves

NASA Astrophysics Data System (ADS)

Huang, Ke; Hossein-Zadeh, Mani

2018-04-01

Injection locking is a powerful technique for synchronization of oscillator networks and controlling the phase and frequency of individual oscillators using similar or other types of oscillators. Here, we present the first demonstration of injection locking of a radiation-pressure driven optomechanical oscillator (OMO) via acoustic waves. As opposed to previously reported techniques (based on pump modulation or direct application of a modulated electrostatic force), injection locking of OMO via acoustic waves does not require optical power modulation or physical contact with the OMO and it can easily be implemented on various platforms. Using this approach we have locked the phase and frequency of two distinct modes of a microtoroidal silica OMO to a piezoelectric transducer (PZT). We have characterized the behavior of the injection locked OMO with three acoustic excitation configurations and showed that even without proper acoustic impedance matching the OMO can be locked to the PZT and tuned over 17 kHz with only -30 dBm of RF power fed to the PZT. The high efficiency, simplicity and scalability of the proposed approach paves the road toward a new class of photonic systems that rely on synchronization of several OMOs to a single or multiple RF oscillators with applications in optical communication, metrology and sensing. Beyond its practical applications, injection locking via acoustic waves can be used in fundamental studies in quantum optomechanics where thermal and optical isolation of the OMO are critical.

Cavity-type hypersonic phononic crystals

NASA Astrophysics Data System (ADS)

Sato, A.; Pennec, Y.; Yanagishita, T.; Masuda, H.; Knoll, W.; Djafari-Rouhani, B.; Fytas, G.

2012-11-01

We report on the engineering of the phonon dispersion diagram in monodomain anodic porous alumina (APA) films through the porosity and physical state of the material residing in the nanopores. Lattice symmetry and inclusion materials are theoretically identified to be the main factors which control the hypersonic acoustic wave propagation. This involves the interaction between the longitudinal and the transverse modes in the effective medium and a flat band characteristic of the material residing in the cavities. Air and filled nanopores, therefore, display markedly different dispersion relations and the inclusion materials lead to a locally resonant structural behavior uniquely determining their properties under confinement. APA films emerge as a new platform to investigate the rich acoustic phenomena of structured composite matter.

Superharmonic resonances in a two-dimensional non-linear photonic-crystal nano-electro-mechanical oscillator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chowdhury, A.; Yeo, I.; Tsvirkun, V.

2016-04-18

We investigate the non-linear mechanical dynamics of a nano-optomechanical mirror formed by a suspended membrane pierced by a photonic crystal. By applying to the mirror a periodic electrostatic force induced by interdigitated electrodes integrated below the membrane, we evidence superharmonic resonances of our nano-electro-mechanical system; the constant phase shift of the oscillator across the resonance tongues is observed on the onset of principal harmonic and subharmonic excitation regimes.

Optical transmission properties of an anisotropic defect cavity in one-dimensional photonic crystal

NASA Astrophysics Data System (ADS)

Ouchani, Noama; El Moussaouy, Abdelaziz; Aynaou, Hassan; El Hassouani, Youssef; El Boudouti, El Houssaine; Djafari-Rouhani, Bahram

2018-01-01

We investigate theoretically the possibility to control the optical transmission in the visible and infrared regions by a defective one dimensional photonic crystal formed by a combination of a finite isotropic superlattice and an anisotropic defect layer. The Green's function approach has been used to derive the reflection and the transmission coefficients, as well as the densities of states of the optical modes. We evaluate the delay times of the localized modes and we compare their behavior with the total densities of states. We show that the birefringence of an anisotropic defect layer has a significant impact on the behavior of the optical modes in the electromagnetic forbidden bands of the structure. The amplitudes of the defect modes in the transmission and the delay time spectrum, depend strongly on the position of the cavity layer within the photonic crystal. The anisotropic defect layer induces transmission zeros in one of the two components of the transmission as a consequence of a destructive interference of the two polarized waves within this layer, giving rise to negative delay times for some wavelengths in the visible and infrared light ranges. This property is a typical characteristic of the anisotropic photonic layer and is without analogue in their counterpart isotropic defect layers. This structure offers several possibilities for controlling the frequencies, transmitted intensities and the delay times of the optical modes in the visible and infrared regions. It can be a good candidate for realizing high-precision optical filters.

Electrically tunable liquid crystal photonic bandgap fiber laser

NASA Astrophysics Data System (ADS)

Olausson, Christina B.; Scolari, Lara; Wei, Lei; Noordegraaf, Danny; Weirich, Johannes; Alkeskjold, Thomas T.; Hansen, Kim P.; Bjarklev, Anders

2010-02-01

We demonstrate electrical tunability of a fiber laser using a liquid crystal photonic bandgap fiber. Tuning of the laser is achieved by combining the wavelength filtering effect of a liquid crystal photonic bandgap fiber device with an ytterbium-doped photonic crystal fiber. We fabricate an all-spliced laser cavity based on a liquid crystal photonic bandgap fiber mounted on a silicon assembly, a pump/signal combiner with single-mode signal feed-through and an ytterbium-doped photonic crystal fiber. The laser cavity produces a single-mode output and is tuned in the range 1040- 1065 nm by applying an electric field to the silicon assembly.

Optimal estimation of the optomechanical coupling strength

NASA Astrophysics Data System (ADS)

Bernád, József Zsolt; Sanavio, Claudio; Xuereb, André

2018-06-01

We apply the formalism of quantum estimation theory to obtain information about the value of the nonlinear optomechanical coupling strength. In particular, we discuss the minimum mean-square error estimator and a quantum Cramér-Rao-type inequality for the estimation of the coupling strength. Our estimation strategy reveals some cases where quantum statistical inference is inconclusive and merely results in the reinforcement of prior expectations. We show that these situations also involve the highest expected information losses. We demonstrate that interaction times on the order of one time period of mechanical oscillations are the most suitable for our estimation scenario, and compare situations involving different photon and phonon excitations.

Kuznetsov-Ma Soliton Dynamics Based on the Mechanical Effect of Light

NASA Astrophysics Data System (ADS)

Xiong, Hao; Gan, Jinghui; Wu, Ying

2017-10-01

A Kuznetsov-Ma soliton that exhibits an unusual pulsating dynamics has attracted particular attention in hydrodynamics and plasma physics in the context of understanding nonlinear coherent phenomena. Here, we demonstrate theoretically the formation of a novel form of Kuznetsov-Ma soliton in a microfabricated optomechanical array, where both photonic and phononic evolutionary dynamics exhibit periodic structure and coherent localized behavior enabled by radiation-pressure coupling of optical fields and mechanical oscillations, which is a manifestation of the unique property of optomechanical systems. Numerical calculations of the optomechanical dynamics show an excellent agreement with this theory. In addition to providing insight into optomechanical nonlinearity, optomechanical Kuznetsov-Ma soliton dynamics fundamentally broadens the regime of cavity optomechanics and may find applications in on-chip manipulation of light propagation.

Optomechanical design of the vacuum compatible EXCEDE's mission testbed

NASA Astrophysics Data System (ADS)

Bendek, Eduardo A.; Belikov, Ruslan; Lozi, Julien; Schneider, Glenn; Thomas, Sandrine; Pluzhnik, Eugene; Lynch, Dana

2014-08-01

In this paper we describe the opto-mechanical design, tolerance error budget an alignment strategies used to build the Starlight Suppression System (SSS) for the Exoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) NASA's mission. EXCEDE is a highly efficient 0.7m space telescope concept designed to directly image and spatially resolve circumstellar disks with as little as 10 zodis of circumstellar dust, as well as large planets. The main focus of this work was the design of a vacuum compatible opto-mechanical system that allows remote alignment and operation of the main components of the EXCEDE. SSS, which are: a Phase Induced Amplitude Apodization (PIAA) coronagraph to provide high throughput and high contrast at an inner working angle (IWA) equal to the diffraction limit (IWA = 1.2 l/D), a wavefront (WF) control system based on a Micro-Electro-Mechanical-System deformable mirror (MEMS DM), and low order wavefront sensor (LOWFS) for fine pointing and centering. We describe in strategy and tolerance error budget for this system, which is especially relevant to achieve the theoretical performance that PIAA coronagraph can offer. We also discuss the vacuum cabling design for the actuators, cameras and the Deformable Mirror. This design has been implemented at the vacuum chamber facility at Lockheed Martin (LM), which is based on successful technology development at the Ames Coronagraph Experiment (ACE) facility.

Electromagnetic-continuum-induced nonlinearity

NASA Astrophysics Data System (ADS)

Matsko, Andrey B.; Vyatchanin, Sergey P.

2018-05-01

A nonrelativistic Hamiltonian describing interaction between a mechanical degree of freedom and radiation pressure is commonly used as an ultimate tool for studying system behavior in optomechanics. This Hamiltonian is derived from the equation of motion of a mechanical degree of freedom and the optical wave equation with time-varying boundary conditions. We show that this approach is deficient for studying higher-order nonlinear effects in an open resonant optomechanical system. Optomechanical interaction induces a large mechanical nonlinearity resulting from a strong dependence of the power of the light confined in the optical cavity on the mechanical degrees of freedom of the cavity due to coupling with electromagnetic continuum. This dissipative nonlinearity cannot be inferred from the standard Hamiltonian formalism.

Injection locking of optomechanical oscillators via acoustic waves.

PubMed

Huang, Ke; Hossein-Zadeh, Mani

2018-04-02

Injection locking is an effective technique for synchronization of oscillator networks and controlling the phase and frequency of individual oscillators. As such, exploring new mechanisms for injection locking of emerging oscillators is important for their usage in various systems. Here, we present the first demonstration of injection locking of a radiation pressure driven optomechanical oscillator (OMO) via acoustic waves. As opposed to previously reported techniques (based on pump modulation or direct application of a modulated electrostatic force), injection locking of OMO via acoustic waves does not require optical power modulation or physical contact with the OMO and it can be easily implemented on various platforms to lock different types of OMOs independent of their size and structure. Using this approach we have locked the phase and frequency of two distinct modes of a microtoroidal silica OMO to a piezoelectric transducer (PZT). We have characterized the behavior of the injection locked OMO with three acoustic excitation configurations and showed that even without proper acoustic impedance, matching the OMO can be locked to the PZT and tuned over 17 kHz with only -30 dBm of RF power fed to the PZT. The high efficiency, simplicity, and scalability of the proposed approach paves the road toward a new class of photonic systems that rely on synchronization of several OMOs to a single or multiple RF oscillators with applications in optical communication, metrology, and sensing. Beyond its practical applications, injection locking via acoustic waves can be used in fundamental studies in quantum optomechanics where thermal and optical isolation of the OMO are critical.

Mineralogy and provenance of clays in miarolitic cavities of the Pikes Peak Batholith, Colorado

USGS Publications Warehouse

Kile, D.E.

2005-01-01

Clay samples from 105 cavities within miarolitic granitic pegmatites throughout the Pikes Peak batholith, in Colorado, were analyzed by powder X-ray diffraction (XRD). Smectite (beidellite), illite, and kaolinite were found within the cavities. Calculation of crystallite-thickness distribution (CTD), mean thickness of the crystallites, and variance in crystallite thickness, as deduced from XRD patterns, allowed a determination of provenance and mode of formation for illite and smectite. Authigenic miarolitic-cavity illite and smectite show lognormal CTDs and larger mean thicknesses of crystallites than do their soil-derived counterparts; non-lognormal illite in a cavity results from mixing of cavity and soil illite. Analysis of mean thickness and thickness variance shows that crystal growth of illite is initiated by a nucleation event of short duration, followed by surface-controlled kinetics. Crystallization of the miarolitic cavity clays is presumed to occur by neoformation from hydrothermal fluids. The assessment of provenance allows a determination of regional and local distributions of clay minerals in miarolitic cavities within the Pikes Peak batholith.

Hybrid photonic-plasmonic crystal nanocavity sensors

NASA Astrophysics Data System (ADS)

Cheng, Pi-Ju; Chiang, Chih-Kai; Chou, Bo-Tsun; Huang, Zhen-Ting; Ku, Yun-Cheng; Kuo, Mao-Kuen; Hsu, Jin-Chen; Lin, Tzy-Rong

2018-02-01

We have investigated a hybrid photonic-plasmonic crystal nanocavity consisting of a silicon grating nanowire adjacent to a metal surface with a gain gap between them. The hybrid plasmonic cavity modes are highly confined in the gap due to the strong coupling of the photonic crystal cavity modes and the surface plasmonic gap modes. Using finite-element method (FEM), guided modes of the hybrid plasmonic waveguide (WG) were numerically determined at a wavelength of 1550 nm. The modal characteristics such as WG confinement factors and modal losses of the fundamental hybrid plasmonic modes were obtained as a function of groove depth at various gap heights. Furthermore, the band structure of the hybrid crystal modes corresponding to a wide band gap of 17.8 THz is revealed. To enclose the optical energy effectively, a single defect was introduced into the hybrid crystal. At a deep subwavelength defect length as small as 270 nm, the resonant mode exhibits a high quality factor of 567 and an ultrasmall mode volume of 1.9 × 10- 3 ( λ/ n eff)3 at the resonance wavelength of 1550 nm. Compared to conventional photonic crystal nanowire cavities in the absence of a metal surface, the factor Q/ V m is significantly enhanced by about 15 times. The designed hybrid photonic-plasmonic cavity sensors exhibit distinguished characteristics such as sensitivity of 443 nm/RIU and figure of merit of 129. The proposed nanocavities open new possibilities for various applications with strong light-matter interaction, such as biosensors and nanolasers.

Advances in Large Grain/Single Crystal SC Resonators at DESY

DOE Office of Scientific and Technical Information (OSTI.GOV)

W. Singer; A. Brinkmann; A. Ermakov

The main aim of the DESY large grain R&D program is to check whether this option is reasonable to apply for fabrication of ca. 1'000 XFEL cavities. Two aspects are being pursued. On one hand the basic material investigation, on the other hand the material availability, fabrication and preparation procedure. Several single cell large grain cavities of TESLA shape have been fabricated and tested. The best accelerating gradients of 41 MV/m was measured on electropolished cavity. First large grain nine-cell cavities worldwide have been produced under contract of DESY with ACCEL Instruments Co. All three cavities fulfil the XFEL specificationmore » already in first RF test after only BCP (Buffered Chemical Polishing) treatment and 800 degrees C annealing. Accelerating gradient of 27 - 29 MV/m was reached. A fabrication method of single crystal cavity of ILC like shape was proposed. A single cell single crystal cavity was build at the company ACCEL. Accelerating gradient of 37.5 MV/m reached after only 112 microns BCP and in situ baking 120 degrees C for 6 hrs with the quality factor higher as 2x1010. The developed method can be extended on fabrication of multi cell single crystal cavities.« less

Apparatus And Method For Producing Single Crystal Metallic Objects

DOEpatents

Huang, Shyh-Chin; Gigliotti, Jr., Michael Francis X.; Rutkowski, Stephen Francis; Petterson, Roger John; Svec, Paul Steven

2006-03-14

A mold is provided for enabling casting of single crystal metallic articles including a part-defining cavity, a sorter passage positioned vertically beneath and in fluid communication with the part-defining cavity, and a seed cavity positioned vertically beneath and in fluid communication with the sorter passage. The sorter passage includes a shape suitable for encouraging a single crystal structure in solidifying molten metal. Additionally, a portion of the mold between the sorter passage and the part-defining cavity includes a notch for facilitating breakage of a cast article proximate the notch during thermal stress build-up, so as to prevent mold breakage or the inclusion of part defects.

Entanglement manipulation via Coulomb interaction in an optomechanical cavity assisted by two-level cold atoms

NASA Astrophysics Data System (ADS)

Wang, Jing; Tian, Xue-Dong; Liu, Yi-Mou; Cui, Cui-Li; Wu, Jin-Hui

2018-06-01

We investigate the stationary entanglement properties in a hybrid system consisting of an optical cavity, a mechanical resonator, a charged object, and an atomic ensemble. Numerical results show that this hybrid system exhibits three kinds of controllable bipartite entanglements in an experimentally accessible parameter regime with the help of the charged object. More importantly, it is viable to enhance on demand each bipartite entanglement at the expense of reducing others by modulating the Coulomb coupling strength. Last but not least, these bipartite entanglements seem more robust against on the environmental temperature for the positive Coulomb interaction.

Efficiency of different methods of extra-cavity second harmonic generation of continuous wave single-frequency radiation.

PubMed

Khripunov, Sergey; Kobtsev, Sergey; Radnatarov, Daba

2016-01-20

This work presents for the first time to the best of our knowledge a comparative efficiency analysis among various techniques of extra-cavity second harmonic generation (SHG) of continuous-wave single-frequency radiation in nonperiodically poled nonlinear crystals within a broad range of power levels. Efficiency of nonlinear radiation transformation at powers from 1 W to 10 kW was studied in three different configurations: with an external power-enhancement cavity and without the cavity in the case of single and double radiation pass through a nonlinear crystal. It is demonstrated that at power levels exceeding 1 kW, the efficiencies of methods with and without external power-enhancement cavities become comparable, whereas at even higher powers, SHG by a single or double pass through a nonlinear crystal becomes preferable because of the relatively high efficiency of nonlinear transformation and fairly simple implementation.

Mechanical properties of niobium radio-frequency cavities

DOE PAGES

Ciovati, Gianluigi; Dhakal, Pashupati; Matalevich, Joseph R.; ...

2015-07-02

Radio-frequency cavities made of bulk niobium are one of the components used in modern particle accelerators. The mechanical stability is an important aspect of cavity design, which typically relies on finite-element analysis simulations using material properties from tensile tests on sample. This contribution presents the results of strain and resonant frequency measurements as a function of a uniform pressure up to 722 kPa, applied to single-cell niobium cavities with different crystallographic structure, purity and treatments. In addition, burst tests of high-purity multi-cell cavities with different crystallographic structure have been conducted up to the tensile strength of the material. Finite-element analysismore » of the single-cell cavity geometry is in good agreement with the observed behavior in the elastic regime assuming a Young's modulus value of 88.5 GPa and a Poisson's ratio of 0.4, regardless of crystallographic structure, purity or treatment. However, the measured yield strength and tensile strength depend on crystallographic structure, material purity and treatment. In particular, the results from this study show that the mechanical properties of niobium cavities with large crystals are comparable to those of cavities made of fine-grain niobium.« less

Spectral Engineering of Slow Light, Cavity Line Narrowing, and Pulse Compression

NASA Astrophysics Data System (ADS)

Sabooni, Mahmood; Li, Qian; Rippe, Lars; Mohan, R. Krishna; Kröll, Stefan

2013-11-01

More than 4 orders of magnitude of cavity-linewidth narrowing in a rare-earth-ion-doped crystal cavity, emanating from strong intracavity dispersion caused by off-resonant interaction with dopant ions, is demonstrated. The dispersion profiles are engineered using optical pumping techniques creating significant semipermanent but reprogrammable changes of the rare-earth absorption profiles. Several cavity modes are shown within the spectral transmission window. Several possible applications of this phenomenon are discussed.

Suppression of Laser Shot Noise Using Laser-Cooled OptoMechanical Systems

DTIC Science & Technology

2010-04-22

that this device will be able to demonstrate squeezing in a fairly short time . Background: The goal of this effort was to create laser light with...The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing...REPORT Final report on Seedling project: "Suppression of Laser Shot Noise Using Laser -Cooled Opto-Mechanical Systems" 14. ABSTRACT 16. SECURITY

Considerations for opto-mechanical vs. digital stabilization in surveillance systems

NASA Astrophysics Data System (ADS)

Kowal, David

2015-05-01

Electro-optical surveillance and reconnaissance systems are frequently mounted on unstable or vibrating platforms such as ships, vehicles, aircraft and masts. Mechanical coupling between the platform and the cameras leads to angular vibration of the line of sight. Image motion during detector and eye integration times leads to image smear and a resulting loss of resolution. Additional effects are wavy images for detectors based on a rolling shutter mechanism and annoying movement of the image at low frequencies. A good stabilization system should yield sub-pixel stabilization errors and meet cost and size requirements. There are two main families of LOS stabilization methods: opto-mechanical stabilization and electronic stabilization. Each family, or a combination of both, can be implemented by a number of different techniques of varying complexity, size and cost leading to different levels of stabilization. Opto-mechanical stabilization is typically based on gyro readings, whereas electronic stabilization is typically based on gyro readings or image registration calculations. A few common stabilization techniques, as well as options for different gimbal arrangements will be described and analyzed. The relative merits and drawbacks of the different techniques and their applicability to specific systems and environments will be discussed. Over the years Controp has developed a large number of stabilized electro-optical payloads. A few examples of payloads with unique stabilization mechanisms will be described.

Brownian Thermal Noise in Interferometric Gravitational Wave Detectors and Single Photon Optomechanics

NASA Astrophysics Data System (ADS)

Hong, Ting

. For the future GW detectors, with much lower noises and higher sensitivity, this might be used to investigate the quantum behaviors of macroscopic mechanical objects. In recent years the linear optomechanical systems with cavity modes coupling to a mechanical oscillator have been studied extensively. In the second part of my thesis (Chapter 4), I study the interaction between a single photon and a high-finesse cavity with a movable mirror, in the so-called strong coupling regime, where the recoil of the photon can cause significant change in the momentum of the mirror. The results are applied to analyze the case with a Fabry-Perot cavity. We also present that with engineering the photon wave function, it is possible to prepare the oscillator into an arbitrary quantum state.

Single-crystal diamond nanomechanical resonators with quality factors exceeding one million

NASA Astrophysics Data System (ADS)

Tao, Y.; Boss, J. M.; Moores, B. A.; Degen, C. L.

2014-04-01

Diamond has gained a reputation as a uniquely versatile material, yet one that is intricate to grow and process. Resonating nanostructures made of single-crystal diamond are expected to possess excellent mechanical properties, including high-quality factors and low dissipation. Here we demonstrate batch fabrication and mechanical measurements of single-crystal diamond cantilevers with thickness down to 85 nm, thickness uniformity better than 20 nm and lateral dimensions up to 240 μm. Quality factors exceeding one million are found at room temperature, surpassing those of state-of-the-art single-crystal silicon cantilevers of similar dimensions by roughly an order of magnitude. The corresponding thermal force noise for the best cantilevers is ~5·10-19 N Hz-1/2 at millikelvin temperatures. Single-crystal diamond could thus directly improve existing force and mass sensors by a simple substitution of resonator material. Presented methods are easily adapted for fabrication of nanoelectromechanical systems, optomechanical resonators or nanophotonic devices that may lead to new applications in classical and quantum science.

Beyond mean-field effects in Bloch Oscillations of cold atoms in an optical cavity

NASA Astrophysics Data System (ADS)

Venkatesh Balasubramanian, Prasanna; O'Dell, Duncan

2012-06-01

In our earlier publication [1] we proposed using Bloch oscillations of cold atoms inside an Fabry-Perot resonator for sensitive measurements of force. The analysis in [1] was performed using a coherent mean-field description for the atoms and the light. In the current work we extend this description substantially by including the effects of fluctuations in both the atomic and light fields. This analysis is used to set realistic limits on the precision to which the force can be measured. We also make contact with the optomechanical description of the combined atom-cavity system which has proved so successful for describing recent pioneering experiments [2].[4pt] [1] B. Prasanna Venkatesh et al, Phys. Rev. A 80, 063834 (2009).[0pt] [2] S. Gupta et al, Phys. Rev. Lett. 99, 213601 (2007); F.Brennecke et al, Science 322, 235 (2008).

Opto-mechanical design of a dispersive artificial eye.

PubMed

Coughlan, Mark F; Mihashi, Toshifumi; Goncharov, Alexander V

2017-05-20

We present an opto-mechanical artificial eye that can be used for examining multi-wavelength ophthalmic instruments. Standard off-the-shelf lenses and a refractive-index-matching fluid were used in the creation of the artificial eye. In addition to dispersive properties, the artificial eye can be used to simulate refractive error. To analyze the artificial eye, a multi-wavelength Hartmann-Shack aberrometer was used to measure the longitudinal chromatic aberration and the possibility of inducing refractive error. Off-axis chromatic aberrations were also analyzed by imaging through the artificial eye at two discrete wavelengths. Possible extensions to the dispersive artificial eye are also discussed.

Study of Etching Pits in a Large-grain Single Cell Bulk Niobium Cavity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Xin; Ciovati, Gianluigi; Reece, Charles E.

2009-11-01

Performance of SRF cavities are limited by non-linear localized effects. The variation of local material characters between "hot" and "cold" spots is thus of intense interest. Such locations were identified in a BCP-etched large-grain single-cell cavity and removed for examination by high resolution electron microscopy (SEM), electron-back scattering diffraction microscopy (EBSD), optical microscopy, and 3D profilometry. Pits with clearly discernable crystal facets were observed in both "hotspot" and "coldspot" specimens. The pits were found in-grain, at bi-crystal boundaries, and on tri-crystal junctions. They are interpreted as etch pits induced by surface crystal defects (e.g. dislocations). All "coldspots" examined had qualitativelymore » low density of etching pits or very shallow tri-crystal boundary junction. EBSD revealed crystal structure surrounding the pits via crystal phase orientation mapping, while 3D profilometry gave information on the depth and size of the pits. In addition, a survey of the samples by energy dispersive X-ray analysis (EDX) did not show any significant contamination of the samples surface.« less

Opto-Mechanics of the Constellation-X SXT Mirrors: Challenges in Mounting and Assembling the Mirror Segments

NASA Technical Reports Server (NTRS)

Chan, Kai-Wing; Zhang, WIlliam W.; Saha, Timo; Lehan, John P.; Mazzarella, James; Lozipone, Lawrence; Hong, Melinda; Byron, Glenn

2008-01-01

The Constellation-X Spectroscopy X-Ray Telescopes consists of segmented glass mirrors with an axial length of 200 mm, a width of up to 400 mm, and a thickness of 0.4 mm. To meet the requirement of less than 15 arc-second half-power diameter with the small thickness and relatively large size is a tremendous challenge in opto-mechanics. How shall we limit distortion of the mirrors due to gravity in ground tests, that arises from thermal stress, and that occurs in the process of mounting, affixing and assembling of these mirrors? In this paper, we will describe our current opto-mechanical approach to these problems. We will discuss, in particular, the approach and experiment where the mirrors are mounted vertically by first suspending it at two points.

The opto-mechanical design for GMOX: a next-generation instrument concept for Gemini

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Barkhouser, Robert; Robberto, Massimo; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy M.

2016-08-01

We present the opto-mechanical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph, a potential next-generation (Gen-4 #3) facility-class instrument for Gemini. GMOX is a wide-band, multi-object, spectrograph with spectral coverage spanning 350 nm to 2.4 um with a nominal resolving power of R 5000. Through the use of Digital Micromirror Device (DMD) technology, GMOX will be able to acquire spectra from hundreds of sources simultaneously, offering unparalleled flexibility in target selection. Utilizing this technology, GMOX can rapidly adapt individual slits to either seeing-limited or diffraction-limited conditions. The optical design splits the bandpass into three arms, blue, red, and near infrared, with the near-infrared arm being split into three channels covering the Y+J band, H band, and K band. A slit viewing camera in each arm provides imaging capability for target acquisition and fast-feedback for adaptive optics control with either ALTAIR (Gemini North) or GeMS (Gemini South). Mounted at the Cassegrain focus, GMOX is a large (1.3 m x 2.8 m x 2.0 m) complex instrument, with six dichroics, three DMDs (one per arm), five science cameras, and three acquisition cameras. Roughly half of these optics, including one DMD, operate at cryogenic temperature. To maximize stiffness and simplify assembly and alignment, the opto-mechanics are divided into three main sub-assemblies, including a near-infrared cryostat, each having sub-benches to facilitate ease of alignment and testing of the optics. In this paper we present the conceptual opto-mechanical design of GMOX, with an emphasis on the mounting strategy for the optics and the thermal design details related to the near-infrared cryostat.

Nonlinear response of silicon photonic crystal microresonators excited via an integrated waveguide and fiber taper.

PubMed

Barclay, Paul; Srinivasan, Kartik; Painter, Oskar

2005-02-07

A technique is demonstrated which efficiently transfers light between a tapered standard single-mode optical fiber and a high-Q, ultra-small mode volume, silicon photonic crystal resonant cavity. Cavity mode quality factors of 4.7x10(4) are measured, and a total fiber-to-cavity coupling efficiency of 44% is demonstrated. Using this efficient cavity input and output channel, the steady-state nonlinear absorption and dispersion of the photonic crystal cavity is studied. Optical bistability is observed for fiber input powers as low as 250 microW, corresponding to a dropped power of 100 microW and 3 fJ of stored cavity energy. A high-density effective free-carrier lifetime for these silicon photonic crystal resonators of ~ 0.5 ns is also estimated from power dependent loss and dispersion measurements.

Optomechanical detection of weak microwave signals with the assistance of a plasmonic wave

NASA Astrophysics Data System (ADS)

Nejad, A. Asghari; Askari, H. R.; Baghshahi, H. R.

2018-05-01

Entanglement between optical fields and microwave signals can be used as a quantum optical sensing technique to detect received microwave signals from a low-reflecting object which is encompassed by a bright thermal environment. Here, we introduce and analyze an optomechanical system for detecting weak reflected microwave signals from an object of low reflectivity. In our system, coupling and consequently entanglement between microwave and optical photons are achieved by means of a plasmonic wave. The main problem that can be moderated in the field of quantum optical sensing of weak microwave signals is suppressing the destructive effect of high temperatures on the entanglement between microwave signals and optical photons. For this purpose, we will show that our system can perform at high temperatures as well as low ones. It will be shown that the presence of the plasmonic wave can reduce the destructive effect of the thermal noises on the entanglement between microwave and optical photons. Also, we will show that the optomechanical interaction is vital to create an appropriate entanglement between microwave and optical photons.

Quantum-coherent coupling of a mechanical oscillator to an optical cavity mode.

PubMed

Verhagen, E; Deléglise, S; Weis, S; Schliesser, A; Kippenberg, T J

2012-02-01

Optical laser fields have been widely used to achieve quantum control over the motional and internal degrees of freedom of atoms and ions, molecules and atomic gases. A route to controlling the quantum states of macroscopic mechanical oscillators in a similar fashion is to exploit the parametric coupling between optical and mechanical degrees of freedom through radiation pressure in suitably engineered optical cavities. If the optomechanical coupling is 'quantum coherent'--that is, if the coherent coupling rate exceeds both the optical and the mechanical decoherence rate--quantum states are transferred from the optical field to the mechanical oscillator and vice versa. This transfer allows control of the mechanical oscillator state using the wide range of available quantum optical techniques. So far, however, quantum-coherent coupling of micromechanical oscillators has only been achieved using microwave fields at millikelvin temperatures. Optical experiments have not attained this regime owing to the large mechanical decoherence rates and the difficulty of overcoming optical dissipation. Here we achieve quantum-coherent coupling between optical photons and a micromechanical oscillator. Simultaneously, coupling to the cold photon bath cools the mechanical oscillator to an average occupancy of 1.7 ± 0.1 motional quanta. Excitation with weak classical light pulses reveals the exchange of energy between the optical light field and the micromechanical oscillator in the time domain at the level of less than one quantum on average. This optomechanical system establishes an efficient quantum interface between mechanical oscillators and optical photons, which can provide decoherence-free transport of quantum states through optical fibres. Our results offer a route towards the use of mechanical oscillators as quantum transducers or in microwave-to-optical quantum links.

Quantum Control of a Spin Qubit Coupled to a Photonic Crystal Cavity

DTIC Science & Technology

2012-12-01

Cavities in Monocrystalline Diamond. Physical Review Letters 109, 033604 (2012). 14. Kroutvar, M. et al. Optically programmable electron spin...temperatures, varying the detuning of X− from the cavity. The dashed blue lines in panel a are fits to the reflectivity. The spectra are vertically

Trapping virtual pores by crystal retro-engineering

NASA Astrophysics Data System (ADS)

Little, Marc A.; Briggs, Michael E.; Jones, James T. A.; Schmidtmann, Marc; Hasell, Tom; Chong, Samantha Y.; Jelfs, Kim E.; Chen, Linjiang; Cooper, Andrew I.

2015-02-01

Stable guest-free porous molecular crystals are uncommon. By contrast, organic molecular crystals with guest-occupied cavities are frequently observed, but these cavities tend to be unstable and collapse on removal of the guests—this feature has been referred to as ‘virtual porosity’. Here, we show how we have trapped the virtual porosity in an unstable low-density organic molecular crystal by introducing a second molecule that matches the size and shape of the unstable voids. We call this strategy ‘retro-engineering’ because it parallels organic retrosynthetic analysis, and it allows the metastable two-dimensional hexagonal pore structure in an organic solvate to be trapped in a binary cocrystal. Unlike the crystal with virtual porosity, the cocrystal material remains single crystalline and porous after removal of guests by heating.

Opto-mechanical design of a buckling cavity in a novel high-performance outside-plant robust field installable single-mode fibre connector

NASA Astrophysics Data System (ADS)

Ebraert, Evert; Van Erps, Jürgen; Beri, Stefano; Watté, Jan; Thienpont, Hugo

2014-05-01

Fibre-to-the-home (FTTH) networks provide an ideal means to reach the goal the European Union has set to provide 50 % of the households with a broadband connection faster than 100 Mb/s. Deployment of FTTH networks, which is still costly today, could be significantly boosted by novel ferrule-less connectors which don't require highly skilled personnel and allow installation in the field. We propose a ferrule-less connector in which two single-mode fibres (SMFs) are aligned and maintain physical contact by ensuring that at least one fibre is in a buckled state. To this end, we design a cavity in which a fibre can buckle in a controlled way. Using finite element analysis simulations to investigate the shape of the formed buckle for various buckling cavity lengths, we show that it can be accurately approximated by a cosine function. In addition, the optical performance of a buckled SMF is investigated by bending loss calculations and simulations. We show a good agreement between the analytical and the simulated bending loss results for a G.652 fibre at a wavelength of 1550 nm. Buckling cavity lengths smaller than 20 mm should be avoided to keep the optical bending loss due to buckling below 0.1 dB. In this case the cavity height should at least be 2 mm to avoid mechanical confinement of the fibre.

Polarized micro-cavity organic light-emitting devices.

PubMed

Park, Byoungchoo; Kim, Mina; Park, Chan Hyuk

2009-04-27

We present the results of a study of light emissions from a polarized micro-cavity Organic Light-Emitting Device (OLED), which consisted of a flexible, anisotropic one-dimensional (1-D) photonic crystal (PC) film substrate. It is shown that luminous Electroluminescent (EL) emissions from the polarized micro-cavity OLED were produced at relatively low operating voltages. It was also found that the peak wavelengths of the emitted EL light corresponded to the two split eigen modes of the high-energy band edges of the anisotropic PC film, with a strong dependence on the polarization state of the emitting light. For polarization along the ordinary axis of the anisotropic PC film, the optical split micro-cavity modes occurred at the longer high-energy photonic band gap (PBG) edge, while for polarization along the extraordinary axis, the split micro-cavity modes occurred at the shorter high-energy PBG edge, with narrow bandwidths. We demonstrated that the polarization and emission mode of the micro-cavity OLED may be selected by choosing the appropriate optical axis of the anisotropic 1-D PC film.

Enhancement of Raman scattering from monolayer graphene by photonic crystal nanocavities

NASA Astrophysics Data System (ADS)

Kimura, Issei; Yoshida, Masahiro; Sota, Masaki; Inoue, Taiki; Chiashi, Shohei; Maruyama, Shigeo; Kato, Yuichiro K.

Monolayer graphene is an atomically thin two-dimensional material that shows strong Raman scattering, while photonic crystal nanocavities with small mode volumes allow for efficient optical coupling at the nanoscale. Here we demonstrate resonant enhancement of graphene Raman G' band by coupling to photonic crystal cavity modes. Hexagonal-lattice photonic crystal L3 cavities are fabricated from silicon-on-insulator substrates. and monolayer graphene sheets grown by chemical vapor deposition are transferred onto the nanocavities. Excitation wavelength dependence of Raman spectra show that the Raman intensity is enhanced when the G' peak is in resonance with the cavity mode. By performing imaging measurements, we confirm that such an enhancement is only observed at the cavity position. Work supported by JSPS KAKENHI Grant Numbers JP16K13613, JP25107002 and MEXT (Photon Frontier Network Program, Nanotechnology Platform).

Control of slow-to-fast light and single-to-double optomechanically induced transparency in a compound resonator system: A theoretical approach

NASA Astrophysics Data System (ADS)

Ziauddin; Rahman, Mujeeb ur; Ahmad, Iftikhar; Qamar, Sajid

2017-10-01

The transmission characteristics of probe light field is investigated theoretically in a compound system of two coupled resonators. The proposed system consisted of two high-Q Fabry-Perot resonators in which one of the resonators is optomechanical. Optomechanically induced transparency (OMIT), having relatively large window, is noticed via strong coupling between the two resonators. We investigate tunable switching from single to double OMIT by increasing amplitude of the pump field. We notice that, control of slow and fast light can be obtained via the coupling strength between the two resonators.

Opto-mechanical support services. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This subcontract was for Optomec`c support of the Los Alamos National Laboratory`s (LANL`s) Group MEE-12 in the technical specialty area of opto-mechanical design, engineering and fabrication. Two individual tasks were defined by MEE-12 and completed by Optomec personnel. Edward J. Yavornik acted as Principal Investigator on the Wire and Fluorescent Fiber Offset Grid (WAFFOG) for the Neutral Particle Beam (NPB) GTA (Ground Test Accelerator) Experiment, and Thomas Swann acted as Principal Investigator on the ESS-7 Photometers Project. Some hardware was procured/fabricated for the ESS-7 Photometer task, however, most of the work consisted of design and engineering support resulting in drawingsmore » and specifications which were prepared by MEE-12 personnel. There were no technical papers or patents generated by Optomec personnel as a result of this work, and all work defined in the contract was completed.« less

Opto-mechanical architecture of the LISA instrument

NASA Astrophysics Data System (ADS)

Weise, Dennis; Marenaci, Pierangelo; Weimer, Peter; Berger, Marcel; Schulte, Hans R.; Gath, Peter; Johann, Ulrich

2017-11-01

We report on the latest iteration of the baseline opto-mechanical architecture of the LISA instru- ment, which has been developed within the current LISA Mission Formulation study under ESA con- tract. The collective features of the current architec- ture have been consolidated in an extensive trade of various alternative payload configurations, including variants with only one active proof mass per space- craft and the application of "In-Field Pointing" for accommodation of constellation breathing. With respect to the original configuration [1], the newly established architecture most notably distin- guishes itself by the use of an off-axis telescope and a "non-frequency-swap" science interferometer for stray light mitigation, as well as the implementa- tion of ancillary pathlength metrology in terms of an "Optical Truss" and Point Ahead Angle sensing.

Effect of electric field and temperature gradient on the orientational dynamics of liquid crystals in a microvolume cylindrical cavity.

PubMed

Zakharov, A V; Vakulenko, A A; Romano, Silvano

2009-10-28

We have considered a homogeneously aligned liquid crystal (HALC) microvolume confined between two infinitely long horizontal coaxial cylinders and investigated dynamic field pumping, i.e., studied the interactions between director, velocity, and electric E fields as well as a radially applied temperature gradient inverted Delta T, where the inner cylinder is kept at a lower temperature than the outer one. In order to elucidate the role of inverted Delta T in producing hydrodynamic flow u, we have carried out a numerical study of a system of hydrodynamic equations including director reorientation, fluid flow, and temperature redistribution across the HALC cavity. Calculations show that only under the influence of inverted Delta T does the initially quiescent HALC sample settle down to a stationary flow regime with horizontal component of velocity u(eq)(r). The effects of inverted Delta T and of the size of the HALC cavity on magnitude and direction of u(eq)(r) have been investigated for a number of hydrodynamic regimes. Calculations also showed that E influences only the director redistribution across the HALC but not the magnitude of the velocity u(eq)(r).

Multiple period s-p hybridization in nano-strip embedded photonic crystal.

PubMed

Han, Seunghoon; Lee, Il-Min; Kim, Hwi; Lee, Byoungho

2005-04-04

We report and analyze hybridization of s-state and p-state modes in photonic crystal one-dimensional defect cavity array. When embedding a nano-strip into a dielectric rod photonic crystal, an effective cavity array is made, where each cavity possesses two cavity modes: s-state and p-state. The two modes are laterally even versus the nano-strip direction, and interact with each other, producing defect bands, of which the group velocity becomes zero within the first Brillouin zone. We could model and describe the phenomena by using the tight-binding method, well agreeing with the plane-wave expansion method analysis. We note that the reported s- and p-state mode interaction corresponds to the hybridization of atomic orbital in solid-state physics. The concept of multiple period s-p hybridization and the proposed model can be useful for analyzing and developing novel photonic crystal waveguides and devices.

Light funneling from a photonic crystal laser cavity to a nano-antenna: overcoming the diffraction limit in optical energy transfer down to the nanoscale.

PubMed

Mivelle, Mathieu; Viktorovitch, Pierre; Baida, Fadi I; El Eter, Ali; Xie, Zhihua; Vo, Than-Phong; Atie, Elie; Burr, Geoffrey W; Nedeljkovic, Dusan; Rauch, Jean-Yves; Callard, Ségolène; Grosjean, Thierry

2014-06-16

We show that the near-field coupling between a photonic crystal microlaser and a nano-antenna can enable hybrid photonic systems that are both physically compact (free from bulky optics) and efficient at transferring optical energy into the nano-antenna. Up to 19% of the laser power from a micron-scale photonic crystal laser cavity is experimentally transferred to a bowtie aperture nano-antenna (BNA) whose area is 400-fold smaller than the overall emission area of the microlaser. Instead of a direct deposition of the nano-antenna onto the photonic crystal, it is fabricated at the apex of a fiber tip to be accurately placed in the microlaser near-field. Such light funneling within a hybrid structure provides a path for overcoming the diffraction limit in optical energy transfer to the nanoscale and should thus open promising avenues in the nanoscale enhancement and confinement of light in compact architectures, impacting applications such as biosensing, optical trapping, local heating, spectroscopy, and nanoimaging.

Cavity-enhanced generation of 6 W cw second-harmonic power at 532 nm in periodically-poled MgO:LiTaO3.

PubMed

Ricciardi, Iolanda; De Rosa, Maurizio; Rocco, Alessandra; Ferraro, Pietro; De Natale, Paolo

2010-05-24

We report on efficient cw high-power second harmonic generation in a periodically poled LiTaO3 crystal placed in a resonant enhancement cavity. We tested three configurations, differing in the coupling mirror reflectivity, and a maximum conversion efficiency of about 76%, corresponding to 6.1 W of green light with 8.0 W of fundamental power, was achieved. This is, to the best of our knowledge, the highest cw power ever reported using a periodically-poled crystal in an external cavity. We observed photo-thermal effect induced by photon absorption at the mirrors and in the crystal, which however does not affect stable operation of the cavity. A further effect arises for two out of the three configurations, at higher values of the input power, which degrades the performance of the locked cavity. We suggest this effect is due to the onset of competing nonlinearities in the same crystal.

High-temperature morphological evolution of lithographically introduced cavities in silicon carbide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narushima, Takayuki; Glaeser, Andreas M.

2000-12-01

Internal cavities of controlled geometry and crystallography were introduced in 6H silicon carbide single crystals by combining lithographic methods, ion beam etching, and solid-state diffusion bonding. The morphological evolution of these internal cavities (negative crystals) in response to anneals of up to 128 h duration at 1900 degrees C was examined using optical microscopy. Surface energy anisotropy and faceting have a strong influence on both the geometric and kinetic characteristics of evolution. Decomposition of 12{bar 1}0 cavity edges into 101{bar 0} facets was observed after 16 h anneals, indicating that 12{bar 1}0 faces are not components of the Wulff shape.more » The shape evolution kinetics of penny-shaped cavities were also investigated. Experimentally observed evolution rates decreased much more rapidly with those predicted by a model in which surface diffusion is assumed to be rate-limiting. This suggests that the development of facets, and the associated loss of ledges and terraces during the initial stages of evolution results in an evolution process limited by the nucleation rate of attachment/detachment sites (ledges) on the facets.« less

Opto-mechanical design of an image slicer for the GRIS spectrograph at GREGOR

NASA Astrophysics Data System (ADS)

Vega Reyes, N.; Esteves, M. A.; Sánchez-Capuchino, J.; Salaun, Y.; López, R. L.; Gracia, F.; Estrada Herrera, P.; Grivel, C.; Vaz Cedillo, J. J.; Collados, M.

2016-07-01

An image slicer has been proposed for the Integral Field Spectrograph [1] of the 4-m European Solar Telescope (EST) [2] The image slicer for EST is called MuSICa (Multi-Slit Image slicer based on collimator-Camera) [3] and it is a telecentric system with diffraction limited optical quality offering the possibility to obtain high resolution Integral Field Solar Spectroscopy or Spectro-polarimetry by coupling a polarimeter after the generated slit (or slits). Considering the technical complexity of the proposed Integral Field Unit (IFU), a prototype has been designed for the GRIS spectrograph at GREGOR telescope at Teide Observatory (Tenerife), composed by the optical elements of the image slicer itself, a scanning system (to cover a larger field of view with sequential adjacent measurements) and an appropriate re-imaging system. All these subsystems are placed in a bench, specially designed to facilitate their alignment, integration and verification, and their easy installation in front of the spectrograph. This communication describes the opto-mechanical solution adopted to upgrade GRIS while ensuring repeatability between the observational modes, IFU and long-slit. Results from several tests which have been performed to validate the opto-mechanical prototypes are also presented.

Coupling rotational and translational motion via a continuous measurement in an optomechanical sphere

NASA Astrophysics Data System (ADS)

Ralph, Jason F.; Jacobs, Kurt; Coleman, Jonathon

2016-09-01

We consider a measurement of the position of a spot painted on the surface of a trapped nano-optomechanical sphere. The measurement extracts information about the position of the spot and in doing so measures a combination of the orientation and position of the sphere. The quantum backaction of the measurement entangles and correlates these two degrees of freedom. Such a measurement is not available for atoms or ions and provides a mechanism to probe the quantum mechanical properties of trapped optomechanical spheres. In performing simulations of this measurement process we also test a numerical method introduced recently by Rouchon and collaborators [H. Amini, M. Mirrahimi, and P. Rouchon, in Proceedings of the 50th IEEE Conference on Decision and Control (CDC, 2011), pp. 6242-6247; P. Rouchon and J. F. Ralph, Phys. Rev. A 91, 012118 (2015), 10.1103/PhysRevA.91.012118] for solving stochastic master equations. This method guarantees the positivity of the density matrix when the Lindblad operators for all simultaneous continuous measurements are mutually commuting. We show that it is both simpler and far more efficient than previous methods.

Photonic and phononic surface and edge modes in three-dimensional phoxonic crystals

NASA Astrophysics Data System (ADS)

Ma, Tian-Xue; Wang, Yue-Sheng; Zhang, Chuanzeng

2018-04-01

We investigate the photonic and phononic surface and edge modes in finite-size three-dimensional phoxonic crystals. By appropriately terminating the phoxonic crystals, the photons and phonons can be simultaneously guided at the two-dimensional surface and/or the one-dimensional edge of the terminated crystals. The Bloch surface and edge modes show that the electromagnetic and acoustic waves are highly localized near the surface and edge, respectively. The surface and edge geometries play important roles in tailoring the dispersion relations of the surface and edge modes, and dual band gaps for the surface or edge modes can be simultaneously achieved by changing the geometrical configurations. Furthermore, as the band gaps for the bulk modes are the essential prerequisites for the realization of dual surface and edge modes, the photonic and phononic bulk-mode band gap properties of three different types of phoxonic crystals with six-connected networks are revealed. It is found that the geometrical characteristic of the crystals with six-connected networks leads to dual large bulk-mode band gaps. Compared with the conventional bulk modes, the surface and edge modes provide a new approach for the photon and phonon manipulation and show great potential for phoxonic crystal devices and optomechanics.

Interfacing whispering-gallery microresonators and free space light with cavity enhanced Rayleigh scattering

PubMed Central

Zhu, Jiangang; Özdemir, Şahin K.; Yilmaz, Huzeyfe; Peng, Bo; Dong, Mark; Tomes, Matthew; Carmon, Tal; Yang, Lan

2014-01-01

Whispering gallery mode resonators (WGMRs) take advantage of strong light confinement and long photon lifetime for applications in sensing, optomechanics, microlasers and quantum optics. However, their rotational symmetry and low radiation loss impede energy exchange between WGMs and the surrounding. As a result, free-space coupling of light into and from WGMRs is very challenging. In previous schemes, resonators are intentionally deformed to break circular symmetry to enable free-space coupling of carefully aligned focused light, which comes with bulky size and alignment issues that hinder the realization of compact WGMR applications. Here, we report a new class of nanocouplers based on cavity enhanced Rayleigh scattering from nano-scatterer(s) on resonator surface, and demonstrate whispering gallery microlaser by free-space optical pumping of an Ytterbium doped silica microtoroid via the scatterers. This new scheme will not only expand the range of applications enabled by WGMRs, but also provide a possible route to integrate them into solar powered green photonics. PMID:25227918

Interfacing whispering-gallery microresonators and free space light with cavity enhanced Rayleigh scattering.

PubMed

Zhu, Jiangang; Özdemir, Sahin K; Yilmaz, Huzeyfe; Peng, Bo; Dong, Mark; Tomes, Matthew; Carmon, Tal; Yang, Lan

2014-09-17

Whispering gallery mode resonators (WGMRs) take advantage of strong light confinement and long photon lifetime for applications in sensing, optomechanics, microlasers and quantum optics. However, their rotational symmetry and low radiation loss impede energy exchange between WGMs and the surrounding. As a result, free-space coupling of light into and from WGMRs is very challenging. In previous schemes, resonators are intentionally deformed to break circular symmetry to enable free-space coupling of carefully aligned focused light, which comes with bulky size and alignment issues that hinder the realization of compact WGMR applications. Here, we report a new class of nanocouplers based on cavity enhanced Rayleigh scattering from nano-scatterer(s) on resonator surface, and demonstrate whispering gallery microlaser by free-space optical pumping of an Ytterbium doped silica microtoroid via the scatterers. This new scheme will not only expand the range of applications enabled by WGMRs, but also provide a possible route to integrate them into solar powered green photonics.

Scanning electron microscope view of iron crystal

NASA Technical Reports Server (NTRS)

1972-01-01

A scanning electron microscope photograph of iron crystals which grow in a small vug or cavity in a recrystallized breccia (fragmented rock) from the Apollo 15 Hadley-Apennino lunar landing site. The largest crystal is three microns across. Perfectly developed crystals such as these indicate slow formation from a hot vapor as the rock was cooling. The crystals are resting on an interlocking lattice of pyroxene (calsium-magnesium-iron silicate).

Scanning electron microscope view of iron crystal

NASA Image and Video Library

1972-11-10

A scanning electron microscope photograph of iron crystals which grow in a small vug or cavity in a recrystallized breccia (fragmented rock) from the Apollo 15 Hadley-Apennino lunar landing site. The largest crystal is three microns across. Perfectly developed crystals such as these indicate slow formation from a hot vapor as the rock was cooling. The crystals are resting on an interlocking lattice of pyroxene (calsium-magnesium-iron silicate).

Polymer lattices as mechanically tunable 3-dimensional photonic crystals operating in the infrared

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chernow, V. F., E-mail: vchernow@caltech.edu; Alaeian, H.; Department of Materials Science and Engineering, Stanford University, Stanford, California 94305

2015-09-07

Broadly tunable photonic crystals in the near- to mid-infrared region could find use in spectroscopy, non-invasive medical diagnosis, chemical and biological sensing, and military applications, but so far have not been widely realized. We report the fabrication and characterization of three-dimensional tunable photonic crystals composed of polymer nanolattices with an octahedron unit-cell geometry. These photonic crystals exhibit a strong peak in reflection in the mid-infrared that shifts substantially and reversibly with application of compressive uniaxial strain. A strain of ∼40% results in a 2.2 μm wavelength shift in the pseudo-stop band, from 7.3 μm for the as-fabricated nanolattice to 5.1 μm when strained.more » We found a linear relationship between the overall compressive strain in the photonic crystal and the resulting stopband shift, with a ∼50 nm blueshift in the reflection peak position per percent increase in strain. These results suggest that architected nanolattices can serve as efficient three-dimensional mechanically tunable photonic crystals, providing a foundation for new opto-mechanical components and devices across infrared and possibly visible frequencies.« less

Mechanism of 150-cavity formation in influenza neuraminidase

PubMed Central

Amaro, Rommie E.; Swift, Robert V.; Votapka, Lane; Li, Wilfred W.; Walker, Ross C.; Bush, Robin M.

2011-01-01

The recently discovered 150-cavity in the active site of group-1 influenza A neuraminidase (NA) proteins provides a target for rational structure-based drug development to counter the increasing frequency of antiviral resistance in influenza. Surprisingly, the 2009 H1N1 pandemic virus (09N1) neuramidase was crystalized without the 150-cavity characteristic of group-1 NAs. Here we demonstrate, through a total sum of 1.6 μs of biophysical simulations, that 09N1 NA exists in solution preferentially with an open 150-cavity. Comparison with simulations using avian N1, human N2 and 09N1 with a I149V mutation and an extensive bioinformatics analysis suggests that the conservation of a key salt bridge is crucial in the stabilization of the 150-cavity across both subtypes. This result provides an atomic-level structural understanding of the recent finding that antiviral compounds designed to take advantage of contacts in the 150-cavity can inactivate both 2009 H1N1 pandemic and avian H5N1 viruses. PMID:21750542

Optical spring effect in nanoelectromechanical systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tian, Feng; Zhou, Guangya, E-mail: mpezgy@nus.edu.sg; Du, Yu

2014-08-11

In this Letter, we report a hybrid system consisting of nano-optical and nano-mechanical springs, in which the optical spring effect works to adjust the mechanical frequency of a nanoelectromechanical systems resonator. Nano-scale folded beams are fabricated as the mechanical springs and double-coupled one-dimensional photonic crystal cavities are used to pump the “optical spring.” The dynamic characteristics of this hybrid system are measured and analyzed at both low and high input optical powers. This study leads the physical phenomenon of optomechanics in complex nano-opto-electro-mechanical systems (NOEMS) and could benefit the future applications of NOEMS in chip-level communication and sensing.

Nonlinear dynamics and quantum entanglement in optomechanical systems.

PubMed

Wang, Guanglei; Huang, Liang; Lai, Ying-Cheng; Grebogi, Celso

2014-03-21

To search for and exploit quantum manifestations of classical nonlinear dynamics is one of the most fundamental problems in physics. Using optomechanical systems as a paradigm, we address this problem from the perspective of quantum entanglement. We uncover strong fingerprints in the quantum entanglement of two common types of classical nonlinear dynamical behaviors: periodic oscillations and quasiperiodic motion. There is a transition from the former to the latter as an experimentally adjustable parameter is changed through a critical value. Accompanying this process, except for a small region about the critical value, the degree of quantum entanglement shows a trend of continuous increase. The time evolution of the entanglement measure, e.g., logarithmic negativity, exhibits a strong dependence on the nature of classical nonlinear dynamics, constituting its signature.

Fabrication of elliptical SRF cavities

NASA Astrophysics Data System (ADS)

Singer, W.

2017-03-01

The technological and metallurgical requirements of material for high-gradient superconducting cavities are described. High-purity niobium, as the preferred metal for the fabrication of superconducting accelerating cavities, should meet exact specifications. The content of interstitial impurities such as oxygen, nitrogen, and carbon must be below 10 μg g-1. The hydrogen content should be kept below 2 μg g-1 to prevent degradation of the quality factor (Q-value) under certain cool-down conditions. The material should be free of flaws (foreign material inclusions or cracks and laminations) that can initiate a thermal breakdown. Traditional and alternative cavity mechanical fabrication methods are reviewed. Conventionally, niobium cavities are fabricated from sheet niobium by the formation of half-cells by deep drawing, followed by trim machining and electron beam welding. The welding of half-cells is a delicate procedure, requiring intermediate cleaning steps and a careful choice of weld parameters to achieve full penetration of the joints. A challenge for a welded construction is the tight mechanical and electrical tolerances. These can be maintained by a combination of mechanical and radio-frequency measurements on half-cells and by careful tracking of weld shrinkage. The main aspects of quality assurance and quality management are mentioned. The experiences of 800 cavities produced for the European XFEL are presented. Another cavity fabrication approach is slicing discs from the ingot and producing cavities by deep drawing and electron beam welding. Accelerating gradients at the level of 35-45 MV m-1 can be achieved by applying electrochemical polishing treatment. The single-crystal option (grain boundary free) is discussed. It seems that in this case, high performance can be achieved by a simplified treatment procedure. Fabrication of the elliptical resonators from a seamless pipe as an alternative is briefly described. This technology has yielded good

COMBINE*: An integrated opto-mechanical tool for laser performance modeling

NASA Astrophysics Data System (ADS)

Rehak, M.; Di Nicola, J. M.

2015-02-01

Accurate modeling of thermal, mechanical and optical processes is important for achieving reliable, high-performance high energy lasers such as those at the National Ignition Facility [1] (NIF). The need for this capability is even more critical for high average power, high repetition rate applications. Modeling the effects of stresses and temperature fields on optical properties allows for optimal design of optical components and more generally of the architecture of the laser system itself. Stresses change the indices of refractions and induce inhomogeneities and anisotropy. We present a modern, integrated analysis tool that efficiently produces reliable results that are used in our laser propagation tools such as VBL [5]. COMBINE is built on and supplants the existing legacy tools developed for the previous generations of lasers at LLNL but also uses commercially available mechanical finite element codes ANSYS or COMSOL (including computational fluid dynamics). The COMBINE code computes birefringence and wave front distortions due to mechanical stresses on lenses and slabs of arbitrary geometry. The stresses calculated typically originate from mounting support, vacuum load, gravity, heat absorption and/or attending cooling. Of particular importance are the depolarization and detuning effects of nonlinear crystals due to thermal loading. Results are given in the form of Jones matrices, depolarization maps and wave front distributions. An incremental evaluation of Jones matrices and ray propagation in a 3D mesh with a stress and temperature field is performed. Wavefront and depolarization maps are available at the optical aperture and at slices within the optical element. The suite is validated, user friendly, supported, documented and amenable to collaborative development. * COMBINE stands for Code for Opto-Mechanical Birefringence Integrated Numerical Evaluations.

Lasers with intra-cavity phase elements

NASA Astrophysics Data System (ADS)

Gulses, A. Alkan; Kurtz, Russell; Islas, Gabriel; Anisimov, Igor

2018-02-01

Conventional laser resonators yield multimodal output, especially at high powers and short cavity lengths. Since highorder modes exhibit large divergence, it is desirable to suppress them to improve laser quality. Traditionally, such modal discriminations can be achieved by simple apertures that provide absorptive loss for large diameter modes, while allowing the lower orders, such as the fundamental Gaussian, to pass through. However, modal discrimination may not be sufficient for short-cavity lasers, resulting in multimodal operation as well as power loss and overheating in the absorptive part of the aperture. In research to improve laser mode control with minimal energy loss, systematic experiments have been executed using phase-only elements. These were composed of an intra-cavity step function and a diffractive out-coupler made of a computer-generated hologram. The platform was a 15-cm long solid-state laser that employs a neodymium-doped yttrium orthovanadate crystal rod, producing 1064 nm multimodal laser output. The intra-cavity phase elements (PEs) were shown to be highly effective in obtaining beams with reduced M-squared values and increased output powers, yielding improved values of radiance. The utilization of more sophisticated diffractive elements is promising for more difficult laser systems.

A highly stable monolithic enhancement cavity for second harmonic generation in the ultraviolet

NASA Astrophysics Data System (ADS)

Hannig, S.; Mielke, J.; Fenske, J. A.; Misera, M.; Beev, N.; Ospelkaus, C.; Schmidt, P. O.

2018-01-01

We present a highly stable bow-tie power enhancement cavity for critical second harmonic generation (SHG) into the UV using a Brewster-cut β-BaB2O4 (BBO) nonlinear crystal. The cavity geometry is suitable for all UV wavelengths reachable with BBO and can be modified to accommodate anti-reflection coated crystals, extending its applicability to the entire wavelength range accessible with non-linear frequency conversion. The cavity is length-stabilized using a fast general purpose digital PI controller based on the open source STEMlab 125-14 (formerly Red Pitaya) system acting on a mirror mounted on a fast piezo actuator. We observe 130 h uninterrupted operation without decay in output power at 313 nm. The robustness of the system has been confirmed by exposing it to accelerations of up to 1 g with less than 10% in-lock output power variations. Furthermore, the cavity can withstand 30 min of acceleration exposure at a level of 3 grms without substantial change in the SHG output power, demonstrating that the design is suitable for transportable setups.

Call for Papers: Cavity QED

NASA Astrophysics Data System (ADS)

Lange, W.; Gerard, J.-M.

2003-06-01

Cavity QED interactions of light and matter have been investigated in a wide range of systems covering the spectrum from microwaves to optical frequencies, using media as diverse as single atoms and semiconductors. Impressive progress has been achieved technologically as well as conceptually. This topical issue of Journal of Optics B: Quantum and Semiclassical Optics is intended to provide a comprehensive account of the current state of the art of cavity QED by uniting contributions from researchers active across this field. As Guest Editors of this topical issue, we invite manuscripts on current theoretical and experimental work on any aspects of cavity QED. The topics to be covered will include, but are not limited to: bulletCavity QED in optical microcavities bulletSemiconductor cavity QED bulletQuantum dot cavity QED bulletRydberg atoms in microwave cavities bulletPhotonic crystal cavity QED bulletMicrosphere resonators bulletMicrolasers and micromasers bulletMicrodroplets bulletDielectric cavity QED bulletCavity QED-based quantum information processing bulletQuantum state engineering in cavities The DEADLINE for submission of contributions is 31 July 2003 to allow the topical issue to appear in about February 2004. All papers will be peer-reviewed in accordance with the normal refereeing procedures and standards of Journal of Optics B: Quantum and Semiclassical Optics. Advice on publishing your work in the journal may be found at www.iop.org/journals/authors/jopb. Submissions should ideally be in either standard LaTeX form or Microsoft Word. There are no page charges for publication. In addition to the usual 50 free reprints, the corresponding author of each paper published will receive a complimentary copy of the topical issue. Contributions to the topical issue should if possible be submitted electronically at www.iop.org/journals/jopb. or by e-mail to jopb@iop.org. Authors unable to submit online or by e-mail may send hard copy contributions (enclosing the

Levitated Optomechanics for Fundamental Physics

NASA Astrophysics Data System (ADS)

Rashid, Muddassar; Bateman, James; Vovrosh, Jamie; Hempston, David; Ulbricht, Hendrik

2015-05-01

Optomechanics with levitated nano- and microparticles is believed to form a platform for testing fundamental principles of quantum physics, as well as find applications in sensing. We will report on a new scheme to trap nanoparticles, which is based on a parabolic mirror with a numerical aperture of 1. Combined with achromatic focussing, the setup is a cheap and readily straightforward solution to trapping nanoparticles for further study. Here, we report on the latest progress made in experimentation with levitated nanoparticles; these include the trapping of 100 nm nanodiamonds (with NV-centres) down to 1 mbar as well as the trapping of 50 nm Silica spheres down to 10?4 mbar without any form of feedback cooling. We will also report on the progress to implement feedback stabilisation of the centre of mass motion of the trapped particle using digital electronics. Finally, we argue that such a stabilised particle trap can be the particle source for a nanoparticle matterwave interferometer. We will present our Talbot interferometer scheme, which holds promise to test the quantum superposition principle in the new mass range of 106 amu. EPSRC, John Templeton Foundation.

High-contrast controllable switching based on polystyrene nonlinear cavities in 2D hole-type photonic crystals

NASA Astrophysics Data System (ADS)

Paghousi, Roohollah; Fasihi, Kiazand

2018-05-01

We present a new high-contrast controllable switch, which is based on a polystyrene nonlinear cavity, and is implemented in a two dimensional (2D) hole-type photonic crystal (PC). We show that by applying a control signal, the input power can be transmitted to the output waveguide with a high contrast ratio. The operation of the proposed device is investigated through the use of coupled-mode theory (CMT) and finite-difference time-domain (FDTD) method. The contrast ratio of the proposed device varies between 18 and 23, which is higher than the corresponding value in the previous investigations. Based on the simulation results, with increasing the control power the range of operating power will be increased, while the contrast ratio will be decreased. It has been shown that in a modified structure, at the expense of the range of operating power and the contrast ratio, the control power can be decreased, considerably.

Edge waves and resonances in two-dimensional phononic crystal plates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, Jin-Chen, E-mail: hsujc@yuntech.edu.tw; Hsu, Chih-Hsun

2015-05-07

We present a numerical study on phononic band gaps and resonances occurring at the edge of a semi-infinite two-dimensional (2D) phononic crystal plate. The edge supports localized edge waves coupling to evanescent phononic plate modes that decay exponentially into the semi-infinite phononic crystal plate. The band-gap range and the number of edge-wave eigenmodes can be tailored by tuning the distance between the edge and the semi-infinite 2D phononic lattice. As a result, a phononic band gap for simultaneous edge waves and plate waves is created, and phononic cavities beside the edge can be built to support high-frequency edge resonances. Wemore » design an L3 edge cavity and analyze its resonance characteristics. Based on the band gap, high quality factor and strong confinement of resonant edge modes are achieved. The results enable enhanced control over acoustic energy flow in phononic crystal plates, which can be used in designing micro and nanoscale resonant devices and coupling of edge resonances to other types of phononic or photonic crystal cavities.« less

Optomechanical design and testing of the VLT tertiary mirrors

NASA Astrophysics Data System (ADS)

Bollinger, Wolfgang; Juranek, Hans J.; Schulte, Stefan; May, K.; Michel, Alain

2000-07-01

The Tertiary Mirrors for the ESO Very Large Telescope project consist of four optical flats (elliptical, 890 X 1260 mm2). The achieved opto-mechanical design is challenging since it provides high optical overall quality combined with high stiffness (70 Hz Eigenfrequency) and low mass (total mass of 180 kg for the complete unit). Schott (Mainz, Germany) produces the lightweight Zerodur blanks. Carl Zeiss has designed and manufactured the mirror and its support cell. Last not least it became necessary to install the biggest testing equipment for flats in Europe to guarantee for a scientifically correct verification of the quality of the complete unit. All four mirrors have been delivered to ESO.

High-Q/V Monolithic Diamond Microdisks Fabricated with Quasi-isotropic Etching.

PubMed

Khanaliloo, Behzad; Mitchell, Matthew; Hryciw, Aaron C; Barclay, Paul E

2015-08-12

Optical microcavities enhance light-matter interactions and are essential for many experiments in solid state quantum optics, optomechanics, and nonlinear optics. Single crystal diamond microcavities are particularly sought after for applications involving diamond quantum emitters, such as nitrogen vacancy centers, and for experiments that benefit from diamond's excellent optical and mechanical properties. Light-matter coupling rates in experiments involving microcavities typically scale with Q/V, where Q and V are the microcavity quality-factor and mode-volume, respectively. Here we demonstrate that microdisk whispering gallery mode cavities with high Q/V can be fabricated directly from bulk single crystal diamond. By using a quasi-isotropic oxygen plasma to etch along diamond crystal planes and undercut passivated diamond structures, we create monolithic diamond microdisks. Fiber taper based measurements show that these devices support TE- and TM-like optical modes with Q > 1.1 × 10(5) and V < 11(λ/n) (3) at a wavelength of 1.5 μm.

New optomechanical approach to quantitative characterization of fatigue behavior of dynamically loaded structures

NASA Astrophysics Data System (ADS)

Furlong, Cosme; Pryputniewicz, Ryszard J.

1995-06-01

The basic relationships between stress and strain under cyclic conditions of loading are not at present well understood. It would seem that information of this type is vital for a fundamental approach to understand the fatigue behavior of dynamically loaded structures. In this paper, experimental and computational methods are utilized to study the fatigue behavior of a thin aluminum cantilever plate subjected to dynamic loading. The studies are performed by combining optomechanical and finite element methods. The cantilever plate is loaded periodically by excitation set at a fixed amplitude and at a specific resonance frequency of the plate. By continuously applying this type of loading and using holographic interferometry, the behavior of the plate during a specific period of time is investigated. Quantitative information is obtained from laser vibrometry data which are utilized by a finite element program to calculate strains and stresses assuming a homogeneous and isotropic material and constant strain elements. It is shown that the use of experimental and computational hybrid methodologies allows identification of different zones of the plate that are fatigue critical. This optomechanical approach proves to be a viable tool for understanding of fatigue behavior of mechanical components and for performing optimization of structures subjected to fatigue conditions.

Tunable-Range, Photon-Mediated Atomic Interactions in Multimode Cavity QED

NASA Astrophysics Data System (ADS)

Vaidya, Varun D.; Guo, Yudan; Kroeze, Ronen M.; Ballantine, Kyle E.; Kollár, Alicia J.; Keeling, Jonathan; Lev, Benjamin L.

2018-01-01

Optical cavity QED provides a platform with which to explore quantum many-body physics in driven-dissipative systems. Single-mode cavities provide strong, infinite-range photon-mediated interactions among intracavity atoms. However, these global all-to-all couplings are limiting from the perspective of exploring quantum many-body physics beyond the mean-field approximation. The present work demonstrates that local couplings can be created using multimode cavity QED. This is established through measurements of the threshold of a superradiant, self-organization phase transition versus atomic position. Specifically, we experimentally show that the interference of near-degenerate cavity modes leads to both a strong and tunable-range interaction between Bose-Einstein condensates (BECs) trapped within the cavity. We exploit the symmetry of a confocal cavity to measure the interaction between real BECs and their virtual images without unwanted contributions arising from the merger of real BECs. Atom-atom coupling may be tuned from short range to long range. This capability paves the way toward future explorations of exotic, strongly correlated systems such as quantum liquid crystals and driven-dissipative spin glasses.

Quantum Photonic in Hybrid Cavity Systems with Strong Matter-Light Couplings

DTIC Science & Technology

2015-08-24

properties. [Ref 1, 6] 2. Confinement and coupling of microcavity polaritons were readily implemented by design of the photonic crystal in the new...cavity structure, allowing flexible device design and integration of the polariton system. Zero-dimensional polariton systems were created by reducing...the area of the photonic crystal, coupling between multiple zero-dimensional polariton systems was controlled by design of the boundaries of the

Guided Acoustic and Optical Waves in Silicon-on-Insulator for Brillouin Scattering and Optomechanics

DTIC Science & Technology

2016-08-01

APL PHOTONICS 1, 071301 (2016) Guided acoustic and optical waves in silicon-on- insulator for Brillouin scattering and optomechanics Christopher J...is possible to simultaneously guide optical and acoustic waves in the technologically important silicon on insulator (SOI) material system. Thin...mechanism on which to base on-chip nonlinear optical devices compatible with a rapidly growing silicon photonics toolbox.3–9 While silicon on insulator

Wavelength-scale photonic-crystal laser formed by electron-beam-induced nano-block deposition.

PubMed

Seo, Min-Kyo; Kang, Ju-Hyung; Kim, Myung-Ki; Ahn, Byeong-Hyeon; Kim, Ju-Young; Jeong, Kwang-Yong; Park, Hong-Gyu; Lee, Yong-Hee

2009-04-13

A wavelength-scale cavity is generated by printing a carbonaceous nano-block on a photonic-crystal waveguide. The nanometer-size carbonaceous block is grown at a pre-determined region by the electron-beam-induced deposition method. The wavelength-scale photonic-crystal cavity operates as a single mode laser, near 1550 nm with threshold of approximately 100 microW at room temperature. Finite-difference time-domain computations show that a high-quality-factor cavity mode is defined around the nano-block with resonant wavelength slightly longer than the dispersion-edge of the photonic-crystal waveguide. Measured near-field images exhibit photon distribution well-localized in the proximity of the printed nano-block. Linearly-polarized emission along the vertical direction is also observed.

High density protein crystal growth

NASA Technical Reports Server (NTRS)

Rouleau, Robyn (Inventor); Hedden, Douglas Keith (Inventor); Delucas, Lawrence (Inventor)

2004-01-01

A protein crystal growth assembly including a crystal growth cell and further including a cell body having a top side and a bottom side and a first aperture defined therethrough, the cell body having opposing first and second sides and a second aperture defined therethrough. A cell barrel is disposed within the cell body, the cell barrel defining a cavity alignable with the first aperture of the cell body, the cell barrel being rotatable within the second aperture. A reservoir is coupled to the bottom side of the cell body and a cap having a top side is disposed on the top side of the cell body. The protein crystal growth assembly may be employed in methods including vapor diffusion crystallization, liquid to liquid crystallization, batch crystallization, and temperature induction batch mode crystallization.

Optical circulation in a multimode optomechanical resonator.

PubMed

Ruesink, Freek; Mathew, John P; Miri, Mohammad-Ali; Alù, Andrea; Verhagen, Ewold

2018-05-04

Breaking the symmetry of electromagnetic wave propagation enables important technological functionality. In particular, circulators are nonreciprocal components that can route photons directionally in classical or quantum photonic circuits and offer prospects for fundamental research on electromagnetic transport. Developing highly efficient circulators thus presents an important challenge, especially to realise compact reconfigurable implementations that do not rely on magnetic fields to break reciprocity. We demonstrate optical circulation utilising radiation pressure interactions in an on-chip multimode optomechanical system. Mechanically mediated optical mode conversion in a silica microtoroid provides a synthetic gauge bias for light, enabling four-port circulation that exploits tailored interference between appropriate light paths. We identify two sideband conditions under which ideal circulation is approached. This allows to experimentally demonstrate ~10 dB isolation and <3 dB insertion loss in all relevant channels. We show the possibility of actively controlling the circulator properties, enabling ideal opportunities for reconfigurable integrated nanophotonic circuits.

Interference effects in a cavity for optical amplification

NASA Astrophysics Data System (ADS)

Cardimona, D. A.; Alsing, P. M.

2009-08-01

In space situational awareness scenarios, the objects needed to be characterized and identified are usually quite far away and quite dim. Thus, optical detectors need to be able to sense these very dim optical signals. Quantum interference in a three-level system can lead to amplification of optical signals. If we put a three-level system into a cavity tuned to the frequency of an incoming optical signal, we anticipate the amplification possibilities should be increased proportional to the quality factor of the cavity. Our vision is to utilize quantum dots in photonic crystal cavities, but as a stepping stone we first investigate a simple three-level system in a free-space optical cavity. We investigate quantum interference and classical interference effects when a three-level system interacts with both a cavity field mode and an external driving field mode. We find that under certain circumstances the cavity field evolves to be equal in magnitude to, but 180° out-of-phase with the external pump field when the pump field frequency equals the cavity frequency. At this point the resonance fluorescence from the atom in the cavity goes to zero due to a purely classical interference effect between the two out-of-phase fields. This is quite different from the quantum interference that occurs under the right circumstances, when the state populations are coherently driven into a linear combination that is decoupled from any applied field - and population is trapped in the excited states, thus allowing for a population inversion and an amplification of incoming optical signals.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiong, Hao, E-mail: haoxiong1217@gmail.com; Fan, Yu-Wan; Yang, Xiaoxue

We investigate radiation-pressure induced generation of the frequency components at the difference-sideband in an optomechanical system, which beyond the conventional linearized description of optomechanical interactions between cavity fields and the mechanical oscillation. We analytically calculate amplitudes of these signals, and identify a simple square-root law for both the upper and lower difference-sideband generation which can describe the dependence of the intensities of these signals on the pump power. Further calculation shows that difference-sideband generation can be greatly enhanced via achieving the matching conditions. The effect of difference-sideband generation, which may have potential application for manipulation of light, is especially suitedmore » for on-chip optomechanical devices, where nonlinear optomechanical interaction in the weak coupling regime is within current experimental reach.« less

Dielectric micro-resonator-based opto-mechanical systems for sensing applications

NASA Astrophysics Data System (ADS)

Ali, Amir Roushdy

In recent years, whispering gallery mode (WGM), or morphology dependent optical resonances (MDR) of dielectric micro-resonators have attracted interest with proposed applications in a wide range of areas due to the high optical quality factors, Q, they can exhibit (reaching ~ 10. 9 for silica spheres). Micro-resonator WGMs have been used in applications that include those in spectroscopy, micro-cavity laser technology, optical communications (switching, filtering and multiplexing), sensors technologies and even chemical and biological sensing. The WGM of these dielectric micro-resonators are highly sensitive to morphological changes (such as the size, shape, or refractive index) of the resonance cavity and hence, can be tuned by causing a minute change in the physical condition of the surrounding. In this dissertation, we have been creating opto-mechanical systems, which at their most basic, are extraordinarily sensitive sensors. One of the ultimate goals of this dissertation is to develop sensors capable of detecting the extremely small electric field changes. To improve the performance of the sensors, we couple a polymer cantilever beam to a dielectric micro-resonator. The eventual use of such ultra sensitive electric filed sensors could include neural-machine interfaces for advanced prosthetics devices. The work presented here includes a basic analysis and experimental investigations of the electric field sensitivity and range of micro-resonators of several different materials and geometries followed by the electric field sensor design, testing, and characterization. Also, the effects of angular velocity on the WGM shifts of spherical micro-resonators are also investigated. The elastic deformation that is induced on a spinning resonator due to the centrifugal force may lead to a sufficient shift in the optical resonances and therefore interfering with its desirable operational sensor design. Furthermore, this principle could be used for the development of

Hemispherical cavities on silicon substrates: an overview of micro fabrication techniques

NASA Astrophysics Data System (ADS)

Poncelet, O.; Rasson, J.; Tuyaerts, R.; Coulombier, M.; Kotipalli, R.; Raskin, J.-P.; Francis, L. A.

2018-04-01

Hemispherical photonic crystals found in species like Papilio blumei and Cicendella chinensis have inspired new applications like anti-counterfeiting devices and gas sensors. In this work, we investigate and compare four different ways to micro fabricate such hemispherical cavities: using colloids as template, by wet (HNA) or dry (XeF2) isotropic etching of silicon and by electrochemical etching of silicon. The shape and the roughness of the obtained cavities have been discussed and the pros/cons for each method are highlighted.

Photonic crystal wave guide for non-cryogenic cooled carbon nanotube based middle wave infrared sensors

NASA Astrophysics Data System (ADS)

Fung, Carmen Kar Man; Xi, Ning; Lou, Jianyong; Lai, King Wai Chiu; Chen, Hongzhi

2010-10-01

We report high sensitivity carbon nanotube (CNT) based middle wave infrared (MWIR) sensors with a two-dimensional photonic crystal waveguide. MWIR sensors are of great importance in a variety of current military applications including ballistic missile defense, surveillance and target detection. Unlike other existing MWIR sensing materials, CNTs exhibit low noise level and can be used as new nano sensing materials for MWIR detection where cryogenic cooling is not required. However, the quantum efficiency of the CNT based infrared sensor is still limited by the small sensing area and low incoming electric field. Here, a photonic nanostructure is used as a resonant cavity for boosting the electric field intensity at the position of the CNT sensing element. A two-dimensional photonic crystal with periodic holes in a polymer thin film is fabricated and a resonant cavity is formed by removing holes from the array of the photonic crystal. Based on the design of the photonic crystal topologies, we theoretically study the electric field distribution to predict the resonant behavior of the structure. Numerical simulations reveal the field is enhanced and almost fully confined to the defect region of the photonic crystal. To verify the electric field enhancement effect, experiments are also performed to measure the photocurrent response of the sensor with and without the photonic crystal resonant cavity. Experimental results show that the photocurrent increases ~3 times after adding the photonic crystal resonant cavity.

Opto-mechanical subsystem of a 10 micrometer wavelength receiver terminal. Waveguide laser local oscillator. Servo system

NASA Technical Reports Server (NTRS)

1975-01-01

An engineering model opto-mechanical subsystem for a 10.6-micrometer laser heterodyne receiver is developed, and a CO2 waveguide local oscillator and servo electronics are provided for the receiver. Design goals are presented for the subsystems and overall package design is described. Thermal and mechanical distortion loading tests were performed and the results are included.

Intrinsic cavity QED and emergent quasinormal modes for a single photon

NASA Astrophysics Data System (ADS)

Dong, H.; Gong, Z. R.; Ian, H.; Zhou, Lan; Sun, C. P.

2009-06-01

We propose a special cavity design that is constructed by terminating a one-dimensional waveguide with a perfect mirror at one end and doping a two-level atom at the other. We show that this atom plays the intrinsic role of a semitransparent mirror for single-photon transports such that quasinormal modes emerge spontaneously in the cavity system. This atomic mirror has its reflection coefficient tunable through its level spacing and its coupling to the cavity field, for which the cavity system can be regarded as a two-end resonator with a continuously tunable leakage. The overall investigation predicts the existence of quasibound states in the waveguide continuum. Solid-state implementations based on a dc-superconducting quantum interference device circuit and a defected line resonator embedded in a photonic crystal are illustrated to show the experimental accessibility of the generic model.

Strong exciton-photon coupling in organic single crystal microcavity with high molecular orientation

NASA Astrophysics Data System (ADS)

Goto, Kaname; Yamashita, Kenichi; Yanagi, Hisao; Yamao, Takeshi; Hotta, Shu

2016-08-01

Strong exciton-photon coupling has been observed in a highly oriented organic single crystal microcavity. This microcavity consists of a thiophene/phenylene co-oligomer (TPCO) single crystal laminated on a high-reflection distributed Bragg reflector. In the TPCO crystal, molecular transition dipole was strongly polarized along a certain horizontal directions with respect to the main crystal plane. This dipole polarization causes significantly large anisotropies in the exciton transition and optical constants. Especially the anisotropic exciton transition was found to provide the strong enhancement in the coupling with the cavity mode, which was demonstrated by a Rabi splitting energy as large as ˜100 meV even in the "half-vertical cavity surface emitting lasing" microcavity structure.

Optomechanically-induced transparency in parity-time-symmetric microresonators

PubMed Central

Jing, H.; Özdemir, Şahin K.; Geng, Z.; Zhang, Jing; Lü, Xin-You; Peng, Bo; Yang, Lan; Nori, Franco

2015-01-01

Optomechanically-induced transparency (OMIT) and the associated slowing of light provide the basis for storing photons in nanoscale devices. Here we study OMIT in parity-time (PT)-symmetric microresonators with a tunable gain-to-loss ratio. This system features a sideband-reversed, non-amplifying transparency , i.e., an inverted-OMIT. When the gain-to-loss ratio is varied, the system exhibits a transition from a PT-symmetric phase to a broken-PT-symmetric phase. This PT-phase transition results in the reversal of the pump and gain dependence of the transmission rates. Moreover, we show that by tuning the pump power at a fixed gain-to-loss ratio, or the gain-to-loss ratio at a fixed pump power, one can switch from slow to fast light and vice versa. These findings provide new tools for controlling light propagation using nanofabricated phononic devices. PMID:26169253

Optomechanical terahertz detection with single meta-atom resonator.

PubMed

Belacel, Cherif; Todorov, Yanko; Barbieri, Stefano; Gacemi, Djamal; Favero, Ivan; Sirtori, Carlo

2017-11-17

Most of the common technologies for detecting terahertz photons (>1 THz) at room temperature rely on slow thermal devices. The realization of fast and sensitive detectors in this frequency range is indeed a notoriously difficult task. Here we propose a novel device consisting of a subwavelength terahertz meta-atom resonator, which integrates a nanomechanical element and allows energy exchange between the mechanical motion and the electromagnetic degrees of freedom. An incident terahertz wave thus produces a nanomechanical signal that can be read out optically with high precision. We exploit this concept to demonstrate a terahertz detector that operates at room temperature with high sensitivity and a much higher frequency response compared to standard detectors. Beyond the technological issue of terahertz detection, our architecture opens up new perspectives for fundamental science of light-matter interaction at terahertz frequencies, combining optomechanical approaches with semiconductor quantum heterostructures.

The opto-mechanical design process: from vision to reality

NASA Astrophysics Data System (ADS)

Kvamme, E. Todd; Stubbs, David M.; Jacoby, Michael S.

2017-08-01

The design process for an opto-mechanical sub-system is discussed from requirements development through test. The process begins with a proper mission understanding and the development of requirements for the system. Preliminary design activities are then discussed with iterative analysis and design work being shared between the design, thermal, and structural engineering personnel. Readiness for preliminary review and the path to a final design review are considered. The value of prototyping and risk mitigation testing is examined with a focus on when it makes sense to execute a prototype test program. System level margin is discussed in general terms, and the practice of trading margin in one area of performance to meet another area is reviewed. Requirements verification and validation is briefly considered. Testing and its relationship to requirements verification concludes the design process.

Testing Quantum Gravity Induced Nonlocality via Optomechanical Quantum Oscillators.

PubMed

Belenchia, Alessio; Benincasa, Dionigi M T; Liberati, Stefano; Marin, Francesco; Marino, Francesco; Ortolan, Antonello

2016-04-22

Several quantum gravity scenarios lead to physics below the Planck scale characterized by nonlocal, Lorentz invariant equations of motion. We show that such nonlocal effective field theories lead to a modified Schrödinger evolution in the nonrelativistic limit. In particular, the nonlocal evolution of optomechanical quantum oscillators is characterized by a spontaneous periodic squeezing that cannot be generated by environmental effects. We discuss constraints on the nonlocality obtained by past experiments, and show how future experiments (already under construction) will either see such effects or otherwise cast severe bounds on the nonlocality scale (well beyond the current limits set by the Large Hadron Collider). This paves the way for table top, high precision experiments on massive quantum objects as a promising new avenue for testing some quantum gravity phenomenology.

DNA Brick Crystals with Prescribed Depth

PubMed Central

Ke, Yonggang; Ong, Luvena L.; Sun, Wei; Song, Jie; Dong, Mingdong; Shih, William M.; Yin, Peng

2014-01-01

We describe a general framework for constructing two-dimensional crystals with prescribed depth and sophisticated three-dimensional features. These crystals may serve as scaffolds for the precise spatial arrangements of functional materials for diverse applications. The crystals are self-assembled from single-stranded DNA components called DNA bricks. We demonstrate the experimental construction of DNA brick crystals that can grow to micron-size in the lateral dimensions with precisely controlled depth up to 80 nanometers. They can be designed to display user-specified sophisticated three-dimensional nanoscale features, such as continuous or discontinuous cavities and channels, and to pack DNA helices at parallel and perpendicular angles relative to the plane of the crystals. PMID:25343605

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.

Optomechanical design concept for GMACS: a wide-field multi-object moderate resolution optical spectrograph for the Giant Magellan Telescope (GMT)

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Prochaska, Travis; Shectman, Stephen A.; Hammond, Randolph P.; Barkhouser, Robert H.; DePoy, D. L.; Marshall, J. L.

2012-09-01

We describe the conceptual optomechanical design for GMACS, a wide-field, multi-object, moderate-resolution optical spectrograph for the Giant Magellan Telescope (GMT). GMACS is a candidate first-light instrument for the GMT and will be one of several instruments housed in the Gregorian Instrument Rotator (GIR) located at the Gregorian focus. The instrument samples a 9 arcminute x 18 arcminute field of view providing two resolution modes (i.e, low resolution, R ~ 2000, and moderate resolution, R ~ 4000) over a 3700 Å to 10200 Å wavelength range. To minimize the size of the optics, four fold mirrors at the GMT focal plane redirect the full field into four individual "arms", that each comprises a double spectrograph with a red and blue channel. Hence, each arm samples a 4.5 arcminute x 9 arcminute field of view. The optical layout naturally leads to three separate optomechanical assemblies: a focal plane assembly, and two identical optics modules. The focal plane assembly contains the last element of the telescope's wide-field corrector, slit-mask, tent-mirror assembly, and slit-mask magazine. Each of the two optics modules supports two of the four instrument arms and houses the aft-optics (i.e. collimators, dichroics, gratings, and cameras). A grating exchange mechanism, and articulated gratings and cameras facilitate multiple resolution modes. In this paper we describe the details of the GMACS optomechanical design, including the requirements and considerations leading to the design, mechanism details, optics mounts, and predicted flexure performance.

Dynamic acousto-optic control of a strongly coupled photonic molecule

PubMed Central

Kapfinger, Stephan; Reichert, Thorsten; Lichtmannecker, Stefan; Müller, Kai; Finley, Jonathan J.; Wixforth, Achim; Kaniber, Michael; Krenner, Hubert J.

2015-01-01

Strongly confined photonic modes can couple to quantum emitters and mechanical excitations. To harness the full potential in quantum photonic circuits, interactions between different constituents have to be precisely and dynamically controlled. Here, a prototypical coupled element, a photonic molecule defined in a photonic crystal membrane, is controlled by a radio frequency surface acoustic wave. The sound wave is tailored to deliberately switch on and off the bond of the photonic molecule on sub-nanosecond timescales. In time-resolved experiments, the acousto-optically controllable coupling is directly observed as clear anticrossings between the two nanophotonic modes. The coupling strength is determined directly from the experimental data. Both the time dependence of the tuning and the inter-cavity coupling strength are found to be in excellent agreement with numerical calculations. The demonstrated mechanical technique can be directly applied for dynamic quantum gate operations in state-of-the-art-coupled nanophotonic, quantum cavity electrodynamic and optomechanical systems. PMID:26436203

Nonradiating and radiating modes excited by quantum emitters in open epsilon-near-zero cavities

PubMed Central

Liberal, Iñigo; Engheta, Nader

2016-01-01

Controlling the emission and interaction properties of quantum emitters (QEs) embedded within an optical cavity is a key technique in engineering light-matter interactions at the nanoscale, as well as in the development of quantum information processing. State-of-the-art optical cavities are based on high quality factor photonic crystals and dielectric resonators. However, wealthier responses might be attainable with cavities carved in more exotic materials. We theoretically investigate the emission and interaction properties of QEs embedded in open epsilon-near-zero (ENZ) cavities. Using analytical methods and numerical simulations, we demonstrate that open ENZ cavities present the unique property of supporting nonradiating modes independently of the geometry of the external boundary of the cavity (shape, size, topology, etc.). Moreover, the possibility of switching between radiating and nonradiating modes enables a dynamic control of the emission by, and the interaction between, QEs. These phenomena provide unprecedented degrees of freedom in controlling and trapping fields within optical cavities, as well as in the design of cavity opto- and acoustomechanical systems. PMID:27819047

Nonradiating and radiating modes excited by quantum emitters in open epsilon-near-zero cavities.

PubMed

Liberal, Iñigo; Engheta, Nader

2016-10-01

Controlling the emission and interaction properties of quantum emitters (QEs) embedded within an optical cavity is a key technique in engineering light-matter interactions at the nanoscale, as well as in the development of quantum information processing. State-of-the-art optical cavities are based on high quality factor photonic crystals and dielectric resonators. However, wealthier responses might be attainable with cavities carved in more exotic materials. We theoretically investigate the emission and interaction properties of QEs embedded in open epsilon-near-zero (ENZ) cavities. Using analytical methods and numerical simulations, we demonstrate that open ENZ cavities present the unique property of supporting nonradiating modes independently of the geometry of the external boundary of the cavity (shape, size, topology, etc.). Moreover, the possibility of switching between radiating and nonradiating modes enables a dynamic control of the emission by, and the interaction between, QEs. These phenomena provide unprecedented degrees of freedom in controlling and trapping fields within optical cavities, as well as in the design of cavity opto- and acoustomechanical systems.

Strong exciton-photon coupling in organic single crystal microcavity with high molecular orientation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goto, Kaname; Yamashita, Kenichi, E-mail: yamasita@kit.ac.jp; Yanagi, Hisao

2016-08-08

Strong exciton-photon coupling has been observed in a highly oriented organic single crystal microcavity. This microcavity consists of a thiophene/phenylene co-oligomer (TPCO) single crystal laminated on a high-reflection distributed Bragg reflector. In the TPCO crystal, molecular transition dipole was strongly polarized along a certain horizontal directions with respect to the main crystal plane. This dipole polarization causes significantly large anisotropies in the exciton transition and optical constants. Especially the anisotropic exciton transition was found to provide the strong enhancement in the coupling with the cavity mode, which was demonstrated by a Rabi splitting energy as large as ∼100 meV even inmore » the “half-vertical cavity surface emitting lasing” microcavity structure.« less

Quartz crystal and superconductive resonators and oscillators

NASA Technical Reports Server (NTRS)

Besson, R. S.

1978-01-01

A general overview of piezoelectric resonators is given with emphasis on evolution of the resonator design. Superconducting cavities and crystals at low temperature and the use of resonant frequencies are also discussed.

Dynamic Response of an Optomechanical System to a Stationary Random Excitation in the Time Domain

DOE PAGES

Palmer, Jeremy A.; Paez, Thomas L.

2011-01-01

Modern electro-optical instruments are typically designed with assemblies of optomechanical members that support optics such that alignment is maintained in service environments that include random vibration loads. This paper presents a nonlinear numerical analysis that calculates statistics for the peak lateral response of optics in an optomechanical sub-assembly subject to random excitation of the housing. The work is unique in that the prior art does not address peak response probability distribution for stationary random vibration in the time domain for a common lens-retainer-housing system with Coulomb damping. Analytical results are validated by using displacement response data from random vibration testingmore » of representative prototype sub-assemblies. A comparison of predictions to experimental results yields reasonable agreement. The Type I Asymptotic form provides the cumulative distribution function for peak response probabilities. Probabilities are calculated for actual lens centration tolerances. The probability that peak response will not exceed the centration tolerance is greater than 80% for prototype configurations where the tolerance is high (on the order of 30 micrometers). Conversely, the probability is low for those where the tolerance is less than 20 micrometers. The analysis suggests a design paradigm based on the influence of lateral stiffness on the magnitude of the response.« less

Nanoscale Biosensor Based on Silicon Photonic Cavity for Home Healthcare Diagnostic Application

NASA Astrophysics Data System (ADS)

Ebrahimy, Mehdi N.; Moghaddam, Aydin B.; Andalib, Alireza; Naziri, Mohammad; Ronagh, Nazli

2015-09-01

In this paper, a new ultra-compact optical biosensor based on photonic crystal (phc) resonant cavity is proposed. This sensor has ability to work in chemical optical processes for the determination and analysis of liquid material. Here, we used an optical filter based on two-dimensional phc resonant cavity on a silicon layer and an active area is created in center of cavity. According to results, with increasing the refractive index of cavity, resonant wavelengths shift so that this phenomenon provides the ability to measure the properties of materials. This novel designed biosensor has more advantage to operate in the biochemical process for example sensing protein and DNA molecule refractive index. This nanoscale biosensor has quality factor higher than 1.5 × 104 and it is suitable to be used in the home healthcare diagnostic applications.

Use of stabilizing mutations to engineer a charged group within a ligand-binding hydrophobic cavity in T4 lysozyme.

PubMed

Liu, Lijun; Baase, Walter A; Michael, Miya M; Matthews, Brian W

2009-09-22

Both large-to-small and nonpolar-to-polar mutations in the hydrophobic core of T4 lysozyme cause significant loss in stability. By including supplementary stabilizing mutations we constructed a variant that combines the cavity-creating substitution Leu99 --> Ala with the buried charge mutant Met102 --> Glu. Crystal structure determination confirmed that this variant has a large cavity with the side chain of Glu102 located within the cavity wall. The cavity includes a large disk-shaped region plus a bulge. The disk-like region is essentially nonpolar, similar to L99A, while the Glu102 substituent is located in the vicinity of the bulge. Three ordered water molecules bind within this part of the cavity and appear to stabilize the conformation of Glu102. Glu102 has an estimated pKa of about 5.5-6.5, suggesting that it is at least partially charged in the crystal structure. The polar ligands pyridine, phenol and aniline bind within the cavity, and crystal structures of the complexes show one or two water molecules to be retained. Nonpolar ligands of appropriate shape can also bind in the cavity and in some cases exclude all three water molecules. This disrupts the hydrogen-bond network and causes the Glu102 side chain to move away from the ligand by up to 0.8 A where it remains buried in a completely nonpolar environment. Isothermal titration calorimetry revealed that the binding of these compounds stabilizes the protein by 4-6 kcal/mol. For both polar and nonpolar ligands the binding is enthalpically driven. Large negative changes in entropy adversely balance the binding of the polar ligands, whereas entropy has little effect on the nonpolar ligand binding.

Fabrication of triangular nanobeam waveguide networks in bulk diamond using single-crystal silicon hard masks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayn, I.; Mouradian, S.; Li, L.

2014-11-24

A scalable approach for integrated photonic networks in single-crystal diamond using triangular etching of bulk samples is presented. We describe designs of high quality factor (Q = 2.51 × 10{sup 6}) photonic crystal cavities with low mode volume (V{sub m} = 1.062 × (λ/n){sup 3}), which are connected via waveguides supported by suspension structures with predicted transmission loss of only 0.05 dB. We demonstrate the fabrication of these structures using transferred single-crystal silicon hard masks and angular dry etching, yielding photonic crystal cavities in the visible spectrum with measured quality factors in excess of Q = 3 × 10{sup 3}.

Cavity turnover and equilibrium cavity densities in a cottonwood bottomland

USGS Publications Warehouse

Sedgwick, James A.; Knopf, Fritz L.

1992-01-01

A fundamental factor regulating the numbers of secondary cavity nesting (SCN) birds is the number of extant cavities available for nesting. The number of available cavities may be thought of as being in an approximate equilibrium maintained by a very rough balance between recruitment and loss of cavities. Based on estimates of cavity recruitment and loss, we ascertained equilibrium cavity densities in a mature plains cottonwood (Populus sargentii) bottomland along the South Platte River in northeastern Colorado. Annual cavity recruitment, derived from density estimates of primary cavity nesting (PCN) birds and cavity excavation rates, was estimated to be 71-86 new cavities excavated/100 ha. Of 180 active cavities of 11 species of cavity-nesting birds found in 1985 and 1986, 83 were no longer usable by 1990, giving an average instantaneous rate of cavity loss of r = -0.230. From these values of cavity recruitment and cavity loss, equilibrium cavity density along the South Platte is 238-289 cavities/100 ha. This range of equilibrium cavity density is only slightly above the minimum of 205 cavities/100 ha required by SCN's and suggests that cavity availability may be limiting SCN densities along the South Platte River. We submit that snag management alone does not adequately address SCN habitat needs, and that cavity management, expressed in terms of cavity turnover and cavity densities, may be more useful.

Dimensional effects on the magnetic domains in planar magnetophotonic crystal waveguides

NASA Astrophysics Data System (ADS)

Huang, Xiaoyue

2007-05-01

The application of photonic crystal technology in magneto-optic media can yield significant improvements in polarization rotation efficiency and optical switching capability and an overall reduction in magneto-optic device dimensions. Resonant photonic crystal structures in planar ferrimagnetic film waveguides are of interest because they may lead to the development of on-chip magneto-optical switches and isolators for photonic device integration. In the present work, two different methods for the fabrication of on-chip waveguide magnetophotonic crystals, through electron beam lithography and focused ion beam milling, are discussed and demonstrated. A high precision photonic measurement system was set up for testing and analysis of the waveguide devices. The results obtained show photonic band gaps with resonant transmission in the gap, and enhanced magneto-optic rotation efficiency. The character of waveguide modes therein, birefringence effects, and structural variation effects were studied extensively and are presented in this thesis. Planar magnetization control produced by manipulation of the magnetic shape anisotropy in the photonic crystal micro-cavity was demonstrated in this work. By introducing strip structures into the resonant cavity formed on magnetic garnet films with in-plane anisotropy, a bi-stable magnetic state and an enhanced magnetic field reversal mechanism were demonstrated. This effect was extensively studied through experimental and micromagnetic simulation analysis of the polarization rotation hysteresis. The results discussed herein show that domain closure loops between the strips limit the magnification of the coercivity in the resonant cavity and that these limitations can be overcome by the formation of isolated single-domain magnetic microstrips in the cavity.

Compact Apparatus Grows Protein Crystals

NASA Technical Reports Server (NTRS)

Bugg, Charles E.; Delucas, Lawrence J.; Suddath, Fred L.; Snyder, Robert S.; Herren, Blair J.; Carter, Daniel C.; Yost, Vaughn H.

1989-01-01

Laboratory apparatus provides delicately balanced combination of materials and chemical conditions for growth of protein crystals. Apparatus and technique for growth based on hanging-drop method for crystallization of macromolecules. Includes pair of syringes with ganged plungers. One syringe contains protein solution; other contains precipitating-agent solution. Syringes intrude into cavity lined with porous reservoir material saturated with 1 mL or more of similar precipitating-agent solution. Prior to activation, ends of syringes plugged to prevent transport of water vapor among three solutions.

Effect of Atomic Layer Deposition on the Quality Factor of Silicon Nanobeam Cavities

DTIC Science & Technology

2012-01-25

Additionally, tuning of 2D photonic crystal systems has been shown using atomic layer deposition (ALD) of hafnium oxide [5] and titanium oxide [6] and plasma...μm. This region of the fiber is then carefully positioned across the nanobeam cavity. A tunable narrowband laser source is coupled into one end of the...fiber, and the trans- mitted power is detected at the other end. As the laser source is tuned into resonance with the cavity, some of the power is

Visualizing breathing motion of internal cavities in concert with ligand migration in myoglobin

PubMed Central

Tomita, Ayana; Sato, Tokushi; Ichiyanagi, Kouhei; Nozawa, Shunsuke; Ichikawa, Hirohiko; Chollet, Matthieu; Kawai, Fumihiro; Park, Sam-Yong; Tsuduki, Takayuki; Yamato, Takahisa; Koshihara, Shin-ya; Adachi, Shin-ichi

2009-01-01

Proteins harbor a number of cavities of relatively small volume. Although these packing defects are associated with the thermodynamic instability of the proteins, the cavities also play specific roles in controlling protein functions, e.g., ligand migration and binding. This issue has been extensively studied in a well-known protein, myoglobin (Mb). Mb reversibly binds gas ligands at the heme site buried in the protein matrix and possesses several internal cavities in which ligand molecules can reside. It is still an open question as to how a ligand finds its migration pathways between the internal cavities. Here, we report on the dynamic and sequential structural deformation of internal cavities during the ligand migration process in Mb. Our method, the continuous illumination of native carbonmonoxy Mb crystals with pulsed laser at cryogenic temperatures, has revealed that the migration of the CO molecule into each cavity induces structural changes of the amino acid residues around the cavity, which results in the expansion of the cavity with a breathing motion. The sequential motion of the ligand and the cavity suggests a self-opening mechanism of the ligand migration channel arising by induced fit, which is further supported by computational geometry analysis by the Delaunay tessellation method. This result suggests a crucial role of the breathing motion of internal cavities as a general mechanism of ligand migration in a protein matrix. PMID:19204297

Oscillator-field model of moving mirrors in quantum optomechanics

NASA Astrophysics Data System (ADS)

Galley, Chad R.; Behunin, Ryan O.; Hu, B. L.

2013-04-01

We present a microphysics model for the kinematics and dynamics of optomechanics describing the coupling between an optical field, modeled here by a massless scalar field, and the internal and mechanical degrees of freedom of a movable mirror. Instead of implementing boundary conditions on the field, we introduce an internal degree of freedom and its dynamics to describe the mirror's reflectivity. Depending on parameter values, the internal degrees of freedom of the mirror in this model capture a range of its optical activities, from those exhibiting broadband reflective properties to those reflecting only in a narrow band. After establishing the model we show how appropriate parameter choices lead to other well-known optomechanical models, including those of Barton and Calogeracos [Ann. Phys. (NY)0003-491610.1006/aphy.1995.1021 238, 227 (1995)], Calogeracos and Barton, Ann. Phys. (NY)10.1006/aphy.1995.1022 238, 268 (1995), Law [Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.51.2537 51, 2537 (1995)], and Golestanian and Kardar [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.78.3421 78, 3421 (1997); Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.58.1713 58, 1713 (1998)]. As a simple illustrative application we derive classical radiation pressure cooling from this model. We then connect our microphysics model to the common descriptions of a moving mirror coupled to radiation pressure (e.g., with Nx coupling, where N is the photon number and x is the mirror displacement), making explicit the underlying assumptions made in these phenomenological models. Our model is also applicable to the lesser explored case of small N, which existing models based on sideband approximations [Kimble , Phys. Rev. DPRVDAQ1550-799810.1103/PhysRevD.65.022002 65, 022002 (2001)] have not addressed. Interestingly, we also find that slow-moving mirrors in our model can be described by the ubiquitous Brownian motion model of quantum open systems. The scope of applications of this model ranges

Large Volume, Optical and Opto-Mechanical Metrology Techniques for ISIM on JWST

NASA Technical Reports Server (NTRS)

Hadjimichael, Theo

2015-01-01

The final, flight build of the Integrated Science Instrument Module (ISIM) element of the James Webb Space Telescope is the culmination of years of work across many disciplines and partners. This paper covers the large volume, ambient, optical and opto-mechanical metrology techniques used to verify the mechanical integration of the flight instruments in ISIM, including optical pupil alignment. We present an overview of ISIM's integration and test program, which is in progress, with an emphasis on alignment and optical performance verification. This work is performed at NASA Goddard Space Flight Center, in close collaboration with the European Space Agency, the Canadian Space Agency, and the Mid-Infrared Instrument European Consortium.

Surface polishing of niobium for superconducting radio frequency (SRF) cavity applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Liang

2014-08-01

Niobium cavities are important components in modern particle accelerators based on superconducting radio frequency (SRF) technology. The interior of SRF cavities are cleaned and polished in order to produce high accelerating field and low power dissipation on the cavity wall. Current polishing methods, buffered chemical polishing (BCP) and electro-polishing (EP), have their advantages and limitations. We seek to improve current methods and explore laser polishing (LP) as a greener alternative of chemical methods. The topography and removal rate of BCP at different conditions (duration, temperature, sample orientation, flow rate) was studied with optical microscopy, scanning electron microscopy (SEM), and electronmore » backscatter diffraction (EBSD). Differential etching on different crystal orientations is the main contributor to fine grain niobium BCP topography, with gas evolution playing a secondary role. The surface of single crystal and bi-crystal niobium is smooth even after heavy BCP. The topography of fine grain niobium depends on total removal. The removal rate increases with temperature and surface acid flow rate within the rage of 0~20 °C, with chemical reaction being the possible dominate rate control mechanism. Surface flow helps to regulate temperature and avoid gas accumulation on the surface. The effect of surface flow rate on niobium EP was studied with optical microscopy, atomic force microscopy (AFM), and power spectral density (PSD) analysis. Within the range of 0~3.7 cm/s, no significant difference was found on the removal rate and the macro roughness. Possible improvement on the micro roughness with increased surface flow rate was observed. The effect of fluence and pulse accumulation on niobium topography during LP was studied with optical microscopy, SEM, AFM, and PSD analysis. Polishing on micro scale was achieved within fluence range of 0.57~0.90 J/cm2, with pulse accumulation adjusted accordingly. Larger area treatment was proved

Pushing the Limits of Piezoresistive Effect by Optomechanical Coupling in 3C-SiC/Si Heterostructure.

PubMed

Md Foisal, Abu Riduan; Qamar, Afzaal; Phan, Hoang-Phuong; Dinh, Toan; Tuan, Khoa-Nguyen; Tanner, Philip; Streed, Erik W; Dao, Dzung Viet

2017-11-22

This letter reports a giant opto-piezoresistive effect in p-3C-SiC/p-Si heterostructure under visible-light illumination. The p-3C-SiC/p-Si heterostructure has been fabricated by growing a 390 nm p-type 3C-SiC on a p-type Si substrate using the low pressure chemical vapor deposition (LPCVD) technique. The gauge factor of the heterostructure was found to be 28 under a dark condition; however, it significantly increased to about -455 under illumination of 635 nm wavelength at 3.0 mW/cm 2 . This gauge factor is over 200 times higher than that of commercial metal strain gauge, 16 times higher than that of 3C-SiC thinfilm, and approximately 5 times larger than that of bulk Si. This enhancement of the gauge factor was attributed to the opto-mechanical coupling effect in p-3C-SiC/p-Si heterostructure. The opto-mechanical coupling effect is the amplified effect of the photoconductivity enhancement and strain-induced band structure modification in the p-type Si substrate. These findings enable extremely high sensitive and robust mechanical sensors, as well as optical sensors at low cost, as no complicated nanofabrication process is required.

Achieving High Sensitivity in Cavity Optomechanical Magnetometry

DTIC Science & Technology

2014-03-08

magnetometers, but with microwatts of power consumption, and without the need for cryogenics. This project was to implement magnetometers at both micro- and...state-of-the-art in SQUID magnetometers, but with microwatts of power consumption, and without the need for cryogenics. This project was to implement...microwatts  of   power   and  at  room  temperature.  This  first  year  of  the  project  fabricated  new  magnetometer

Electro-optic harmonic conversion to switch a laser beam out of a cavity

DOEpatents

Haas, Roger A.; Henesian, Mark A.

1987-01-01

The invention is a switch to permit a laser beam to escape a laser cavity through the use of an externally applied electric field across a harmonic conversion crystal. Amplification takes place in the laser cavity, and then the laser beam is switched out by the laser light being harmonically converted with dichroic or polarization sensitive elements present to alter the optical path of the harmonically converted laser light. Modulation of the laser beam can also be accomplished by varying the external electric field.

Cooling and manipulation of nanoparticles in high vacuum

NASA Astrophysics Data System (ADS)

Millen, J.; Kuhn, S.; Patolsky, F.; Kosloff, A.; Arndt, M.

2016-09-01

Optomechanical systems, where the mechanical motion of objects is measured and controlled using light, have a huge range of applications, from the metre-scale mirrors of LIGO which detect gravitational waves, to micron scale superconducting systems that can transduce quantum signals. A fascinating addition to this field are free or levitated optomechanical systems, where the oscillator is not physically tethered. We study a variety of nanoparticles which are launched through vacuum (10-8 mbar) and interact with an optical cavity. The centre of mass motion of a nanoparticle can be cooled by the optical cavity field. It is predicted that the quantum ground state of motion can be reached, leaving the particle free to evolve after release from the light field, thus preparing nanoscale matter for quantum interference experiments.

Dynamic control of the asymmetric Fano resonance in side-coupled Fabry–Pérot and photonic crystal nanobeam cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Tong; Chau, Fook Siong; Zhou, Guangya, E-mail: mpezgy@nus.edu.sg

2015-11-30

Fano resonance is a prevailing interference phenomenon that stems from the intersection between discrete and continuum states in many fields. We theoretically and experimentally characterize the asymmetric Fano lineshape in side-coupled waveguide Fabry–Pérot and photonic crystal nanobeam cavities. The measured quality-factor of the Fano resonance before tuning is 28 100. A nanoelectromechanical systems bidirectional actuator is integrated seamlessly to control the shape of the Fano resonance through in-plane translations in two directions without sacrificing the quality-factor. The peak intensity level of the Fano resonance can be increased by 8.5 dB from 60 nW to 409 nW while the corresponding dip intensity ismore » increased by 12.8 dB from 1 nW to 18 nW. The maximum recorded quality-factor throughout the tuning procedure is up to 32 500. Potential applications of the proposed structure include enhancing the sensitivity of sensing, reconfigurable nanophotonics devices, and on-chip intensity modulator.« less

(DARPA) Optical Radiation Cooling and Heating In Integrated Devices: Circuit cavity optomechanics for cooling and amplification on a silicon chip

DTIC Science & Technology

2015-07-16

0.02(λ/ n )3 modal volumes while preserving optical cavity Q up to5×106 [Fig. 4(f)-(i)]. The mechanical mode is modeled to have fundamental resonance Qm...addition, a 30.64-MHz resonance is observed and identified as one of the wineglass modes (circumferential number n = 4, “square” mode [40]) with a measured...main challenge is that mechanical resonators operating at high frequencies are extremely stiff, having spring constant on the order of 107 N /m. This

Principles for designing proteins with cavities formed by curved β sheets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcos, Enrique; Basanta, Benjamin; Chidyausiku, Tamuka M.

Active sites and ligand-binding cavities in native proteins are often formed by curved β sheets, and the ability to control β-sheet curvature would allow design of binding proteins with cavities customized to specific ligands. Toward this end, we investigated the mechanisms controlling β-sheet curvature by studying the geometry of β sheets in naturally occurring protein structures and folding simulations. The principles emerging from this analysis were used to design, de novo, a series of proteins with curved β sheets topped with α helices. Nuclear magnetic resonance and crystal structures of the designs closely match the computational models, showing that β-sheetmore » curvature can be controlled with atomic-level accuracy. Our approach enables the design of proteins with cavities and provides a route to custom design ligand-binding and catalytic sites.« less

Two mechanisms of disorder-induced localization in photonic-crystal waveguides

NASA Astrophysics Data System (ADS)

García, P. D.; KiršanskÄ--, G.; Javadi, A.; Stobbe, S.; Lodahl, P.

2017-10-01

Unintentional but unavoidable fabrication imperfections in state-of-the-art photonic-crystal waveguides lead to the spontaneous formation of Anderson-localized modes thereby limiting slow-light propagation and its potential applications. On the other hand, disorder-induced cavities offer an approach to cavity-quantum electrodynamics and random lasing at the nanoscale. The key statistical parameter governing the disorder effects is the localization length, which together with the waveguide length determines the statistical transport of light through the waveguide. In a disordered photonic-crystal waveguide, the localization length is highly dispersive, and therefore, by controlling the underlying lattice parameters, it is possible to tune the localization of the mode. In the present work, we study the localization length in a disordered photonic-crystal waveguide using numerical simulations. We demonstrate two different localization regimes in the dispersion diagram where the localization length is linked to the density of states and the photon effective mass, respectively. The two different localization regimes are identified in experiments by recording the photoluminescence from quantum dots embedded in photonic-crystal waveguides.

Enhanced Deformation of Azobenzene-Modified Liquid Crystal Polymers under Dual Wavelength Exposure: A Photophysical Model

NASA Astrophysics Data System (ADS)

Liu, Ling; Onck, Patrick R.

2017-08-01

Azobenzene-embedded liquid crystal polymers can undergo mechanical deformation in response to ultraviolet (UV) light. The natural rodlike trans state azobenzene absorbs UV light and isomerizes to a bentlike cis state, which disturbs the order of the polymer network, leading to an anisotropic deformation. The current consensus is that the magnitude of the photoinduced deformation is related to the statistical building up of molecules in the cis state. However, a recent experimental study [Liu and Broer, Nat. Commun. 6 8334 (2015)., 10.1038/ncomms9334] shows that a drastic (fourfold) increase of the photoinduced deformation can be generated by exposing the samples simultaneously to 365 nm (UV) and 455 nm (visible) light. To elucidate the physical mechanism that drives this increase, we develop a two-light attenuation model and an optomechanical constitutive relation that not only accounts for the statistical accumulation of cis azobenzenes, but also for the dynamic trans-cis-trans oscillatory isomerization process. Our experimentally calibrated model predicts that the optimal single-wavelength exposure is 395 nm light, a pronounced shift towards the visible spectrum. In addition, we identify a range of optimal combinations of two-wavelength lights that generate a favorable response for a given amount of injected energy. Our model provides mechanistic insight into the different (multi)wavelength exposures used in experiments and, at the same time, opens new avenues towards enhanced, multiwavelength optomechanical behavior.

Controlling signal transport in a carbon nanotube opto-transistor

NASA Astrophysics Data System (ADS)

Li, Jinjin; Chu, Yanhui; Zhu, Ka-Di

2016-11-01

With the highly competitive development of communication technologies, modern information manufactures place high importance on the ability to control the transmitted signal using easy miniaturization materials. A controlled and miniaturized optical information device is, therefore, vital for researchers in information and communication fields. Here we propose a controlled signal transport in a doubly clamped carbon nanotube system, where the transmitted signal can be controlled by another pump beam. Pump off results in the transmitted signal off, while pump on results in the transmitted signal on. The more pump, the more amplified output signal transmission. Analogous with traditional cavity optomechanical system, the role of optical cavity is played by a localized exciton in carbon nanotube while the role of the mechanical element is played by the nanotube vibrations, which enables the realization of an opto-transistor based on carbon nanotube. Since the signal amplification and attenuation have been observed in traditional optomechanical system, and the nanotube optomechanical system has been realized in laboratory, the proposed carbon nanotube opto-transistor could be implemented in current experiments and open the door to potential applications in modern optical networks and future quantum networks.

Power management of direct-view LED backlight for liquid crystal display

NASA Astrophysics Data System (ADS)

Lee, Xuan-Hao; Lin, Che-Chu; Chang, Yu-Yu; Chen, He-Xiang; Sun, Ching-Cherng

2013-03-01

In this paper, we present a study of management of power in function of luminous efficacy of white LED as well as the efficiency enhancement of the direct-view backlight with photon recycling. A cavity efficiency as high as 90.7% is demonstrated for a direct-view backlight with photon recycling. In the future, with a 90% backlight cavity, luminous efficacy of 200 lm/W for white LEDs, and a transmission efficiency of 10% for the liquid crystal panel, the required power of LEDs could be only 16 W. Up to 85% energy saving could be achieved in comparison to the power of the current liquid crystal display.

Resonant second harmonic generation in a gallium nitride two-dimensional photonic crystal on silicon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeng, Y.; Roland, I.; Checoury, X.

We demonstrate second harmonic generation in a gallium nitride photonic crystal cavity embedded in a two-dimensional free-standing photonic crystal platform on silicon. The photonic crystal nanocavity is optically pumped with a continuous-wave laser at telecom wavelengths in the transparency window of the nitride material. The harmonic generation is evidenced by the spectral range of the emitted signal, the quadratic power dependence vs. input power, and the spectral dependence of second harmonic signal. The harmonic emission pattern is correlated to the harmonic polarization generated by the second-order nonlinear susceptibilities χ{sub zxx}{sup (2)}, χ{sub zyy}{sup (2)} and the electric fields of the fundamentalmore » cavity mode.« less

Near-infrared gallium nitride two-dimensional photonic crystal platform on silicon

NASA Astrophysics Data System (ADS)

Roland, I.; Zeng, Y.; Han, Z.; Checoury, X.; Blin, C.; El Kurdi, M.; Ghrib, A.; Sauvage, S.; Gayral, B.; Brimont, C.; Guillet, T.; Semond, F.; Boucaud, P.

2014-07-01

We demonstrate a two-dimensional free-standing gallium nitride photonic crystal platform operating around 1550 nm and fabricated on a silicon substrate. Width-modulated waveguide cavities are integrated and exhibit loaded quality factors up to 34 000 at 1575 nm. We show the resonance tunability by varying the ratio of air hole radius to periodicity, and cavity hole displacement. We deduce a ˜7.9 dB/cm linear absorption loss for the suspended nitride structure from the power dependence of the cavity in-plane transmission.

Higher-order vector beams produced by photonic-crystal lasers.

PubMed

Iwahashi, Seita; Kurosaka, Yoshitaka; Sakai, Kyosuke; Kitamura, Kyoko; Takayama, Naoki; Noda, Susumu

2011-06-20

We have successfully generated vector beams with higher-order polarization states using photonic-crystal lasers. We have analyzed and designed lattice structures that provide cavity modes with different symmetries. Fabricated devices based on these lattice structures produced doughnut-shaped vector beams, with symmetries corresponding to the cavity modes. Our study enables the systematic analysis of vector beams, which we expect will lead to applications such as high-resolution microscopy, laser processing, and optical trapping.

Four-Phase Dendritic Model for the Prediction of Macrosegregation, Shrinkage Cavity, and Porosity in a 55-Ton Ingot

NASA Astrophysics Data System (ADS)

Ge, Honghao; Ren, Fengli; Li, Jun; Han, Xiujun; Xia, Mingxu; Li, Jianguo

2017-03-01

A four-phase dendritic model was developed to predict the macrosegregation, shrinkage cavity, and porosity during solidification. In this four-phase dendritic model, some important factors, including dendritic structure for equiaxed crystals, melt convection, crystals sedimentation, nucleation, growth, and shrinkage of solidified phases, were taken into consideration. Furthermore, in this four-phase dendritic model, a modified shrinkage criterion was established to predict shrinkage porosity (microporosity) of a 55-ton industrial Fe-3.3 wt pct C ingot. The predicted macrosegregation pattern and shrinkage cavity shape are in a good agreement with experimental results. The shrinkage cavity has a significant effect on the formation of positive segregation in hot top region, which generally forms during the last stage of ingot casting. The dendritic equiaxed grains also play an important role on the formation of A-segregation. A three-dimensional laminar structure of A-segregation in industrial ingot was, for the first time, predicted by using a 3D case simulation.

Photonic crystal microchip laser

NASA Astrophysics Data System (ADS)

Gailevicius, D.; Koliadenko, V.; Purlys, V.; Peckus, M.; Taranenko, V.; Staliunas, K.

2017-02-01

The microchip lasers, being sources of coherent light, suffer from one serious drawback: low spatial quality of the beam, strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here we propose that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. We experimentally show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M2 reducing it by factor of 2, and thus increase the brightness of radiation by a factor of 4. This comprises a new kind of laser, the "photonic crystal microchip laser", a very compact and efficient light source emitting high spatial high brightness radiation.

Measurement-induced long-distance entanglement of superconducting qubits using optomechanical transducers

NASA Astrophysics Data System (ADS)

Černotík, Ondřej; Hammerer, Klemens

2016-07-01

Although superconducting systems provide a promising platform for quantum computing, their networking poses a challenge because they cannot be interfaced to light, the medium used to send quantum signals through channels at room temperature. We show that mechanical oscillators can mediate such coupling and light can be used to measure the joint state of two distant qubits. The measurement provides information on the total spin of the two qubits such that entangled qubit states can be postselected. Entanglement generation is possible without ground-state cooling of the mechanical oscillators for systems with optomechanical cooperativity moderately larger than unity; in addition, our setup tolerates a substantial transmission loss. The approach is scalable to the generation of multipartite entanglement and represents a crucial step towards quantum networks with superconducting circuits.

PCF-Based Cavity Enhanced Spectroscopic Sensors for Simultaneous Multicomponent Trace Gas Analysis

PubMed Central

Nakaema, Walter M.; Hao, Zuo-Qiang; Rohwetter, Philipp; Wöste, Ludger; Stelmaszczyk, Kamil

2011-01-01

A multiwavelength, multicomponent CRDS gas sensor operating on the basis of a compact photonic crystal fibre supercontinuum light source has been constructed. It features a simple design encompassing one radiation source, one cavity and one detection unit (a spectrograph with a fitted ICCD camera) that are common for all wavelengths. Multicomponent detection capability of the device is demonstrated by simultaneous measurements of the absorption spectra of molecular oxygen (spin-forbidden b-X branch) and water vapor (polyads 4v, 4v + δ) in ambient atmospheric air. Issues related to multimodal cavity excitation, as well as to obtaining the best signal-to-noise ratio are discussed together with methods for their practical resolution based on operating the cavity in a “quasi continuum” mode and setting long camera gate widths, respectively. A comprehensive review of multiwavelength CRDS techniques is also given. PMID:22319372

EDITORIAL: Photonic Crystal Devices

NASA Astrophysics Data System (ADS)

Bhattacharya, Pallab K.

2007-05-01

The engineering of electromagnetic modes at optical frequencies in artificial dielectric structures with periodic and random variation of the refractive index, enabling control of the radiative properties of the materials and photon localization, was first proposed independently by Yablonovitch and John in 1987. It is possible to control the flow of light in the periodic dielectric structures, known as photonic crystals (PC). As light waves scatter within the photonic crystal, destructive interference cancels out light of certain wavelengths, thereby forming a photonic bandgap, similar to the energy bandgap for electron waves in a semiconductor. Photons whose energies lie within the gap cannot propagate through the periodic structure. This property can be used to make a low-loss cavity. If a point defect, such as one or more missing periods, is introduced into the periodic structure a region is obtained within which the otherwise forbidden wavelengths can be locally trapped. This property can be used to realize photonic microcavities. Similarly, a line of defects can serve as a waveguide. While the realization of three-dimensional (3D) photonic crystals received considerable attention initially, planar two-dimensional (2D) structures are currently favoured because of their relative ease of fabrication. 2D photonic crystal structures provide most of the functionality of 3D structures. These attributes have generated worldwide research and development of sub-μm and μm size active and passive photonic devices such as single-mode and non- classical light sources, guided wave devices, resonant cavity detection, and components for optical communication. More recently, photonic crystal guided wave devices are being investigated for application in microfludic and biochemical sensing. Photonic crystal devices have been realized with bulk, quantum well and quantum dot active regions. The Cluster of articles in this issue of Journal of Physics D: Applied Physics provides a

Near-infrared gallium nitride two-dimensional photonic crystal platform on silicon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roland, I.; Zeng, Y.; Han, Z.

We demonstrate a two-dimensional free-standing gallium nitride photonic crystal platform operating around 1550 nm and fabricated on a silicon substrate. Width-modulated waveguide cavities are integrated and exhibit loaded quality factors up to 34 000 at 1575 nm. We show the resonance tunability by varying the ratio of air hole radius to periodicity, and cavity hole displacement. We deduce a ∼7.9 dB/cm linear absorption loss for the suspended nitride structure from the power dependence of the cavity in-plane transmission.

Comparison on different repetition rate locking methods in Er-doped fiber laser

NASA Astrophysics Data System (ADS)

Yang, Kangwen; Zhao, Peng; Luo, Jiang; Huang, Kun; Hao, Qiang; Zeng, Heping

2018-05-01

We demonstrate a systematic comparative research on the all-optical, mechanical and opto-mechanical repetition rate control methods in an Er-doped fiber laser. A piece of Yb-doped fiber, a piezoelectric transducer and an electronic polarization controller are simultaneously added in the laser cavity as different cavity length modulators. By measuring the cavity length tuning ranges, the output power fluctuations, the temporal and frequency repetition rate stability, we show that all-optical method introduces the minimal disturbances under current experimental condition.

Method to simulate and analyse induced stresses for laser crystal packaging technologies.

PubMed

Ribes-Pleguezuelo, Pol; Zhang, Site; Beckert, Erik; Eberhardt, Ramona; Wyrowski, Frank; Tünnermann, Andreas

2017-03-20

A method to simulate induced stresses for a laser crystal packaging technique and the consequent study of birefringent effects inside the laser cavities has been developed. The method has been implemented by thermo-mechanical simulations implemented with ANSYS 17.0. ANSYS results were later imported in VirtualLab Fusion software where input/output beams in terms of wavelengths and polarization were analysed. The study has been built in the context of a low-stress soldering technique implemented for glass or crystal optics packaging's called the solderjet bumping technique. The outcome of the analysis showed almost no difference between the input and output laser beams for the laser cavity constructed with an yttrium aluminum garnet active laser crystal, a second harmonic generator beta-barium borate, and the output laser mirror made of fused silica assembled by the low-stress solderjet bumping technique.

Quantum synchronization in an optomechanical system based on Lyapunov control.

PubMed

Li, Wenlin; Li, Chong; Song, Heshan

2016-06-01

We extend the concepts of quantum complete synchronization and phase synchronization, which were proposed in A. Mari et al., Phys. Rev. Lett. 111, 103605 (2013)PRLTAO0031-900710.1103/PhysRevLett.111.103605, to more widespread quantum generalized synchronization. Generalized synchronization can be considered a necessary condition or a more flexible derivative of complete synchronization, and its criterion and synchronization measure are proposed and analyzed in this paper. As examples, we consider two typical generalized synchronizations in a designed optomechanical system. Unlike the effort to construct a special coupling synchronization system, we purposefully design extra control fields based on Lyapunov control theory. We find that the Lyapunov function can adapt to more flexible control objectives, which is more suitable for generalized synchronization control, and the control fields can be achieved simply with a time-variant voltage. Finally, the existence of quantum entanglement in different generalized synchronizations is also discussed.

Liquid crystal interfaces: Experiments, simulations and biosensors

NASA Astrophysics Data System (ADS)

Popov, Piotr

Interfacial phenomena are ubiquitous and extremely important in various aspects of biological and industrial processes. For example, many liquid crystal applications start by alignment with a surface. The underlying mechanisms of the molecular organization of liquid crystals at an interface are still under intensive study and continue to be important to the display industry in order to develop better and/or new display technology. My dissertation research has been devoted to studying how complex liquid crystals can be guided to organize at an interface, and to using my findings to develop practical applications. Specifically, I have been working on developing biosensors using liquid-crystal/surfactant/lipid/protein interactions as well as the alignment of low-symmetry liquid crystals for potential new display and optomechanical applications. The biotechnology industry needs better ways of sensing biomaterials and identifying various nanoscale events at biological interfaces and in aqueous solutions. Sensors in which the recognition material is a liquid crystal naturally connects the existing knowledge and experience of the display and biotechnology industries together with surface and soft matter sciences. This dissertation thus mainly focuses on the delicate phenomena that happen at liquid interfaces. In the introduction, I start by defining the interface and discuss its structure and the relevant interfacial forces. I then introduce the general characteristics of biosensors and, in particular, describe the design of biosensors that employ liquid crystal/aqueous solution interfaces. I further describe the basic properties of liquid crystal materials that are relevant for liquid crystal-based biosensing applications. In CHAPTER 2, I describe the simulation methods and experimental techniques used in this dissertation. In CHAPTER 3 and CHAPTER 4, I present my computer simulation work. CHAPTER 3 presents insight of how liquid crystal molecules are aligned by

Frequency-agile terahertz-wave parametric oscillator in a ring-cavity configuration.

PubMed

Minamide, Hiroaki; Ikari, Tomofumi; Ito, Hiromasa

2009-12-01

We demonstrate a frequency-agile terahertz wave parametric oscillator (TPO) in a ring-cavity configuration (ring-TPO). The TPO consists of three mirrors and a MgO:LiNbO(3) crystal under noncollinear phase-matching conditions. A novel, fast frequency-tuning method was realized by controlling a mirror of the three-mirror ring cavity. The wide tuning range between 0.93 and 2.7 THz was accomplished. For first demonstration using the ring-TPO, terahertz spectroscopy was performed as the verification of the frequency-agile performance, measuring the transmission spectrum of the monosaccharide glucose. The spectrum was obtained within about 8 s in good comparison to those of Fourier transform infrared spectrometer.

End-pumped continuous-wave intracavity yellow Raman laser at 590 nm with SrWO4 Raman crystal

NASA Astrophysics Data System (ADS)

Yang, F. G.; You, Z. Y.; Zhu, Z. J.; Wang, Y.; Li, J. F.; Tu, C. Y.

2010-01-01

We present an end-pumped continuous-wave intra-cavity yellow Raman laser at 590 nm with a 60 mm long pure crystal SrWO4 and an intra-cavity LiB3O5 frequency doubling crystal. The highest output power of yellow laser at 590 nm was 230 mW and the output power and threshold were found to be correlative with the polarized directions of pure single crystal SrWO4 deeply. Along different directions, the minimum and maximum thresholds of yellow Raman laser at 590 nm were measured to be 2.8 W and 14.3 W with respect to 808 nm LD pump power, respectively.

Large tuning of birefringence in two strip silicon waveguides via optomechanical motion.

PubMed

Ma, Jing; Povinelli, Michelle L

2009-09-28

We present an optomechanical method to tune phase and group birefringence in parallel silicon strip waveguides. We first calculate the deformation of suspended, parallel strip waveguides due to optical forces. We optimize the frequency and polarization of the pump light to obtain a 9 nm deformation for an optical power of 20 mW. Widely tunable phase and group birefringence can be achieved by varying the pump power, with maximum values of 0.026 and 0.13, respectively. The giant phase birefringence allows linear to circular polarization conversion within 30 microm for a pump power of 67 mW. The group birefringence gives a tunable differential group delay of 6fs between orthogonal polarizations. We also evaluate the tuning performance of waveguides with different cross sections.

Measuring the Dispersion in Laser Cavity Mirrors using White-Light Interferometry

DTIC Science & Technology

2008-03-01

mirrors. Two AlGaInP (aluminum gallium indium phosphide ) diode lasers are aligned such that one is polarized vertically while one is polarized...linear crystals, where the index of refraction depends on beam intensity. Short pulses with high peak intensities are well 14 suited to induce the...MEASURING THE DISPERSION OF LASER CAVITY MIRRORS USING WHITE-LIGHT INTERFEROMETRY THESIS Allison S

Non-invasive diagnostic system and its opto-mechanical probe for combining confocal Raman spectroscopy and optical coherence tomography.

PubMed

Klemes, Jan; Kotzianova, Adela; Pokorny, Marek; Mojzes, Peter; Novak, Jindrich; Sukova, Lada; Demuth, Jaroslav; Vesely, Jaroslav; Sasek, Ladislav; Velebny, Vladimir

2017-11-01

Non-invasive optical diagnostic methods allow important information about studied systems to be obtained in a non-destructive way. Complete diagnosis requires information about the chemical composition as well as the morphological structure of a sample. We report on the development of an opto-mechanical probe that combines Raman spectroscopy (RS) and optical coherence tomography (OCT), two methods that provide all the crucial information needed for a non-invasive diagnosis. The aim of this paper is to introduce the technical design, construction and optimization of a dual opto-mechanical probe combining two in-house developed devices for confocal RS and OCT. The unique benefit of the probe is a gradual acquisition of OCT and RS data, which allows to use the acquired OCT images to pinpoint locations of interest for RS measurements. The parameters and the correct functioning of the probe were verified by RS scanning of various samples (silicon wafer and ex vivo tissue) based on their OCT images - lateral as well as depth scanning was performed. Both the OCT and RS systems were developed, optimized and tested with the ultimate aim of verifying the functionality of the probe. Picture: Schematic illustration and visualization of the developed RS-OCT probe. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photonic Crystal Microchip Laser.

PubMed

Gailevicius, Darius; Koliadenko, Volodymyr; Purlys, Vytautas; Peckus, Martynas; Taranenko, Victor; Staliunas, Kestutis

2016-09-29

The microchip lasers, being very compact and efficient sources of coherent light, suffer from one serious drawback: low spatial quality of the beam strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here it is proposed that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. Experiments show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M 2 reducing it by a factor of 2, and increase the brightness of radiation by a factor of 3. This comprises a new kind of laser, the "photonic crystal microchip laser", a very compact and efficient light source emitting high spatial quality high brightness radiation.

Photonic Crystal Microchip Laser

NASA Astrophysics Data System (ADS)

Gailevicius, Darius; Koliadenko, Volodymyr; Purlys, Vytautas; Peckus, Martynas; Taranenko, Victor; Staliunas, Kestutis

2016-09-01

The microchip lasers, being very compact and efficient sources of coherent light, suffer from one serious drawback: low spatial quality of the beam strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here it is proposed that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. Experiments show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M2 reducing it by a factor of 2, and increase the brightness of radiation by a factor of 3. This comprises a new kind of laser, the “photonic crystal microchip laser”, a very compact and efficient light source emitting high spatial quality high brightness radiation.

Photonic Crystal Microchip Laser

PubMed Central

Gailevicius, Darius; Koliadenko, Volodymyr; Purlys, Vytautas; Peckus, Martynas; Taranenko, Victor; Staliunas, Kestutis

2016-01-01

The microchip lasers, being very compact and efficient sources of coherent light, suffer from one serious drawback: low spatial quality of the beam strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here it is proposed that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. Experiments show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M2 reducing it by a factor of 2, and increase the brightness of radiation by a factor of 3. This comprises a new kind of laser, the “photonic crystal microchip laser”, a very compact and efficient light source emitting high spatial quality high brightness radiation. PMID:27683066

Characterization of etch pits found on a large-grain bulk niobium superconducting radio-frequency resonant cavity

DOE PAGES

Zhao, Xin; Ciovati, G.; Bieler, T. R.

2010-12-15

The performance of superconducting radio-frequency (SRF) resonant cavities made of bulk niobium is limited by nonlinear localized effects. Surface analysis of regions of higher power dissipation is thus of intense interest. Such areas (referred to as “hotspots”) were identified in a large-grain single-cell cavity that had been buffered-chemical polished and dissected for examination by high resolution electron microscopy, electron backscattered diffraction microscopy (EBSD), and optical microscopy. Pits with clearly discernible crystal facets were observed in both “hotspot” and “coldspot” specimens. The pits were found in-grain, at bicrystal boundaries, and on tricrystal junctions. They are interpreted as etch pits induced bymore » crystal defects (e.g. dislocations). All coldspots examined had a qualitatively lower density of etch pits or relatively smooth tricrystal boundary junctions. EBSD mapping revealed the crystal orientation surrounding the pits. Locations with high pit density are correlated with higher mean values of the local average misorientation angle distributions, indicating a higher geometrically necessary dislocation content. In addition, a survey of the samples by energy dispersive x-ray analysis did not show any significant contamination of the samples’ surface. In conclusion, the local magnetic field enhancement produced by the sharp-edge features observed on the samples is not sufficient to explain the observed degradation of the cavity quality factor, which starts at peak surface magnetic field as low as 20 mT.« less

Crystal growth mechanisms in miarolitic cavities in the Lake George ring complex and vicinity, Colorado

USGS Publications Warehouse

Kile, D.E.; Eberl, D.D.

1999-01-01

The Crystal Peak area of the Pikes Peak batholith, near Lake George in central Colorado, is world-renowned for its crystals of amazonite (the blue-green variety of microcline) and smoky quartz. Such crystals, collected from individual miarolitic pegmatites, have a remakably small variation in crystal size within each pegmatite, and the shapes of plots of their crystal size distributions (CSDs) are invariably lognormal or close to lognormal in all cases. These observations are explained by a crystal growth mechanism that was governed initially by surface-controlled kinetics, during which crystals tended to grow larger in proportion to their size, thereby establishing lognormal CSDs. Surface-controlled growth was followed by longer periods of supply controlled growth, during which growth rate was predominantly size-independent, consequently preserving the lognormal shapes of the CSDs and the small size variation. The change from surface- to supply controlled growth kinetics may have resulted from an increasing demand for nutrients that exceeded diffusion limitations of the system. The proposed model for crystal growth in this locality appears to be common in the geologic record, and can be used with other information, such as isotopic data, to deduce physico-chemical conditions during crystal formation.

Recent advances and progress in photonic crystal-based gas sensors

NASA Astrophysics Data System (ADS)

Goyal, Amit Kumar; Sankar Dutta, Hemant; Pal, Suchandan

2017-05-01

This review covers the recent progress made in the photonic crystal-based sensing technology for gas sensing applications. Photonic crystal-based sensing has tremendous potential because of its obvious advantages in sensitivity, stability, miniaturisation, portability, online use, remote monitoring etc. Several 1D and 2D photonic crystal structures including photonic crystal waveguides and cavities for gas sensing applications have been discussed in this review. For each kind of photonic crystal structure, the novelty, measurement principle and their respective gas sensing properties are presented. The reported works and the corresponding results predict the possibility to realize a commercially viable miniaturized and highly sensitive photonic crystal-based optical gas sensor having flexibility in the structure of ultra-compact size with excellent sensing properties.

Microwave Induced Direct Bonding of Single Crystal Silicon Wafers

NASA Technical Reports Server (NTRS)

Budraa, N. K.; Jackson, H. W.; Barmatz, M.

1999-01-01

We have heated polished doped single-crystal silicon wafers in a single mode microwave cavity to temperatures where surface to surface bonding occurred. The absorption of microwaves and heating of the wafers is attributed to the inclusion of n-type or p-type impurities into these substrates. A cylindrical cavity TM (sub 010) standing wave mode was used to irradiate samples of various geometry's at positions of high magnetic field. This process was conducted in vacuum to exclude plasma effects. This initial study suggests that the inclusion of impurities in single crystal silicon significantly improved its microwave absorption (loss factor) to a point where heating silicon wafers directly can be accomplished in minimal time. Bonding of these substrates, however, occurs only at points of intimate surface to surface contact. The inclusion of a thin metallic layer on the surfaces enhances the bonding process.

Enhanced Deformation of Azobenzene-Modified Liquid Crystal Polymers under Dual Wavelength Exposure: A Photophysical Model.

PubMed

Liu, Ling; Onck, Patrick R

2017-08-04

Azobenzene-embedded liquid crystal polymers can undergo mechanical deformation in response to ultraviolet (UV) light. The natural rodlike trans state azobenzene absorbs UV light and isomerizes to a bentlike cis state, which disturbs the order of the polymer network, leading to an anisotropic deformation. The current consensus is that the magnitude of the photoinduced deformation is related to the statistical building up of molecules in the cis state. However, a recent experimental study [Liu and Broer, Nat. Commun. 6 8334 (2015).NCAOBW2041-172310.1038/ncomms9334] shows that a drastic (fourfold) increase of the photoinduced deformation can be generated by exposing the samples simultaneously to 365 nm (UV) and 455 nm (visible) light. To elucidate the physical mechanism that drives this increase, we develop a two-light attenuation model and an optomechanical constitutive relation that not only accounts for the statistical accumulation of cis azobenzenes, but also for the dynamic trans-cis-trans oscillatory isomerization process. Our experimentally calibrated model predicts that the optimal single-wavelength exposure is 395 nm light, a pronounced shift towards the visible spectrum. In addition, we identify a range of optimal combinations of two-wavelength lights that generate a favorable response for a given amount of injected energy. Our model provides mechanistic insight into the different (multi)wavelength exposures used in experiments and, at the same time, opens new avenues towards enhanced, multiwavelength optomechanical behavior.

Efficient 525 nm laser generation in single or double resonant cavity

NASA Astrophysics Data System (ADS)

Liu, Shilong; Han, Zhenhai; Liu, Shikai; Li, Yinhai; Zhou, Zhiyuan; Shi, Baosen

2018-03-01

This paper reports the results of a study into highly efficient sum frequency generation from 792 and 1556 nm wavelength light to 525 nm wavelength light using either a single or double resonant ring cavity based on a periodically poled potassium titanyl phosphate crystal (PPKTP). By optimizing the cavity's parameters, the maximum power achieved for the resultant 525 nm laser was 263 and 373 mW for the single and double resonant cavity, respectively. The corresponding quantum conversion efficiencies were 8 and 77% for converting 1556 nm photons to 525 nm photons with the single and double resonant cavity, respectively. The measured intra-cavity single pass conversion efficiency for both configurations was about 5%. The performances of the sum frequency generation in these two configurations was studied and compared in detail. This work will provide guidelines for optimizing the generation of sum frequency generated laser light for a variety of configurations. The high conversion efficiency achieved in this work will help pave the way for frequency up-conversion of non-classical quantum states, such as the squeezed vacuum and single photon states. The proposed green laser source will be used in our future experiments, which includes a plan to generate two-color entangled photon pairs and achieve the frequency down-conversion of single photons carrying orbital angular momentum.

Three-dimensional computation of laser cavity eigenmodes by the use of finite element analysis (FEA)

NASA Astrophysics Data System (ADS)

Altmann, Konrad; Pflaum, Christoph; Seider, David

2004-06-01

A new method for computing eigenmodes of a laser resonator by the use of finite element analysis (FEA) is presented. For this purpose, the scalar wave equation [Δ + k2]E(x,y,z) = 0 is transformed into a solvable 3D eigenvalue problem by separating out the propagation factor exp(-ikz) from the phasor amplitude E(x,y,z) of the time-harmonic electrical field. For standing wave resonators, the beam inside the cavity is represented by a two-wave ansatz. For cavities with parabolic optical elements the new approach has successfully been verified by the use of the Gaussian mode algorithm. For a DPSSL with a thermally lensing crystal inside the cavity the expected deviation between Gaussian approximation and numerical solution could be demonstrated clearly.

Linewidth Narrowing and Purcell Enhancement in Photonic Crystal Cavities on an Er-Doped Silicon Nitride Platform

DTIC Science & Technology

2010-02-01

Low noise superconducting single photon detectors on silicon,” Appl. Phys. Lett. 93, 131101 (2008). 20. M. T. Tanner, C. M. Natarajan, V. K... wavelength sensitivity in NbTiN superconducting nanowire single-photon detectors fabricated on oxidized silicon substrates,” Proceedings of Single...cavity resonance wavelength and Q-factor for the PC cavity are shown in Figure 3. The data are taken both at low (0.050 mW) pump power and high (30 mW