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Sample records for transistor amplifiers

  1. STABILIZED TRANSISTOR AMPLIFIER

    DOEpatents

    Noe, J.B.

    1963-05-01

    A temperature stabilized transistor amplifier having a pair of transistors coupled in cascade relation that are capable of providing amplification through a temperature range of - 100 un. Concent 85% F to 400 un. Concent 85% F described. The stabilization of the amplifier is attained by coupling a feedback signal taken from the emitter of second transistor at a junction between two serially arranged biasing resistances in the circuit of the emitter of the second transistor to the base of the first transistor. Thus, a change in the emitter current of the second transistor is automatically corrected by the feedback adjustment of the base-emitter potential of the first transistor and by a corresponding change in the base-emitter potential of the second transistor. (AEC)

  2. REGENERATIVE TRANSISTOR AMPLIFIER

    DOEpatents

    Kabell, L.J.

    1958-11-25

    Electrical circults for use in computers and the like are described. particularly a regenerative bistable transistor amplifler which is iurned on by a clock signal when an information signal permits and is turned off by the clock signal. The amplifier porforms the above function with reduced power requirements for the clock signal and circuit operation. The power requirements are reduced in one way by employing transformer coupling which increases the collector circuit efficiency by eliminating the loss of power in the collector load resistor.

  3. Field-effect transistor improves electrometer amplifier

    NASA Technical Reports Server (NTRS)

    Munoz, R.

    1964-01-01

    An electrometer amplifier uses a field effect transistor to measure currents of low amperage. The circuit, developed as an ac amplifier, is used with an external filter which limits bandwidth to achieve optimum noise performance.

  4. Field effect transistors improve buffer amplifier

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Unity gain buffer amplifier with a Field Effect Transistor /FET/ differential input stage responds much faster than bipolar transistors when operated at low current levels. The circuit uses a dual FET in a unity gain buffer amplifier having extremely high input impedance, low bias current requirements, and wide bandwidth.

  5. Characterization of a Common-Source Amplifier Using Ferroelectric Transistors

    NASA Technical Reports Server (NTRS)

    Hunt, Mitchell; Sayyah, Rana; MacLeond, Todd C.; Ho, Pat D.

    2010-01-01

    This paper presents empirical data that was collected through experiments using a FeFET in the established common-source amplifier circuit. The unique behavior of the FeFET lends itself to interesting and useful operation in this widely used common-source amplifier. The paper examines the effect of using a ferroelectric transistor for the amplifier. It also examines the effects of varying load resistance, biasing, and input voltages on the output signal and gives several examples of the output of the amplifier for a given input. The difference between a commonsource amplifier using a ferroelectric transistor and that using a MOSFET is addressed.

  6. InP Heterojunction Bipolar Transistor Amplifiers to 255 GHz

    NASA Technical Reports Server (NTRS)

    Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, William; Dang, Linh; Li, Danny; Cavus, Abdullah; To, Richard; Lai, Richard

    2009-01-01

    Two single-stage InP heterojunction bipolar transistor (HBT) amplifiers operate at 184 and 255 GHz, using Northrop Grumman Corporation s InP HBT MMIC (monolithic microwave integrated circuit) technology. At the time of this reporting, these are reported to be the highest HBT amplifiers ever created. The purpose of the amplifier design is to evaluate the technology capability for high-frequency designs and verify the model for future development work.

  7. Characterization of a Common-Gate Amplifier Using Ferroelectric Transistors

    NASA Technical Reports Server (NTRS)

    Hunt, Mitchell; Sayyah, Rana; MacLeod, Todd C.; Ho, Fat D.

    2011-01-01

    In this paper, the empirical data collected through experiments performed using a FeFET in the common-gate amplifier circuit is presented. The FeFET common-gate amplifier was characterized by varying all parameters in the circuit, such as load resistance, biasing of the transistor, and input voltages. Due to the polarization of the ferroelectric layer, the particular behavior of the FeFET common-gate amplifier presents interesting results. Furthermore, the differences between a FeFET common-gate amplifier and a MOSFET common-gate amplifier are examined.

  8. Ferroelectric Field-Effect Transistor Differential Amplifier Circuit Analysis

    NASA Technical Reports Server (NTRS)

    Phillips, Thomas A.; MacLeod, Todd C.; Ho, Fat D.

    2008-01-01

    There has been considerable research investigating the Ferroelectric Field-Effect Transistor (FeFET) in memory circuits. However, very little research has been performed in applying the FeFET to analog circuits. This paper investigates the use of FeFETs in a common analog circuit, the differential amplifier. The two input Metal-Oxide-Semiconductor (MOS) transistors in a general MOS differential amplifier circuit are replaced with FeFETs. Resistors are used in place of the other three MOS transistors. The FeFET model used in the analysis has been previously reported and was based on experimental device data. Because of the FeFET hysteresis, the FeFET differential amplifier has four different operating modes depending on whether the FeFETs are positively or negatively polarized. The FeFET differential amplifier operation in the different modes was analyzed by calculating the amplifier voltage transfer and gain characteristics shown in figures 2 through 5. Comparisons were made between the FeFET differential amplifier and the standard MOS differential amplifier. Possible applications and benefits of the FeFET differential amplifier are discussed.

  9. Transistor biased amplifier minimizes diode discriminator threshold attenuation

    NASA Technical Reports Server (NTRS)

    Larsen, R. N.

    1967-01-01

    Transistor biased amplifier has a biased diode discriminator driven by a high impedance /several megohms/ current source, rather than a voltage source with several hundred ohms output impedance. This high impedance input arrangement makes the incremental impedance of the threshold diode negligible relative to the input impedance.

  10. E-Learning System for Design and Construction of Amplifier Using Transistors

    ERIC Educational Resources Information Center

    Takemura, Atsushi

    2014-01-01

    This paper proposes a novel e-Learning system for the comprehensive understanding of electronic circuits with transistors. The proposed e-Learning system allows users to learn a wide range of topics, encompassing circuit theories, design, construction, and measurement. Given the fact that the amplifiers with transistors are an integral part of…

  11. VDMOS transistors for power amplifier in UHF band

    NASA Astrophysics Data System (ADS)

    Kassmi, Kamal

    Modeling of power VDMOSFET transistors working in the UHF band is considered. VDMOSFET power structures suited to mobile radiotelephony power amplification are described. A nonlinear physical model suitable for all working regimes is developed. The elements of this model only depend on physical and technological data and bias voltages of the device. A reduced model compatible with SPICE (Simulation Program with Integrated Circuit Emphasis) is presented. A first comparison between measured and computed characteristics is presented under DC switching and small signal conditions. A methodology for the study and design of radio frequency power amplifiers in a nonlinear regime is described. The performance of these devices in terms of power gain, output power, efficiency, linearity and the drain bias influence as well as third order Intermodulation Distortion (IMD3) are considered. It is shown that IMD and power gain performances are controlled by DC output characteristics in the ohmic zone. Practical conclusions with respect to the intrinsic qualities and drawbacks of these products for UHF power amplification are drawn.

  12. Modeling a Common-Source Amplifier Using a Ferroelectric Transistor

    NASA Technical Reports Server (NTRS)

    Sayyah, Rana; Hunt, Mitchell; MacLeond, Todd C.; Ho, Fat D.

    2010-01-01

    This paper presents a mathematical model characterizing the behavior of a common-source amplifier using a FeFET. The model is based on empirical data and incorporates several variables that affect the output, including frequency, load resistance, and gate-to-source voltage. Since the common-source amplifier is the most widely used amplifier in MOS technology, understanding and modeling the behavior of the FeFET-based common-source amplifier will help in the integration of FeFETs into many circuits.

  13. Cryogenic, low-noise high electron mobility transistor amplifiers for the Deep Space Network

    NASA Technical Reports Server (NTRS)

    Bautista, J. J.

    1993-01-01

    The rapid advances recently achieved by cryogenically cooled high electron mobility transistor (HEMT) low-noise amplifiers (LNA's) in the 1- to 10-GHz range are making them extremely competitive with maser amplifiers. In order to address future spacecraft navigation, telemetry, radar, and radio science needs, the Deep Space Network is investing both maser and HEMT amplifiers for its Ka-band (32-GHz) downlink capability. This article describes the current state cryogenic HEMT LNA development at Ka-band for the DSN. Noise performance results at S-band (2.3 GHz) and X-band (8.5 GHz) for HEMT's and masers are included for completeness.

  14. Residual phase noise modeling of amplifiers using silicon bipolar transistors.

    PubMed

    Theodoropoulos, Konstantinos; Everard, Jeremy

    2010-03-01

    In this paper, we describe the modeling of residual 1/f phase noise for Si bipolar amplifiers operating in the linear region. We propose that for Si bipolar amplifiers, the 1/f phase noise is largely caused by the base emitter recombination flicker noise. The up-conversion mechanism is described through linear approximation of the phase variation of the amplifier phase response by the variation of the device parameters (C(b)c, C(be), g(m), r(e)) caused by the recombination 1/f noise. The amplifier phase response describes the device over the whole frequency range of operation for which the influence of the poles and zeros is investigated. It is found that for a common emitter amplifier it is sufficient to only incorporate the effect of the device poles to describe the phase noise behavior over most of its operational frequency range. Simulations predict the measurements of others, including the flattening of the PM noise at frequencies beyond f(3dB), not predicted by previous models.

  15. Field Effect Transistor /FET/ circuit for variable gin amplifiers

    NASA Technical Reports Server (NTRS)

    Spaid, G. H.

    1969-01-01

    Amplifier circuit using two FETs combines improved input and output impedances with relatively large signal handling capability and an immunity from adverse effects of automatic gain control. Circuit has sources and drains in parallel plus a resistive divider for signal and bias to either of the gate terminals.

  16. A Short Study on the Validity of Miller's Theorem Applied to Transistor Amplifier High-Frequency Performance

    ERIC Educational Resources Information Center

    Schubert, T. F., Jr.; Kim, E. M.

    2009-01-01

    The use of Miller's Theorem in the determination of the high-frequency cutoff frequency of transistor amplifiers was recently challenged by a paper published in this TRANSACTIONS. Unfortunately, that paper provided no simulation or experimental results to bring credence to the challenge or to validate the alternate method of determination…

  17. Single shot spin readout with a cryogenic high-electron-mobility transistor amplifier at sub-Kelvin temperatures

    DOE PAGES

    Tracy, Lisa A.; Luhman, Dwight R.; Carr, Stephen M.; Bishop, Nathaniel C.; Ten Eyck, Gregory A.; Pluym, Tammy; Wendt, Joel R.; Lilly, Michael P.; Carroll, Malcolm S.

    2016-02-08

    We use a cryogenic high-electron-mobility transistor circuit to amplify the current from a single electron transistor, allowing for demonstration of single shot readout of an electron spin on a single P donor in Si with 100 kHz bandwidth and a signal to noise ratio of ~9. In order to reduce the impact of cable capacitance, the amplifier is located adjacent to the Si sample, at the mixing chamber stage of a dilution refrigerator. For a current gain of ~2.7 x 103 the power dissipation of the amplifier is 13 μW, the bandwidth is ~1.3 MHz, and for frequencies above 300more » kHz the current noise referred to input is ≤ 70 fA/√Hz. Furthermore, with this amplification scheme, we are able to observe coherent oscillations of a P donor electron spin in isotopically enriched 28Si with 96% visibility.« less

  18. Graphene Distributed Amplifiers: Generating Desirable Gain for Graphene Field-Effect Transistors

    PubMed Central

    Lyu, Hongming; Lu, Qi; Huang, Yilin; Ma, Teng; Zhang, Jinyu; Wu, Xiaoming; Yu, Zhiping; Ren, Wencai; Cheng, Hui-Ming; Wu, Huaqiang; Qian, He

    2015-01-01

    Ever since its discovery, graphene bears great expectations in high frequency electronics due to its irreplaceably high carrier mobility. However, it has long been blamed for the weakness in generating gains, which seriously limits its pace of development. Distributed amplification, on the other hand, has successfully been used in conventional semiconductors to increase the amplifiers’ gain-bandwidth product. In this paper, distributed amplification is first applied to graphene. Transmission lines phase-synchronize paralleled graphene field-effect transistors (GFETs), combining the gain of each stage in an additive manner. Simulations were based on fabricated GFETs whose fT ranged from 8.5 GHz to 10.5 GHz and fmax from 12 GHz to 14 GHz. A simulated four-stage graphene distributed amplifier achieved up to 4 dB gain and 3.5 GHz bandwidth, which could be realized with future IC processes. A PCB level graphene distributed amplifier was fabricated as a proof of circuit concept. PMID:26634442

  19. C-band superconductor/semiconductor hybrid field-effect transistor amplifier on a LaAlO3 substrate

    NASA Technical Reports Server (NTRS)

    Nahra, J. J.; Bhasin, K. B.; Toncich, S. S.; Subramanyam, G.; Kapoor, V. J.

    1992-01-01

    A single-stage C-band superconductor/semiconductor hybrid field-effect transistor amplifier was designed, fabricated, and tested at 77 K. The large area (1 inch x 0.5 inches) high temperature superconducting Tl-Ba-Ca-Cu-O (TBCCO) thin film was rf magnetron sputtered onto a LaAlO3 substrate. The film had a transition temperature of about 92 K after it was patterned and etched. The amplifier showed a gain of 6 dB and a 3 dB bandwidth of 100 MHz centered at 7.9 GHz. An identical gold amplifier circuit was tested at 77 K, and these results are compared with those from the hybrid amplifier.

  20. Design of an Auto-zeroed, Differential, Organic Thin-film Field-effect Transistor Amplifier for Sensor Applications

    NASA Technical Reports Server (NTRS)

    Binkley, David M.; Verma, Nikhil; Crawford, Robert L.; Brandon, Erik; Jackson, Thomas N.

    2004-01-01

    Organic strain gauge and other sensors require high-gain, precision dc amplification to process their low-level output signals. Ideally, amplifiers would be fabricated using organic thin-film field-effect transistors (OTFT's) adjacent to the sensors. However, OTFT amplifiers exhibit low gain and high input-referred dc offsets that must be effectively managed. This paper presents a four-stage, cascaded differential OTFT amplifier utilizing switched capacitor auto-zeroing. Each stage provides a nominal voltage gain of four through a differential pair driving low-impedance active loads, which provide common-mode output voltage control. p-type pentacence OTFT's are used for the amplifier devices and auto-zero switches. Simulations indicate the amplifier provides a nominal voltage gain of 280 V/V and effectively amplifies a 1-mV dc signal in the presence of 500-mV amplifier input-referred dc offset voltages. Future work could include the addition of digital gain calibration and offset correction of residual offsets associated with charge injection imbalance in the differential circuits.

  1. A self-amplified transistor immunosensor under dual gate operation: highly sensitive detection of hepatitis B surface antigen

    NASA Astrophysics Data System (ADS)

    Lee, I.-K.; Jeun, M.; Jang, H.-J.; Cho, W.-J.; Lee, K. H.

    2015-10-01

    Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor based on a self-amplified transistor under dual gate operation (immuno-DG ISFET) for the detection of hepatitis B surface antigen. To address the challenges in current ISFET-based immunosensors, we have enhanced the sensitivity of an immunosensor by precisely tailoring the nanostructure of the transistor. In the pH sensing test, the immuno-DG ISFET showed superior sensitivity (2085.53 mV per pH) to both standard ISFET under single gate operation (58.88 mV per pH) and DG ISFET with a non-tailored transistor (381.14 mV per pH). Moreover, concerning the detection of hepatitis B surface antigens (HBsAg) using the immuno-DG ISFET, we have successfully detected trace amounts of HBsAg (22.5 fg mL-1) in a non-diluted 1× PBS medium with a high sensitivity of 690 mV. Our results demonstrate that the proposed immuno-DG ISFET can be a biosensor platform for practical use in the diagnosis of various diseases.Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor

  2. A self-amplified transistor immunosensor under dual gate operation: highly sensitive detection of hepatitis B surface antigen.

    PubMed

    Lee, I-K; Jeun, M; Jang, H-J; Cho, W-J; Lee, K H

    2015-10-28

    Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor based on a self-amplified transistor under dual gate operation (immuno-DG ISFET) for the detection of hepatitis B surface antigen. To address the challenges in current ISFET-based immunosensors, we have enhanced the sensitivity of an immunosensor by precisely tailoring the nanostructure of the transistor. In the pH sensing test, the immuno-DG ISFET showed superior sensitivity (2085.53 mV per pH) to both standard ISFET under single gate operation (58.88 mV per pH) and DG ISFET with a non-tailored transistor (381.14 mV per pH). Moreover, concerning the detection of hepatitis B surface antigens (HBsAg) using the immuno-DG ISFET, we have successfully detected trace amounts of HBsAg (22.5 fg mL(-1)) in a non-diluted 1× PBS medium with a high sensitivity of 690 mV. Our results demonstrate that the proposed immuno-DG ISFET can be a biosensor platform for practical use in the diagnosis of various diseases.

  3. A Mathematical Model of a Simple Amplifier Using a Ferroelectric Transistor

    NASA Technical Reports Server (NTRS)

    Sayyah, Rana; Hunt, Mitchell; MacLeod, Todd C.; Ho, Fat D.

    2009-01-01

    This paper presents a mathematical model characterizing the behavior of a simple amplifier using a FeFET. The model is based on empirical data and incorporates several variables that affect the output, including frequency, load resistance, and gate-to-source voltage. Since the amplifier is the basis of many circuit configurations, a mathematical model that describes the behavior of a FeFET-based amplifier will help in the integration of FeFETs into many other circuits.

  4. RF Single Electron Transistor Readout Amplifiers for Superconducting Astronomical Detectors for X-Ray to Sub-mm Wavelengths

    NASA Technical Reports Server (NTRS)

    Stevenson, Thomas; Aassime, Abdelhanin; Delsing, Per; Frunzio, Luigi; Li, Li-Qun; Prober, Daniel; Schoelkopf, Robert; Segall, Ken; Wilson, Chris; Stahle, Carl

    2000-01-01

    We report progress on using a new type of amplifier, the Radio-Frequency Single-Electron Transistor (RF-SET), to develop multi-channel sensor readout systems for fast and sensitive readout of high impedance cryogenic photodetectors such as Superconducting Tunnel Junctions and Single Quasiparticle Photon Counters. Although cryogenic, these detectors are desirable because of capabilities not other-wise attainable. However, high impedances and low output levels make low-noise, high-speed readouts challenging, and large format arrays would be facilitated by compact, low-power, on-chip integrated amplifiers. Well-suited for this application are RF-SETs, very high performance electrometers which use an rf readout technique to provide 100 MHz bandwidth. Small size, low power, and cryogenic operation allow direct integration with detectors, and using multiple rf carrier frequencies permits simultaneous readout of 20-50 amplifiers with a common electrical connection. We describe both the first 2-channel demonstration of this wavelength division multiplexing technique for RF-SETs, and Charge-Locked-Loop operation with 100 kHz of closed-loop bandwidth.

  5. High-flux ionic diodes, ionic transistors and ionic amplifiers based on external ion concentration polarization by an ion exchange membrane: a new scalable ionic circuit platform.

    PubMed

    Sun, Gongchen; Senapati, Satyajyoti; Chang, Hsueh-Chia

    2016-04-01

    A microfluidic ion exchange membrane hybrid chip is fabricated using polymer-based, lithography-free methods to achieve ionic diode, transistor and amplifier functionalities with the same four-terminal design. The high ionic flux (>100 μA) feature of the chip can enable a scalable integrated ionic circuit platform for micro-total-analytical systems.

  6. High-flux ionic diodes, ionic transistors and ionic amplifiers based on external ion concentration polarization by an ion exchange membrane: a new scalable ionic circuit platform.

    PubMed

    Sun, Gongchen; Senapati, Satyajyoti; Chang, Hsueh-Chia

    2016-04-01

    A microfluidic ion exchange membrane hybrid chip is fabricated using polymer-based, lithography-free methods to achieve ionic diode, transistor and amplifier functionalities with the same four-terminal design. The high ionic flux (>100 μA) feature of the chip can enable a scalable integrated ionic circuit platform for micro-total-analytical systems. PMID:26960551

  7. Mathematical Models of the Common-Source and Common-Gate Amplifiers using a Metal-Ferroelectric-Semiconductor Field effect Transistor

    NASA Technical Reports Server (NTRS)

    Hunt, Mitchell; Sayyah, Rana; Mitchell, Cody; Laws, Crystal; MacLeod, Todd C.; Ho, Fat D.

    2013-01-01

    Mathematical models of the common-source and common-gate amplifiers using metal-ferroelectric- semiconductor field effect transistors (MOSFETs) are developed in this paper. The models are compared against data collected with MOSFETs of varying channel lengths and widths, and circuit parameters such as biasing conditions are varied as well. Considerations are made for the capacitance formed by the ferroelectric layer present between the gate and substrate of the transistors. Comparisons between the modeled and measured data are presented in depth as well as differences and advantages as compared to the performance of each circuit using a MOSFET.

  8. Extended Characterization of the Common-Source and Common-Gate Amplifiers using a Metal-Ferroelectric-Semiconductor Field Effect Transistor

    NASA Technical Reports Server (NTRS)

    Hunt, Mitchell; Sayyah, Rana; Mitchell, Cody; Laws, Crystal; MacLeod, Todd C.; Ho, Fat D.

    2013-01-01

    Collected data for both common-source and common-gate amplifiers is presented in this paper. Characterizations of the two amplifier circuits using metal-ferroelectric-semiconductor field effect transistors (MFSFETs) are developed with wider input frequency ranges and varying device sizes compared to earlier characterizations. The effects of the ferroelectric layer's capacitance and variation load, quiescent point, or input signal on each circuit are discussed. Comparisons between the MFSFET and MOSFET circuit operation and performance are discussed at length as well as applications and advantages for the MFSFETs.

  9. Amplifier Distortion

    NASA Astrophysics Data System (ADS)

    Keeports, David

    2006-12-01

    By definition, a high fidelity amplifier's instantaneous output voltage is directly proportional to its instantaneous input voltage. While high fidelity is generally valued in the amplification of recorded music, nonlinearity, also known as distortion, is desirable in the amplification of some musical instruments. In particular, guitar amplifiers exploit nonlinearity to increase both the harmonic content and sustain of a guitar's sound. I will discuss how both modifications in sound result from saturation of triode tubes and transistors. Additionally, I will describe the difference in the symmetry of saturation curves for transistors and tubes and the reason why tube guitar amplifiers are generally considered to be superior to solid-state amplifiers. Finally, I will discuss attempts to use solid-state electronics to replicate the sound of tube amplifiers.

  10. DIRECT COUPLED AMPLIFIER

    DOEpatents

    Dandl, R.A.

    1961-09-19

    A transistor amplifier is designed for vyery small currents below 10/sup -8/ amperes. The filrst and second amplifier stages use unusual selected transistors in which the current amplification increases markedly for values of base current below 10/sup -6/ amperes.

  11. A G-band terahertz monolithic integrated amplifier in 0.5-μm InP double heterojunction bipolar transistor technology

    NASA Astrophysics Data System (ADS)

    Ou-Peng, Li; Yong, Zhang; Rui-Min, Xu; Wei, Cheng; Yuan, Wang; Bing, Niu; Hai-Yan, Lu

    2016-05-01

    Design and characterization of a G-band (140-220 GHz) terahertz monolithic integrated circuit (TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm InGaAs/InP double heterojunction bipolar transistor (DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the InP substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140-190 GHz respectively. The saturation output powers are -2.688 dBm at 210 GHz and -2.88 dBm at 220 GHz, respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications. Project supported by the National Natural Science Foundation of China (Grant No. 61501091) and the Fundamental Research Funds for the Central Universities of Ministry of Education of China (Grant Nos. ZYGX2014J003 and ZYGX2013J020).

  12. Amplified Emission and Field-Effect Transistor Characteristics of One-Dimensionally Structured 2,5-Bis(4-biphenylyl)thiophene Crystals.

    PubMed

    Hashimoto, Kazumasa; Sasaki, Fumio; Hotta, Shu; Yanagi, Hisao

    2016-04-01

    One-dimensional (1D) structures of 2,5-bis(4-biphenylyl)thiophene (BP1T) crystals are fabricated for light amplification and field-effect transistor (FET) measurements. A strip-shaped 1D structure (10 µm width) made by photolitography of a vapor-deposited polycrystalline film shows amplified spontaneous emission and lasing oscillations under optical pumping. An FET fabricated with this 1D structure exhibits hole-conduction with a mobility of µh = 8.0 x 10(-3) cm2/Vs. Another 1 D-structured FET is fabricated with epitaxially grown needle-like crystals of BP1T. This needle-crystal FET exhibits higher mobility of µh = 0.34 cm2/Vs. This improved hole mobility is attributed to the single-crystal channel of epitaxial needles while the grain boudaries in the polycrystalline 1 D-structure decrease the carrier transport. PMID:27451604

  13. Amplified spontaneous emission of phonons as a likely mechanism for density-dependent velocity saturation in GaN transistors

    NASA Astrophysics Data System (ADS)

    Khurgin, Jacob B.; Bajaj, Sanyam; Rajan, Siddharth

    2016-09-01

    We show that density-dependent velocity saturation in a GaN high electron mobility transistor (HEMT) can be related to the stimulated emission of longitudinal optical (LO) phonons. As the drift velocity of electrons increases, the drift of the Fermi distribution in reciprocal space results in population inversion and gain for the LO phonons. Once this gain reaches a threshold value, the avalanche-like increase in LO phonon emission causes a rapid loss of electron energy and momentum and leads to drift velocity saturation. Our simple model correctly predicts both the general trend of decreasing saturation velocity with increasing electron density, and the measured experimental values of saturation.

  14. High Power SiGe X-Band (8-10 GHz) Heterojunction Bipolar Transistors and Amplifiers

    NASA Technical Reports Server (NTRS)

    Ma, Zhenqiang; Jiang, Ningyue; Ponchak, George E.; Alterovitz, Samuel A.

    2005-01-01

    Limited by increased parasitics and thermal effects as the device size becomes large, current commercial SiGe power HBTs are difficult to operate at X-band (8-12 GHz) with adequate power added efficiencies at high power levels. We found that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, which thus permits these devices to be efficiently operated at X-band. In this paper, we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8-10 GHz. At 10 GHz, 22.5 dBm (178 mW) RF output power with concurrent gain of 7.32 dB is measured at the peak power-added efficiency of 20.0% and the maximum RF output power of 24.0 dBm (250 mW) is achieved from a 20 emitter finger SiGe power HBT. Demonstration of single-stage X-band medium-power linear MMIC power amplifier is also realized at 8 GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7 dB, a maximum output power of 23.4 dBm and peak power added efficiency of 16% is achieved from the power amplifier. The MMIC exhibits very low distortion with third order intermodulation (IM) suppression C/I of -13 dBc at output power of 21.2 dBm and over 20dBm third order output intercept point (OIP3).

  15. Amplify Interest in STS.

    ERIC Educational Resources Information Center

    Chiappetta, Eugene L; Mays, John D.

    1992-01-01

    Presents activities in which students construct simple crystal radio sets and amplifiers out of diodes, transistors, and integrated circuits. Provides conceptual background, materials needed, instructions, diagrams, and classroom applications. (MDH)

  16. Gyrator employing field effect transistors

    NASA Technical Reports Server (NTRS)

    Hochmair, E. S. (Inventor)

    1973-01-01

    A gyrator circuit of the conventional configuration of two amplifiers in a circular loop, one producing zero phase shift and the other producing 180 deg phase reversal is examined. All active elements are MOS field effect transistors. Each amplifier comprises a differential amplifier configuration with current limiting transistor, followed by an output transistor in cascode configuration, and two load transistors of opposite conductivity type from the other transistors. A voltage divider control circuit comprises a series string of transistors with a central voltage input to provide control, with locations on the amplifiers receiving reference voltages by connection to appropriate points on the divider. The circuit produces excellent response and is well suited for fabrication by integrated circuits.

  17. Cross-differential amplifier

    NASA Technical Reports Server (NTRS)

    Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

    2008-01-01

    A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

  18. Cross-differential amplifier

    NASA Technical Reports Server (NTRS)

    Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

    2011-01-01

    A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

  19. Cross-differential amplifier

    NASA Technical Reports Server (NTRS)

    Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

    2010-01-01

    A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

  20. Cross-differential amplifier

    NASA Technical Reports Server (NTRS)

    Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

    2013-01-01

    A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

  1. Hybrid thin-film amplifier

    NASA Technical Reports Server (NTRS)

    Cleveland, G.

    1977-01-01

    Miniature amplifier for bioelectronic instrumentation consumes only about 100 mW and has frequency response flat to within 0.5 dB from 0.14 to 450 Hz. Device consists of five thin film substrates, which contain eight operational amplifiers and seven field-effect transistor dice.

  2. John Bardeen and transistor physics

    NASA Astrophysics Data System (ADS)

    Huff, Howard R.

    2001-01-01

    John Bardeen and Walter Brattain invented the point-contact semiconductor amplifier (transistor action) in polycrystalline germanium (also observed in polycrystalline silicon) on Dec. 15, 1947, for which they received a patent on Oct. 3, 1950. Bill Shockley was not a co-patent holder on Bardeen and Brattain's point-contact semiconductor amplifier patent since Julius Lilienfeld had already received a patent in 1930 for what would have been Shockley's contribution; namely, the field-effect methodology. Shockley received patents for both his minority-carrier injection concept and junction transistor theory, however, and deservedly shared the Nobel prize with Bardeen and Brattain for his seminal contributions of injection, p-n junction theory and junction transistor theory. We will review the events leading up to the invention of Bardeen and Brattain's point-contact semiconductor amplifier during the magic month of November 17-December 16, 1947 and the invention of Shockley's junction semiconductor amplifier during his magic month of December 24, 1947-January 23, 1948. It was during the course of Bardeen and Brattain's research in November, 1947 that Bardeen also patented the essence of the MOS transistor, wherein the induced minority carriers were confined to the inversion layer enroute to the collector. C. T. Sah has described this device as a sourceless MOS transistor. Indeed, John Bardeen, co-inventor of the point-contact semiconductor amplifier and inventor of the MOS transistor, may rightly be called the father of modern electronics.

  3. High temperature current mirror amplifier

    DOEpatents

    Patterson, III, Raymond B.

    1984-05-22

    A high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is provided with a biasing means and current means on the input leg.

  4. Quantum Thermal Transistor.

    PubMed

    Joulain, Karl; Drevillon, Jérémie; Ezzahri, Younès; Ordonez-Miranda, Jose

    2016-05-20

    We demonstrate that a thermal transistor can be made up with a quantum system of three interacting subsystems, coupled to a thermal reservoir each. This thermal transistor is analogous to an electronic bipolar one with the ability to control the thermal currents at the collector and at the emitter with the imposed thermal current at the base. This is achieved by determining the heat fluxes by means of the strong-coupling formalism. For the case of three interacting spins, in which one of them is coupled to the other two, that are not directly coupled, it is shown that high amplification can be obtained in a wide range of energy parameters and temperatures. The proposed quantum transistor could, in principle, be used to develop devices such as a thermal modulator and a thermal amplifier in nanosystems.

  5. Quantum Thermal Transistor.

    PubMed

    Joulain, Karl; Drevillon, Jérémie; Ezzahri, Younès; Ordonez-Miranda, Jose

    2016-05-20

    We demonstrate that a thermal transistor can be made up with a quantum system of three interacting subsystems, coupled to a thermal reservoir each. This thermal transistor is analogous to an electronic bipolar one with the ability to control the thermal currents at the collector and at the emitter with the imposed thermal current at the base. This is achieved by determining the heat fluxes by means of the strong-coupling formalism. For the case of three interacting spins, in which one of them is coupled to the other two, that are not directly coupled, it is shown that high amplification can be obtained in a wide range of energy parameters and temperatures. The proposed quantum transistor could, in principle, be used to develop devices such as a thermal modulator and a thermal amplifier in nanosystems. PMID:27258859

  6. PULSE AMPLIFIER

    DOEpatents

    Johnstone, C.W.

    1958-06-17

    The improvement of pulse amplifiers used with scintillation detectors is described. The pulse amplifier circuit has the advantage of reducing the harmful effects of overloading cause by large signal inputs. In general the pulse amplifier circuit comprises two amplifier tubes with the input pulses applied to one amplifier grid and coupled to the second amplifier tube through a common cathode load. The output of the second amplifier is coupled from the plate circuit to a cathode follower tube grid and a diode tube in connected from grid to cathode of the cathode follower tube. Degenerative feedback is provided in the second amplifier by coupling a signal from the cathode follower cathode to the second amplifier grid. The circuit proqides moderate gain stability, and overload protection for subsequent pulse circuits.

  7. Ion bipolar junction transistors

    PubMed Central

    Tybrandt, Klas; Larsson, Karin C.; Richter-Dahlfors, Agneta; Berggren, Magnus

    2010-01-01

    Dynamic control of chemical microenvironments is essential for continued development in numerous fields of life sciences. Such control could be achieved with active chemical circuits for delivery of ions and biomolecules. As the basis for such circuitry, we report a solid-state ion bipolar junction transistor (IBJT) based on conducting polymers and thin films of anion- and cation-selective membranes. The IBJT is the ionic analogue to the conventional semiconductor BJT and is manufactured using standard microfabrication techniques. Transistor characteristics along with a model describing the principle of operation, in which an anionic base current amplifies a cationic collector current, are presented. By employing the IBJT as a bioelectronic circuit element for delivery of the neurotransmitter acetylcholine, its efficacy in modulating neuronal cell signaling is demonstrated. PMID:20479274

  8. High temperature current mirror amplifier

    DOEpatents

    Patterson, R.B. III.

    1984-05-22

    Disclosed is a high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is provided with a biasing means and current means on the input leg. 2 figs.

  9. Transistor Effect in Improperly Connected Transistors.

    ERIC Educational Resources Information Center

    Luzader, Stephen; Sanchez-Velasco, Eduardo

    1996-01-01

    Discusses the differences between the standard representation and a realistic representation of a transistor. Presents an experiment that helps clarify the explanation of the transistor effect and shows why transistors should be connected properly. (JRH)

  10. Matched wideband low-noise amplifiers for radio astronomy.

    PubMed

    Weinreb, S; Bardin, J; Mani, H; Jones, G

    2009-04-01

    Two packaged low noise amplifiers for the 0.3-4 GHz frequency range are described. The amplifiers can be operated at temperatures of 300-4 K and achieve noise temperatures in the 5 K range (<0.1 dB noise figure) at 15 K physical temperature. One amplifier utilizes commercially available, plastic-packaged SiGe transistors for first and second stages; the second amplifier is identical except it utilizes an experimental chip transistor as the first stage. Both amplifiers use resistive feedback to provide input reflection coefficient S11<-10 dB over a decade bandwidth with gain over 30 dB. The amplifiers can be used as rf amplifiers in very low noise radio astronomy systems or as i.f. amplifiers following superconducting mixers operating in the millimeter and submillimeter frequency range.

  11. LOGARITHMIC AMPLIFIER

    DOEpatents

    De Shong, J.A. Jr.

    1957-12-31

    A logarithmic current amplifier circuit having a high sensitivity and fast response is described. The inventor discovered the time constant of the input circuit of a system utilizing a feedback amplifier, ionization chamber, and a diode, is inversely proportional to the input current, and that the amplifier becomes unstable in amplifying signals in the upper frequency range when the amplifier's forward gain time constant equals the input circuit time constant. The described device incorporates impedance networks having low frequency response characteristic at various points in the circuit to change the forward gain of the amplifler at a rate of 0.7 of the gain magnitude for every two times increased in frequency. As a result of this improvement, the time constant of the input circuit is greatly reduced at high frequencies, and the amplifier response is increased.

  12. Transferred substrate heterojunction bipolar transistors for submillimeter wave applications

    NASA Technical Reports Server (NTRS)

    Fung, A.; Samoska, L.; Siegel, P.; Rodwell, M.; Urteaga, M.; Paidi, V.

    2003-01-01

    We present ongoing work towards the development of submillimeter wave transistors with goals of realizing advanced high frequency amplifiers, voltage controlled oscillators, active multipliers, and traditional high-speed digital circuits.

  13. High-Speed, high-power, switching transistor

    NASA Technical Reports Server (NTRS)

    Carnahan, D.; Ohu, C. K.; Hower, P. L.

    1979-01-01

    Silicon transistor rate for 200 angstroms at 400 to 600 volts combines switching speed of transistors with ruggedness, power capacity of thyristor. Transistor introduces unique combination of increased power-handling capability, unusally low saturation and switching losses, and submicrosecond switching speeds. Potential applications include high power switching regulators, linear amplifiers, chopper controls for high frequency electrical vehicle drives, VLF transmitters, RF induction heaters, kitchen cooking ranges, and electronic scalpels for medical surgery.

  14. Development and Experimental Evaluation of an Automated Multi-Media Course on Transistors.

    ERIC Educational Resources Information Center

    Whitted, J.H., Jr.; And Others

    A completely automated multi-media self-study program for teaching a portion of electronic solid-state fundamentals was developed. The subject matter areas included were fundamental theory of transistors, transistor amplifier fundamentals, and simple mathematical analysis of transistors including equivalent circuits, parameters, and characteristic…

  15. Operational Amplifiers.

    ERIC Educational Resources Information Center

    Foxcroft, G. E.

    1986-01-01

    Addresses the introduction of low cost equipment into high school and college physical science classes. Examines the properties of an "ideal" operational amplifier and discusses how it might be used under saturated and non-saturated conditions. Notes the action of a "real" operational amplifier. (TW)

  16. Efficient Power Amplifier for Motor Control

    NASA Technical Reports Server (NTRS)

    Brown, R. J.

    1986-01-01

    Pulse-width-modulated amplifier supplies high current as efficiently as low current needed for starting and running motor. Key to efficiency of motor-control amplifier is V-channel metal-oxide/semiconductor transistor Q1. Device has low saturation resistance. However, has large gate input capacitance and small margin between its turn-on voltage and maximum allowable gate-to-source voltage. Circuits for output stages overcome limitations of VMOS device.

  17. Switching Transistor

    NASA Astrophysics Data System (ADS)

    1981-01-01

    Westinghouse Electric Corporation's D60T transistors are used primarily as switching devices for controlling high power in electrical circuits. It enables reduction in the number and size of circuit components and promotes more efficient use of energy. Wide range of application from a popcorn popper to a radio frequency generator for solar cell production.

  18. MMIC DHBT Common-Base Amplifier for 172 GHz

    NASA Technical Reports Server (NTRS)

    Paidi, Vamsi; Griffith, Zack; Wei, Yun; Dahlstrom, Mttias; Urteaga, Miguel; Rodwell, Mark; Samoska, Lorene; Fung, King Man; Schlecht, Erich

    2006-01-01

    Figure 1 shows a single-stage monolithic microwave integrated circuit (MMIC) power amplifier in which the gain element is a double-heterojunction bipolar transistor (DHBT) connected in common-base configuration. This amplifier, which has been demonstrated to function well at a frequency of 172 GHz, is part of a continuing effort to develop compact, efficient amplifiers for scientific instrumentation, wide-band communication systems, and radar systems that will operate at frequencies up to and beyond 180 GHz. The transistor is fabricated from a layered structure formed by molecular beam epitaxy in the InP/InGaAs material system. A highly doped InGaAs base layer and a collector layer are fabricated from the layered structure in a triple mesa process. The transistor includes two separate emitter fingers, each having dimensions of 0.8 by 12 m. The common-base configuration was chosen for its high maximum stable gain in the frequency band of interest. The input-matching network is designed for high bandwidth. The output of the transistor is matched to a load line for maximum saturated output power under large-signal conditions, rather than being matched for maximum gain under small-signal conditions. In a test at a frequency of 172 GHz, the amplifier was found to generate an output power of 7.5 mW, with approximately 5 dB of large-signal gain (see Figure 2). Moreover, the amplifier exhibited a peak small-signal gain of 7 dB at a frequency of 176 GHz. This performance of this MMIC single-stage amplifier containing only a single transistor represents a significant advance in the state of the art, in that it rivals the 170-GHz performance of a prior MMIC three-stage, four-transistor amplifier. [The prior amplifier was reported in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11 (November 2003), page 49.] This amplifier is the first heterojunction- bipolar-transistor (HBT) amplifier built for medium power operation in this

  19. Gyromagnetron amplifier

    SciTech Connect

    Lau, Y.-Y.; Barnett, L. R.

    1985-10-29

    A gyromagnetron amplifier for radiation at millimeter wavelengths comprising a tapered waveguide tube with longitudinally running vanes in the walls of the tube with the number of vanes chosen to coincide with a desired cyclotron harmonic frequency to be amplified. A beam of spiralling mildly relativistic electrons with an energy of 100 keV or less is directed into the small end of the tapered waveguide tube. A tapered axial magnetic field is set up within the waveguide tube with a low value appropriate to the amplification of a cyclotron harmonic frequency. An electromagnetic wave to be amplified is launched into the waveguide tube to co-propagate and be amplified by the spiralling electron beam. This device is characterized by a wide bandwidth, a low operating magnetic field, a relatively low operating beam voltage, with high power, and the capability of continuous wave operation.

  20. High-efficiency solid state power amplifier

    NASA Technical Reports Server (NTRS)

    Wallis, Robert E. (Inventor); Cheng, Sheng (Inventor)

    2005-01-01

    A high-efficiency solid state power amplifier (SSPA) for specific use in a spacecraft is provided. The SSPA has a mass of less than 850 g and includes two different X-band power amplifier sections, i.e., a lumped power amplifier with a single 11-W output and a distributed power amplifier with eight 2.75-W outputs. These two amplifier sections provide output power that is scalable from 11 to 15 watts without major design changes. Five different hybrid microcircuits, including high-efficiency Heterostructure Field Effect Transistor (HFET) amplifiers and Monolithic Microwave Integrated Circuit (MMIC) phase shifters have been developed for use within the SSPA. A highly efficient packaging approach enables the integration of a large number of hybrid circuits into the SSPA.

  1. Wide-Temperature-Range Integrated Operational Amplifier

    NASA Technical Reports Server (NTRS)

    Mojarradi, Mohammad; Levanas, Greg; Chen, Yuan; Kolawa, Elizabeth; Cozy, Raymond; Blalock, Benjamin; Greenwell, Robert; Terry, Stephen

    2007-01-01

    A document discusses a silicon-on-insulator (SOI) complementary metal oxide/semiconductor (CMOS) integrated- circuit operational amplifier to be replicated and incorporated into sensor and actuator systems of Mars-explorer robots. This amplifier is designed to function at a supply potential less than or equal to 5.5 V, at any temperature from -180 to +120 C. The design is implemented on a commercial radiation-hard SOI CMOS process rated for a supply potential of less than or equal to 3.6 V and temperatures from -55 to +110 C. The design incorporates several innovations to achieve this, the main ones being the following: NMOS transistor channel lengths below 1 m are generally not used because research showed that this change could reduce the adverse effect of hot carrier injection on the lifetimes of transistors at low temperatures. To enable the amplifier to withstand the 5.5-V supply potential, a circuit topology including cascade devices, clamping devices, and dynamic voltage biasing was adopted so that no individual transistor would be exposed to more than 3.6 V. To minimize undesired variations in performance over the temperature range, the transistors in the amplifier are biased by circuitry that maintains a constant inversion coefficient over the temperature range.

  2. High-Efficiency Microwave Power Amplifier

    NASA Technical Reports Server (NTRS)

    Sims, Williams H.

    2005-01-01

    A high-efficiency power amplifier that operates in the S band (frequencies of the order of a few gigahertz) utilizes transistors operating under class-D bias and excitation conditions. Class-D operation has been utilized at lower frequencies, but, until now, has not been exploited in the S band. Nominally, in class D operation, a transistor is switched rapidly between "on" and "off" states so that at any given instant, it sustains either high current or high voltage, but not both at the same time. In the ideal case of zero "on" resistance, infinite "off" resistance, zero inductance and capacitance, and perfect switching, the output signal would be a perfect square wave. Relative to the traditional classes A, B, and C of amplifier operation, class D offers the potential to achieve greater power efficiency. In addition, relative to class-A amplifiers, class-D amplifiers are less likely to go into oscillation. In order to design this amplifier, it was necessary to derive mathematical models of microwave power transistors for incorporation into a larger mathematical model for computational simulation of the operation of a class-D microwave amplifier. The design incorporates state-of-the-art switching techniques applicable only in the microwave frequency range. Another major novel feature is a transmission-line power splitter/combiner designed with the help of phasing techniques to enable an approximation of a square-wave signal (which is inherently a wideband signal) to propagate through what would, if designed in a more traditional manner, behave as a more severely band-limited device (see figure). The amplifier includes an input, a driver, and a final stage. Each stage contains a pair of GaAs-based field-effect transistors biased in class D. The input signal can range from -10 to +10 dBm into a 50-ohm load. The table summarizes the performances of the three stages

  3. Superconducting transistor

    DOEpatents

    Gray, Kenneth E.

    1979-01-01

    A superconducting transistor is formed by disposing three thin films of superconducting material in a planar parallel arrangement and insulating the films from each other by layers of insulating oxides to form two tunnel junctions. One junction is biased above twice the superconducting energy gap and the other is biased at less than twice the superconducting energy gap. Injection of quasiparticles into the center film by one junction provides a current gain in the second junction.

  4. LOGARITHMIC AMPLIFIER

    DOEpatents

    Wade, E.J.; Stone, R.S.

    1959-03-10

    Electronic,amplifier circuits, especially a logai-ithmic amplifier characterizxed by its greatly improved strability are discussed. According to the in ention, means are provided to feed bach the output valtagee to a diode in the amplifier input circuit, the diode being utilized to produce the logarithmic characteristics. The diode is tics, The diode isition therewith and having its filament operated from thc same source s the filament of the logarithmic diode. A bias current of relatively large value compareii with the signal current is continuously passed through the compiting dioie to render the diode insensitivy to variations in the signal current. by this odes kdu to variaelled, so that the stability of the amlifier will be unimpaired.

  5. Bidirectional amplifier

    DOEpatents

    Wright, James T.

    1986-01-01

    A bilateral circuit is operable for transmitting signals in two directions without generation of ringing due to feedback caused by the insertion of the circuit. The circuit may include gain for each of the signals to provide a bidirectional amplifier. The signals are passed through two separate paths, with a unidirectional amplifier in each path. A controlled sampling device is provided in each path for sampling the two signals. Any feedback loop between the two signals is disrupted by providing a phase displacement between the control signals for the two sampling devices.

  6. Bidirectional amplifier

    DOEpatents

    Wright, J.T.

    1984-02-02

    A bilateral circuit is operable for transmitting signals in two directions without generation of ringing due to feedback caused by the insertion of the circuit. The circuit may include gain for each of the signals to provide a bidirectional amplifier. The signals are passed through two separate paths, with a unidirectional amplifier in each path. A controlled sampling device is provided in each path for sampling the two signals. Any feedback loop between the two signals is disrupted by providing a phase displacement between the control signals for the two sampling devices.

  7. Amplified Policymaking

    ERIC Educational Resources Information Center

    Prince, Katherine; Woempner, Carolyn

    2010-01-01

    This brief examines the policy implications of two drivers of change presented in the "2020 Forecast: Creating the Future of Learning"-- Pattern Recognition and Amplified Organization. These drivers point toward a series of cultural shifts and illuminate how we are developing new ways of organizing, constructing, and managing knowledge.…

  8. Hafnium transistor design for neural interfacing.

    PubMed

    Parent, David W; Basham, Eric J

    2008-01-01

    A design methodology is presented that uses the EKV model and the g(m)/I(D) biasing technique to design hafnium oxide field effect transistors that are suitable for neural recording circuitry. The DC gain of a common source amplifier is correlated to the structural properties of a Field Effect Transistor (FET) and a Metal Insulator Semiconductor (MIS) capacitor. This approach allows a transistor designer to use a design flow that starts with simple and intuitive 1-D equations for gain that can be verified in 1-D MIS capacitor TCAD simulations, before final TCAD process verification of transistor properties. The DC gain of a common source amplifier is optimized by using fast 1-D simulations and using slower, complex 2-D simulations only for verification. The 1-D equations are used to show that the increased dielectric constant of hafnium oxide allows a higher DC gain for a given oxide thickness. An additional benefit is that the MIS capacitor can be employed to test additional performance parameters important to an open gate transistor such as dielectric stability and ionic penetration.

  9. Test results for 20-GHz GaAs FET spacecraft power amplifier

    NASA Technical Reports Server (NTRS)

    Shalkhauser, K. A.

    1985-01-01

    Test were conducted to measure the performance of the 20-GHz solid state, proof-of-concept amplifier. The amplifier operates over the 17.7 to 20.2-GHz frequency range and uses high power gallium arsenide field effect transistors. The amplifier design and test methods are briefly described. NASA and contractor performance data are compared.

  10. Organic electrochemical transistors for clinical applications.

    PubMed

    Leleux, Pierre; Rivnay, Jonathan; Lonjaret, Thomas; Badier, Jean-Michel; Bénar, Christian; Hervé, Thierry; Chauvel, Patrick; Malliaras, George G

    2015-01-01

    The ability of organic electrochemical transistors is explored to record human electrophysiological signals of clinical relevance. An organic electrochemical transistor (OECT) that shows a high (>1 mS) transconductance at zero applied gate voltage is used, necessitating only one power supply to bias the drain, while the gate circuit is driven by cutaneous electrical potentials. The OECT is successful in recording cardiac rhythm, eye movement, and brain activity of a human volunteer. These results pave the way for applications of OECTs as an amplifying transducer for human electrophysiology.

  11. Cryogenic Amplifier Based Receivers at Submillimeter Wavelengths

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Reck, Theodore and; Schlecht, Erich; Lin, Robert; Deal, William

    2012-01-01

    The operating frequency of InP high electron mobility transistor (HEMT) based amplifiers has moved well in the submillimeter-wave frequencies over the last couple of years. Working amplifiers with usable gain in waveguide packages has been reported beyond 700 GHz. When cooled cryogenically, they have shown substantial improvement in their noise temperature. This has opened up the real possibility of cryogenic amplifier based heterodyne receivers at submillimeter wavelengths for ground-based, air-borne, and space-based instruments for astrophysics, planetary, and Earth science applications. This paper provides an overview of the science applications at submillimeter wavelengths that will benefit from this technology. It also describes the current state of the InP HEMT based cryogenic amplifier receivers at submillimeter wavelengths.

  12. High-gain amplifier has excellent stability and low power consumption

    NASA Technical Reports Server (NTRS)

    Kleinberg, L. L.

    1965-01-01

    Transistorized amplifier, in which an external reference voltage controls gain, combines high gain with stability and low power consumption. This circuit is useful in electronic servo and portable audio equipment.

  13. Digitally gain controlled linear high voltage amplifier for laboratory applications.

    PubMed

    Koçum, C

    2011-08-01

    The design of a digitally gain controlled high-voltage non-inverting bipolar linear amplifier is presented. This cost efficient and relatively simple circuit has stable operation range from dc to 90 kHz under the load of 10 kΩ and 39 pF. The amplifier can swing up to 360 V(pp) under these conditions and it has 2.5 μs rise time. The gain can be changed by the aid of JFETs. The amplifiers have been realized using a combination of operational amplifiers and high-voltage discrete bipolar junction transistors. The circuit details and performance characteristics are discussed.

  14. Time-reversal duality of high-efficiency RF power amplifiers

    SciTech Connect

    Reveyrand, T; Ramos, I; Popovic, Z

    2012-12-06

    The similarity between RF power amplifiers and rectifiers is discussed. It is shown that the same high-efficiency harmonically-terminated power amplifier can be operated in a dual rectifier mode. Nonlinear simulations with a GaN HEMT transistor model show the time-reversal intrinsic voltage and current waveform relationship between a class-F amplifier and rectifier. Measurements on a class-F-1 amplifier and rectifier at 2.14 GHz demonstrate over 80% efficiency in both cases.

  15. Power-Amplifier Module for 145 to 165 GHz

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Peralta, Alejandro

    2007-01-01

    A power-amplifier module that operates in the frequency range of 145 to 165 GHz has been designed and constructed as a combination of (1) a previously developed monolithic microwave integrated circuit (MMIC) power amplifier and (2) a waveguide module. The amplifier chip was needed for driving a high-electron-mobility-transistor (HEMT) frequency doubler. While it was feasible to connect the amplifier and frequency-doubler chips by use of wire bonds, it was found to be much more convenient to test the amplifier and doubler chips separately. To facilitate separate testing, it was decided to package the amplifier and doubler chips in separate waveguide modules. Figure 1 shows the resulting amplifier module. The amplifier chip was described in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11, (November 2003), page 49. To recapitulate: This is a three-stage MMIC power amplifier that utilizes HEMTs as gain elements. The amplifier was originally designed to operate in the frequency range of 140 to 170 GHz. The waveguide module is based on a previously developed lower frequency module, redesigned to support operation in the frequency range of 140 to 220 GHz. Figure 2 presents results of one of several tests of the amplifier module - measurements of output power and gain as functions of input power at an output frequency of 150 GHz. Such an amplifier module has many applications to test equipment for power sources above 100 GHz.

  16. Precision absolute value amplifier for a precision voltmeter

    DOEpatents

    Hearn, William E.; Rondeau, Donald J.

    1985-01-01

    Bipolar inputs are afforded by the plus inputs of first and second differential input amplifiers. A first gain determining resister is connected between the minus inputs of the differential amplifiers. First and second diodes are connected between the respective minus inputs and the respective outputs of the differential amplifiers. First and second FETs have their gates connected to the outputs of the amplifiers, while their respective source and drain circuits are connected between the respective minus inputs and an output lead extending to a load resister. The output current through the load resister is proportional to the absolute value of the input voltage difference between the bipolar input terminals. A third differential amplifier has its plus input terminal connected to the load resister. A second gain determining resister is connected between the minus input of the third differential amplifier and a voltage source. A third FET has its gate connected to the output of the third amplifier. The source and drain circuit of the third transistor is connected between the minus input of the third amplifier and a voltage-frequency converter, constituting an output device. A polarity detector is also provided, comprising a pair of transistors having their inputs connected to the outputs of the first and second differential amplifiers. The outputs of the polarity detector are connected to gates which switch the output of the voltage-frequency converter between up and down counting outputs.

  17. Precision absolute-value amplifier for a precision voltmeter

    DOEpatents

    Hearn, W.E.; Rondeau, D.J.

    1982-10-19

    Bipolar inputs are afforded by the plus inputs of first and second differential input amplifiers. A first gain determining resistor is connected between the minus inputs of the differential amplifiers. First and second diodes are connected between the respective minus inputs and the respective outputs of the differential amplifiers. First and second FETs have their gates connected to the outputs of the amplifiers, while their respective source and drain circuits are connected between the respective minus inputs and an output lead extending to a load resistor. The output current through the load resistor is proportional to the absolute value of the input voltage difference between the bipolar input terminals. A third differential amplifier has its plus input terminal connected to the load resistor. A second gain determining resistor is connected between the minus input of the third differential amplifier and a voltage source. A third FET has its gate connected to the output of the third amplifier. The source and drain circuit of the third transistor is connected between the minus input of the third amplifier and a voltage-frequency converter, constituting an output device. A polarity detector is also provided, comprising a pair of transistors having their inputs connected to the outputs of the first and second differential amplifiers. The outputs of the polarity detector are connected to gates which switch the output of the voltage-frequency converter between up and down counting outputs.

  18. Low cost instrumentation amplifier

    NASA Technical Reports Server (NTRS)

    Sturman, J. C.

    1974-01-01

    Amplifier can be used for many applications requiring high input impedance and common mode rejection, low drift, and gain accuracy on order of one percent. Performance of inexpensive amplifier approaches that of some commercial instrumentation amplifiers in many specifications.

  19. Crystal oscillators using negative voltage gain, single pole response amplifiers

    NASA Technical Reports Server (NTRS)

    Kleinberg, Leonard L. (Inventor)

    1989-01-01

    A simple and inexpensive crystal oscillator is provided which employs negative voltage gain, single pole response amplifiers. The amplifiers may include such configurations as gate inverters, operational amplifiers and conventional bipolar transistor amplifiers, all of which operate at a frequency which is on the roll-off portion of their gain versus frequency curve. Several amplifier feedback circuit variations are employed to set desired bias levels and to allow the oscillator to operate at the crystal's fundamental frequency or at an overtone of the fundamental frequency. The oscillator is made less expensive than comparable oscillators by employing relatively low frequency amplifiers and operating them at roll-off, at frequencies beyond which they are customarily used. Simplicity is provided because operation at roll-off eliminates components ordinarily required in similar circuits to provide sufficient phase-shift in the feedback circuitry for oscillation to occur.

  20. Compact, Single-Stage MMIC InP HEMT Amplifier

    NASA Technical Reports Server (NTRS)

    Pukala, David; Samoska, Lorene; Fung, King Man; Gaier, Todd; Deal, W. R.; Mei, Gerry; Radisic, Vesna; Lai, Richard

    2008-01-01

    A monolithic micro - wave integrated-circuit (MMIC) singlestage amplifier containing an InP-based high-electron-mobility transistor (HEMT) plus coplanar-waveguide (CPW) transmission lines for impedance matching and input and output coupling, all in a highly miniaturized layout as needed for high performance at operating frequencies of hundreds of gigahertz is described.

  1. A 90 GHz Amplifier Assembled Using Flip-Chip Technology

    NASA Technical Reports Server (NTRS)

    Samoska, L.; Pinsukanjana, P.; Gaier, T.; Smith, R.; Ksendzov, A.; Fitzsimmons, M.; Martin, S.; Lai, R.

    1999-01-01

    This letter reports the performance of a novel single-stage W-band amplifier fabricated utilizing flip-chip bump-bonding. We have bump-bonded a high-speed, low-noise InP high electron mobility transistor (HEMT) device onto a separately fabricated passive circuit having a GaAs substrate.

  2. EDITORIAL: Reigniting innovation in the transistor Reigniting innovation in the transistor

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2012-09-01

    Today the transistor is integral to the electronic circuitry that wires our lives. When Bardeen and Brattain first observed an amplified signal by connecting electrodes to a germanium crystal they saw that their 'semiconductor triode' could prove a useful alternative to the more cumbersome vacuum tubes used at the time [1]. But it was perhaps William Schottky who recognized the extent of the transistor's potential. A basic transistor has three or more terminals and current across one pair of terminals can switch or amplify current through another pair. Bardeen, Brattain and Schottky were jointly awarded a Nobel Prize in 1956 'for their researches on semiconductors and their discovery of the transistor effect' [2]. Since then many new forms of the transistor have been developed and understanding of the underlying properties is constantly advancing. In this issue Chen and Shih and colleagues at Taiwan National University and Drexel University report a pyroelectrics transistor. They show how a novel optothermal gating mechanism can modulate the current, allowing a range of developments in nanoscale optoelectronics and wireless devices [3]. The explosion of interest in nanoscale devices in the 1990s inspired electronics researchers to look for new systems that can act as transistors, such as carbon nanotube [4] and silicon nanowire [5] transistors. Generally these transistors function by raising and lowering an energy barrier of kBT -1, but researchers in the US and Canada have demonstrated that the quantum interference between two electronic pathways through aromatic molecules can also modulate the current flow [6]. The device has advantages for further miniaturization where energy dissipation in conventional systems may eventually cause complications. Interest in transistor technology has also led to advances in fabrication techniques for achieving high production quantities, such as printing [7]. Researchers in Florida in the US demonstrated field effect transistor

  3. MMIC Amplifier Produces Gain of 10 dB at 235 GHz

    NASA Technical Reports Server (NTRS)

    Dawson, Douglas; Fung, King Man; Lee, Karen; Samoska, Lorene; Wells, Mary; Gaier, Todd; Kangaslahti, Pekka; Grundbacher, Ronald; Lai, Richard; Raja, Rohit; Liu, Po-Hsin

    2007-01-01

    The first solid-state amplifier capable of producing gain at a frequency >215 GHz has been demonstrated. This amplifier was fabricated as a monolithic microwave integrated-circuit (MMIC) chip containing InP high-electron-mobility transistors (HEMTs) of 0.07 micron gate length on a 50- m-thick InP substrate.

  4. Near-Field Thermal Transistor

    NASA Astrophysics Data System (ADS)

    Ben-Abdallah, Philippe; Biehs, Svend-Age

    2014-01-01

    Using a block of three separated solid elements, a thermal source and drain together with a gate made of an insulator-metal transition material exchanging near-field thermal radiation, we introduce a nanoscale analog of a field-effect transistor that is able to control the flow of heat exchanged by evanescent thermal photons between two bodies. By changing the gate temperature around its critical value, the heat flux exchanged between the hot body (source) and the cold body (drain) can be reversibly switched, amplified, and modulated by a tiny action on the gate. Such a device could find important applications in the domain of nanoscale thermal management and it opens up new perspectives concerning the development of contactless thermal circuits intended for information processing using the photon current rather than the electric current.

  5. SQUARE WAVE AMPLIFIER

    DOEpatents

    Leavitt, M.A.; Lutz, I.C.

    1958-08-01

    An amplifier circuit is described for amplifying sigmals having an alternating current component superimposed upon a direct current component, without loss of any segnnent of the alternating current component. The general circuit arrangement includes a vibrator, two square wave amplifiers, and recombination means. The amplifier input is connected to the vibrating element of the vibrator and is thereby alternately applied to the input of each square wave amplifier. The detailed circuitry of the recombination means constitutes the novelty of the annplifier and consists of a separate, dual triode amplifier coupled to the output of each square wave amplifier with a recombination connection from the plate of one amplifier section to a grid of one section of the other amplifier. The recombination circuit has provisions for correcting distortion caused by overlapping of the two square wave voltages from the square wave amplifiers.

  6. X-Band, 17-Watt Solid-State Power Amplifier

    NASA Technical Reports Server (NTRS)

    Mittskus, Anthony; Stone, Ernest; Boger, William; Burgess, David; Honda, Richard; Nuckolls, Carl

    2005-01-01

    An advanced solid-state power amplifier that can generate an output power of as much as 17 W at a design operating frequency of 8.4 GHz has been designed and constructed as a smaller, lighter, less expensive alternative to traveling-wave-tube X-band amplifiers and to prior solid-state X-band power amplifiers of equivalent output power. This amplifier comprises a monolithic microwave integrated circuit (MMIC) amplifier module and a power-converter module integrated into a compact package (see Figure 1). The amplifier module contains an input variable-gain amplifier (VGA), an intermediate driver stage, a final power stage, and input and output power monitors (see Figure 2). The VGA and the driver amplifier are 0.5-m GaAs-based metal semiconductor field-effect transistors (MESFETs). The final power stage contains four parallel high-efficiency, GaAs-based pseudomorphic high-electron-mobility transistors (PHEMTs). The gain of the VGA is voltage-variable over a range of 10 to 24 dB. To provide for temperature compensation of the overall amplifier gain, the gain-control voltage is generated by an operational-amplifier circuit that includes a resistor/thermistor temperature-sensing network. The driver amplifier provides a gain of 14 dB to an output power of 27 dBm to drive the four parallel output PHEMTs, each of which is nominally capable of putting out as much as 5 W. The driver output is sent to the input terminals of the four parallel PHEMTs through microstrip power dividers; the outputs of these PHEMTs are combined by microstrip power combiners (which are similar to the microstrip power dividers) to obtain the final output power of 17 W.

  7. Segmented amplifier configurations for laser amplifier

    DOEpatents

    Hagen, Wilhelm F.

    1979-01-01

    An amplifier system for high power lasers, the system comprising a compact array of segments which (1) preserves high, large signal gain with improved pumping efficiency and (2) allows the total amplifier length to be shortened by as much as one order of magnitude. The system uses a three dimensional array of segments, with the plane of each segment being oriented at substantially the amplifier medium Brewster angle relative to the incident laser beam and with one or more linear arrays of flashlamps positioned between adjacent rows of amplifier segments, with the plane of the linear array of flashlamps being substantially parallel to the beam propagation direction.

  8. Hybrid matrix amplifier

    DOEpatents

    Martens, J.S.; Hietala, V.M.; Plut, T.A.

    1995-01-03

    The present invention comprises a novel matrix amplifier. The matrix amplifier includes an active superconducting power divider (ASPD) having N output ports; N distributed amplifiers each operatively connected to one of the N output ports of the ASPD; and a power combiner having N input ports each operatively connected to one of the N distributed amplifiers. The distributed amplifier can included M stages of amplification by cascading superconducting active devices. The power combiner can include N active elements. The resulting (N[times]M) matrix amplifier can produce signals of high output power, large bandwidth, and low noise. 6 figures.

  9. Hybrid matrix amplifier

    DOEpatents

    Martens, Jon S.; Hietala, Vincent M.; Plut, Thomas A.

    1995-01-01

    The present invention comprises a novel matrix amplifier. The matrix amplifier includes an active superconducting power divider (ASPD) having N output ports; N distributed amplifiers each operatively connected to one of the N output ports of the ASPD; and a power combiner having N input ports each operatively connected to one of the N distributed amplifiers. The distributed amplifier can included M stages of amplification by cascading superconducting active devices. The power combiner can include N active elements. The resulting (N.times.M) matrix amplifier can produce signals of high output power, large bandwidth, and low noise.

  10. Portable musical instrument amplifier

    DOEpatents

    Christian, David E.

    1990-07-24

    The present invention relates to a musical instrument amplifier which is particularly useful for electric guitars. The amplifier has a rigid body for housing both the electronic system for amplifying and processing signals from the guitar and the system's power supply. An input plug connected to and projecting from the body is electrically coupled to the signal amplifying and processing system. When the plug is inserted into an output jack for an electric guitar, the body is rigidly carried by the guitar, and the guitar is operatively connected to the electrical amplifying and signal processing system without use of a loose interconnection cable. The amplifier is provided with an output jack, into which headphones are plugged to receive amplified signals from the guitar. By eliminating the conventional interconnection cable, the amplifier of the present invention can be used by musicians with increased flexibility and greater freedom of movement.

  11. Gain and switching in the spin-flip transistor

    NASA Astrophysics Data System (ADS)

    Bauer, Gerrit E. W.; Brataas, Arne; Tserkovnyak, Yaroslav

    2003-03-01

    The transport properties of multi-terminal magnetoelectronic structures in the diffuse regime can be calculated conveniently by magnetoelectronic circuit theory [1]. The "spin-flip transistor" is a device consisting of a normal metal node and three ferromagnetic contacts with magnetization directions that can be rotated freely. We discuss the circuit theory of the spin-flip transistor when used as current or voltage amplifier, as a memory element, or spin injector. [1] A. Brataas, Yu.V. Nazarov, and G.E.W. Bauer, Phys. Rev. Lett. 84, 2481 (2000).

  12. Amplified spontaneous emission in Cassegrainian amplifiers

    NASA Astrophysics Data System (ADS)

    Eimerl, David

    1987-05-01

    The paper considers all possible paths for amplifed spontaneous emission (ASE) in multipass laser amplifiers using a Cassegranian telescope geometry. In particular, ASE which is reflected back into the medium off the telescope mirrors themselves is studied. These ASE components are unavoidable in this amplifier geometry. It is shown that there is a component of the ASE which makes approximately double the number of passes through the amplifier as the laser signal makes. It is also shown that these high-order ASE components are also present in amplifiers which are almost Cassegrainian. They cannot be eliminated by changing the ratio of the scraper and hole radii or the separation of the mirrors. It is likely that these ASE components will be more significant in pulsed lasers than CW lasers.

  13. Laser amplifier chain

    DOEpatents

    Hackel, R.P.

    1992-10-20

    A laser amplifier chain has a plurality of laser amplifiers arranged in a chain to sequentially amplify a low-power signal beam to produce a significantly higher-power output beam. Overall efficiency of such a chain is improved if high-gain, low efficiency amplifiers are placed on the upstream side of the chain where only a very small fraction of the total pumped power is received by the chain and low-gain, high-efficiency amplifiers are placed on the downstream side where a majority of pumping energy is received by the chain. 6 figs.

  14. Laser amplifier chain

    DOEpatents

    Hackel, Richard P.

    1992-01-01

    A laser amplifier chain has a plurality of laser amplifiers arranged in a chain to sequentially amplify a low-power signal beam to produce a significantly higher-power output beam. Overall efficiency of such a chain is improved if high-gain, low efficiency amplifiers are placed on the upstream side of the chain where only a very small fraction of the total pumped power is received by the chain and low-gain, high-efficiency amplifiers are placed on the downstream side where a majority of pumping energy is received by the chain.

  15. High Power Switching Transistor

    NASA Technical Reports Server (NTRS)

    Hower, P. L.; Kao, Y. C.; Carnahan, D. C.

    1983-01-01

    Improved switching transistors handle 400-A peak currents and up to 1,200 V. Using large diameter silicon wafers with twice effective area as D60T, form basis for D7 family of power switching transistors. Package includes npn wafer, emitter preform, and base-contact insert. Applications are: 25to 50-kilowatt high-frequency dc/dc inverters, VSCF converters, and motor controllers for electrical vehicles.

  16. Black Phosphorus RF Transistor

    NASA Astrophysics Data System (ADS)

    Wang, Han; Wang, Xiaomu; Xia, Fengnian; Wang, Luhao; Jiang, Hao; Xia, Qiangfei; Chin, Mattew L.; Dubey, Madan; Han, Shu-Jen

    2015-03-01

    Few-layer and thin film form of layered black phosphorus (BP) has recently emerged as a promising material for applications in high performance thin film electronics and infrared optoelectronics. Layered BP offers a ~ 0.3eV bandgap and high mobility, leading to transistor devices with decent on/off ratio and high on-state current density. Here, we demonstrate the GHz frequency operation of black phosphorus field-effect transistor for the first time. BP transistors demonstrated here show excellent current saturation with an on-off ratio exceeding 2 × 103. The S-parameter characterization is performed for the first time on black phosphorus transistors, giving a 12 GHz short-circuit current-gain cut-off frequency and 20 GHz maximum oscillation frequency in 300 nm channel length devices. A current density in excess of 270 mA/mm and DC transconductance above 180 mS/mm are achieved for hole conductions. The results reveal the promising potential of black phosphorus transistors for enabling the next generation thin film transistor technology that can operate in the multi-GHz frequency range and beyond.

  17. From The Lab to The Fab: Transistors to Integrated Circuits

    NASA Astrophysics Data System (ADS)

    Huff, Howard R.

    2003-09-01

    Transistor action was experimentally observed by John Bardeen and Walter Brattain in n-type polycrystalline germanium on December 16, 1947 (and subsequently polycrystalline silicon) as a result of the judicious placement of gold-plated probe tips in nearby single crystal grains of the polycrystalline material (i.e., the point-contact semiconductor amplifier, often referred to as the point-contact transistor).The device configuration exploited the inversion layer as the channel through which most of the emitted (minority) carriers were transported from the emitter to the collector. The point-contact transistor was manufactured for ten years starting in 1951 by the Western Electric Division of AT&T. The a priori tuning of the point-contact transistor parameters, however, was not simple inasmuch as the device was dependent on the detailed surface structure and, therefore, very sensitive to humidity and temperature as well as exhibiting high noise levels. Accordingly, the devices differed significantly in their characteristics and electrical instabilities leading to "burnout" were not uncommon. With the implementation of crystalline semiconductor materials in the early 1950s, however, p-n junction (bulk) transistors began replacing the point-contact transistor, silicon began replacing germanium and the transfer of transistor technology from the lab to the lab accelerated. We shall review the historical route by which single crystalline materials were developed and the accompanying methodologies of transistor fabrication, leading to the onset of the Integrated Circuit (IC) era. Finally, highlights of the early years of the IC era will be reviewed from the 256 bit through the 4M DRAM. Elements of IC scaling and the role of Moore's Law in setting the parameters by which the IC industry's growth was monitored will be discussed.

  18. Transistor-based interface circuitry

    DOEpatents

    Taubman, Matthew S.

    2004-02-24

    Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

  19. Transistor-based interface circuitry

    DOEpatents

    Taubman, Matthew S.

    2007-02-13

    Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

  20. Teaching the Common Emitter Amplifier.

    ERIC Educational Resources Information Center

    Ellse, Mark D.

    1984-01-01

    Describes experiments in which a bipolar transistor is used to examine the behavior of a simple circuit. Also addresses problems in teaching the related concepts. (The experiments can be modified to incorporate devices other than bipolar transistors.) (JN)

  1. Preventing Simultaneous Conduction In Switching Transistors

    NASA Technical Reports Server (NTRS)

    Mclyman, William T.

    1990-01-01

    High voltage spikes and electromagnetic interference suppressed. Power-supply circuit including two switching transistors easily modified to prevent simultaneous conduction by both transistors during switching intervals. Diode connected between collector of each transistor and driving circuit for opposite transistor suppresses driving signal to transistor being turned on until transistor being turned off ceases to carry current.

  2. A single-molecule optical transistor.

    PubMed

    Hwang, J; Pototschnig, M; Lettow, R; Zumofen, G; Renn, A; Götzinger, S; Sandoghdar, V

    2009-07-01

    The transistor is one of the most influential inventions of modern times and is ubiquitous in present-day technologies. In the continuing development of increasingly powerful computers as well as alternative technologies based on the prospects of quantum information processing, switching and amplification functionalities are being sought in ultrasmall objects, such as nanotubes, molecules or atoms. Among the possible choices of signal carriers, photons are particularly attractive because of their robustness against decoherence, but their control at the nanometre scale poses a significant challenge as conventional nonlinear materials become ineffective. To remedy this shortcoming, resonances in optical emitters can be exploited, and atomic ensembles have been successfully used to mediate weak light beams. However, single-emitter manipulation of photonic signals has remained elusive and has only been studied in high-finesse microcavities or waveguides. Here we demonstrate that a single dye molecule can operate as an optical transistor and coherently attenuate or amplify a tightly focused laser beam, depending on the power of a second 'gating' beam that controls the degree of population inversion. Such a quantum optical transistor has also the potential for manipulating non-classical light fields down to the single-photon level. We discuss some of the hurdles along the road towards practical implementations, and their possible solutions. PMID:19571881

  3. Organic transistors for electrophysiology (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Rivnay, Jonathan

    2015-10-01

    Efficient local transduction of biological signals is of critical importance for mapping brain activity and diagnosing pathological conditions. Traditional devices used to record electrophysiological signals are passive electrodes that require (pre)amplification with downstream electronics. Organic electrochemical transistors (OECTs) that utilize conducting polymer films as the channel have shown considerable promise as amplifying transducers due to their stability in aqueous conditions and high transconductance (>3 mS). The materials properties and physics of such transistors, however, remains largely unexplored thus limiting their potential. Here we show that the uptake of ionic charge from an electrolyte into a poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) OECT channel leads to a dependence of the effective capacitance on the entire volume of the film. Subsequently, device transconductance and time response vary with channel thickness, a defining characteristic that differentiates OECTs from field effect transistors, and provides a new degree of freedom for device engineering. Using this understanding we tailor OECTs for a variety of low (1-100 Hz) and high (1-10 kHz) frequency applications, including human electroencephalography, where high transconductance devices impart richer signal content without the need for additional amplification circuitry. We also show that the materials figure of merit OECTs is the product of hole mobility and volumetric capacitance of the channel, leading to design rules for novel high performance materials.

  4. Resistor-less charge sensitive amplifier for semiconductor detectors

    NASA Astrophysics Data System (ADS)

    Pelczar, K.; Panas, K.; Zuzel, G.

    2016-11-01

    A new concept of a Charge Sensitive Amplifier without a high-value resistor in the feedback loop is presented. Basic spectroscopic parameters of the amplifier coupled to a coaxial High Purity Germanium detector (HPGe) are discussed. The amplifier signal input is realized with an n-channel J-FET transistor. The feedback capacitor is discharged continuously by the second, forward biased n-channel J-FET, driven by an RC low-pass filter. Both the analog-with a standard spectroscopy amplifier and a multi-channel analyzer-and the digital-by applying a Flash Analog to Digital Converter-signal readouts were tested. The achieved resolution in the analog and the digital readouts was 0.17% and 0.21%, respectively, at the Full Width at Half Maximum of the registered 60Co 1332.5 keV gamma line.

  5. Update on Waveguide-Embedded Differential MMIC Amplifiers

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka; Schleht, Erich

    2010-01-01

    There is an update on the subject matter of Differential InP HEMT MMIC Amplifiers Embedded in Waveguides (NPO-42857) NASA Tech Briefs, Vol. 33, No. 9 (September 2009), page 35. To recapitulate: Monolithic microwave integrated-circuit (MMIC) amplifiers of a type now being developed for operation at frequencies of hundreds of gigahertz contain InP high-electron-mobility transistors (HEMTs) in a differential configuration. The MMICs are designed integrally with, and embedded in, waveguide packages. The instant work does not mention InP HEMTs but otherwise reiterates part of the subject matter of the cited prior article, with emphasis on the following salient points: An MMIC is mounted in the electric-field plane ("E-plane") of a waveguide and includes a finline transition to each differential-amplifier stage. The differential configuration creates a virtual ground within each pair of transistor-gate fingers, eliminating the need for external radio-frequency grounding. This work concludes by describing a single-stage differential submillimeter-wave amplifier packaged in a rectangular waveguide and summarizing results of tests of this amplifier at frequencies of 220 and 305 GHz.

  6. Wireless Josephson amplifier

    SciTech Connect

    Narla, A.; Sliwa, K. M.; Hatridge, M.; Shankar, S.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

    2014-06-09

    Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables, and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement efficiency and amplifier tunability. We have developed a wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the 9–11 GHz band with about 100 MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability.

  7. Compact laser amplifier system

    DOEpatents

    Carr, R.B.

    1974-02-26

    A compact laser amplifier system is described in which a plurality of face-pumped annular disks, aligned along a common axis, independently radially amplify a stimulating light pulse. Partially reflective or lasing means, coaxially positioned at the center of each annualar disk, radially deflects a stimulating light directed down the common axis uniformly into each disk for amplification, such that the light is amplified by the disks in a parallel manner. Circumferential reflecting means coaxially disposed around each disk directs amplified light emission, either toward a common point or in a common direction. (Official Gazette)

  8. A new bipolar transistor - GAT

    NASA Astrophysics Data System (ADS)

    Kondo, H.; Yukimoto, Y.

    1980-02-01

    A new bipolar transistor named Gate Associated Transistor (GAT) was proposed and the operating mechanisms were verified. The structure of the GAT has a unique base region consisting of an FET merged into the base of a standard bipolar transistor. The operating mechanisms and characteristics of the GAT were investigated and compared with those of standard power transistors. The most outstanding feature of the GAT was a large area for safe operation.

  9. Linearly polarized fiber amplifier

    SciTech Connect

    Kliner, Dahv A.; Koplow, Jeffery P.

    2004-11-30

    Optically pumped rare-earth-doped polarizing fibers exhibit significantly higher gain for one linear polarization state than for the orthogonal state. Such a fiber can be used to construct a single-polarization fiber laser, amplifier, or amplified-spontaneous-emission (ASE) source without the need for additional optical components to obtain stable, linearly polarized operation.

  10. Development of a HgCdTe photomixer and impedance matched GaAs FET amplifier

    NASA Technical Reports Server (NTRS)

    Shanley, J. F.; Paulauskas, W. A.; Taylor, D. R.

    1982-01-01

    A research program for the development of a 10.6 micron HgCdTe photodiode/GaAs field effect transistor amplifier package for use at cryogenic temperatures (77k). The photodiode/amplifier module achieved a noise equivalent power per unit bandwidth of 5.7 times 10 to the 20th power W/Hz at 2.0 GHz. The heterodyne sensitivity of the HgCdTe photodiode was improved by designing and building a low noise GaAs field effect transistor amplifier operating at 77K. The Johnson noise of the amplifier was reduced at 77K, and thus resulted in an increased photodiode heterodyne sensitivity.

  11. X-band inverse class-F GaN internally-matched power amplifier

    NASA Astrophysics Data System (ADS)

    Zhao, Bo-Chao; Lu, Yang; Han, Wen-Zhe; Zheng, Jia-Xin; Zhang, Heng-Shuang; Ma, Pei-jun; Ma, Xiao-Hua; Hao, Yue

    2016-09-01

    An X-band inverse class-F power amplifier is realized by a 1-mm AlGaN/GaN high electron mobility transistor (HEMT). The intrinsic and parasitic components inside the transistor, especially output capacitor Cds, influence the harmonic impedance heavily at the X-band, so compensation design is used for meeting the harmonic condition of inverse class-F on the current source plane. Experiment results show that, in the continuous-wave mode, the power amplifier achieves 61.7% power added efficiency (PAE), which is 16.3% higher than the class-AB power amplifier realized by the same kind of HEMT. To the best of our knowledge, this is the first inverse class-F GaN internally-matched power amplifier, and the PAE is quite high at the X-band. Project supported by the National High Technology Research and Development Program of China (Grant No. 2015AA016801).

  12. Interpreting Transistor Noise

    NASA Astrophysics Data System (ADS)

    Pospieszalski, M. W.

    2010-10-01

    The simple noise models of field effect and bipolar transistors reviewed in this article are quite useful in engineering practice, as illustrated by measured and modeled results. The exact and approximate expressions for the noise parameters of FETs and bipolar transistors reveal certain common noise properties and some general noise properties of both devices. The usefulness of these expressions in interpreting the dependence of measured noise parameters on frequency, bias, and temperature and, consequently, in checking of consistency of measured data has been demonstrated.

  13. DISTRIBUTED AMPLIFIER INCORPORATING FEEDBACK

    DOEpatents

    Bell, P.R. Jr.

    1958-10-21

    An improved distributed amplifier system employing feedback for stabilization is presented. In accordance with the disclosed invention, a signal to be amplified is applled to one end of a suitable terminated grid transmission line. At intervals along the transmission line, the signal is fed to stable, resistance-capacitance coupled amplifiers incorporating feedback loops therein. The output current from each amplifier is passed through an additional tube to minimize the electrostatic capacitance between the tube elements of the last stage of the amplifier, and fed to appropriate points on an output transmission line, similar to the grid line, but terminated at the opposite (input) end. The output taken from the unterminated end of the plate transmission line is proportional to the input voltage impressed upon the grid line.

  14. Digital automatic gain amplifier

    NASA Technical Reports Server (NTRS)

    Holley, L. D.; Ward, J. O. (Inventor)

    1978-01-01

    A circuit is described for adjusting the amplitude of a reference signal to a predetermined level so as to permit subsequent data signals to be interpreted correctly. The circuit includes an operational amplifier having a feedback circuit connected between an output terminal and an input terminal; a bank of relays operably connected to a plurality of resistors; and a comparator comparing an output voltage of the amplifier with a reference voltage and generating a compared signal responsive thereto. Means is provided for selectively energizing the relays according to the compared signal from the comparator until the output signal from the amplifier equals to the reference signal. A second comparator is provided for comparing the output of the amplifier with a second voltage source so as to illuminate a lamp when the output signal from the amplifier exceeds the second voltage.

  15. VOLTAGE-CONTROLLED TRANSISTOR OSCILLATOR

    DOEpatents

    Scheele, P.F.

    1958-09-16

    This patent relates to transistor oscillators and in particular to those transistor oscillators whose frequencies vary according to controlling voltages. A principal feature of the disclosed transistor oscillator circuit resides in the temperature compensation of the frequency modulating stage by the use of a resistorthermistor network. The resistor-thermistor network components are selected to have the network resistance, which is in series with the modulator transistor emitter circuit, vary with temperature to compensate for variation in the parameters of the transistor due to temperature change.

  16. Accelerating the life of transistors

    NASA Astrophysics Data System (ADS)

    Haochun, Qi; Changzhi, Lü; Xiaoling, Zhang; Xuesong, Xie

    2013-06-01

    Choosing small and medium power switching transistors of the NPN type in a 3DK set as the study object, the test of accelerating life is conducted in constant temperature and humidity, and then the data are statistically analyzed with software developed by ourselves. According to degradations of such sensitive parameters as the reverse leakage current of transistors, the lifetime order of transistors is about more than 104 at 100 °C and 100% relative humidity (RH) conditions. By corrosion fracture of transistor outer leads and other failure modes, with the failure truncated testing, the average lifetime rank of transistors in different distributions is extrapolated about 103. Failure mechanism analyses of degradation of electrical parameters, outer lead fracture and other reasons that affect transistor lifetime are conducted. The findings show that the impact of external stress of outer leads on transistor reliability is more serious than that of parameter degradation.

  17. Tuning Broadband Microwave Amplifiers

    SciTech Connect

    Alaniz, Gabriel

    2003-09-05

    The PEP-II/DA {Phi} NE/ALS longitudinal feedback systems are complex wide bandwidth systems requiring analog, digital and microwave circuits. The solid-state amplifier is one of the components in the microwave circuit that is required to suppress the coupled bunch instabilities that exist in the PEP-II accelerator. The suppression is achieved by using an antenna as a kicker structure that provides an electric field in order to increase or decrease the energy of particles passing through the structure. The amplifier is made up of sixteen 30 to 35W microstrip GaAs FET modules that are combined to obtain 500W over a bandwidth of 850MHz to 1850MHz. The amplifier malfunctioned causing a reduction in the functionality and power output of the individual GaAs FET modules. The amplifier must be repaired. After repair, the amplifier must be tuned to optimize the gain while maintaining proper power output. The amplifier is tuned using microstrip circuit techniques. A variety of microstrip methods are used to obtain the proper line impedance. The result is a working amplifier that operates efficiently.

  18. Universal signal conditioning amplifier

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J.; Hallberg, Carl; Cecil, Jim

    1994-01-01

    A state-of-the-art instrumentation amplifier capable of being used with most types of transducers has been developed at the Kennedy Space Center. This Universal Signal Conditioning Amplifier (USCA) can eliminate costly measurement setup item and troubleshooting, improve system reliability and provide more accurate data than conventional amplifiers. The USCA can configure itself for maximum resolution and accuracy based on information read from a RAM chip attached to each transducer. Excitation voltages or current are also automatically configured. The amplifier uses both analog and digital state-of-the-art technology with analog-to-digital conversion performed in the early stages in order to minimize errors introduced by offset and gain drifts in the analog components. A dynamic temperature compensation scheme has been designed to achieve and maintain 12-bit accuracy of the amplifier from 0 to 70 C. The digital signal processing section allows the implementation of digital filters up to 511th order. The amplifier can also perform real-time linearizations up to fourth order while processing data at a rate of 23.438 kS/s. Both digital and analog outputs are available from the amplifier.

  19. Multimode Silicon Nanowire Transistors

    PubMed Central

    2014-01-01

    The combined capabilities of both a nonplanar design and nonconventional carrier injection mechanisms are subject to recent scientific investigations to overcome the limitations of silicon metal oxide semiconductor field effect transistors. In this Letter, we present a multimode field effect transistors device using silicon nanowires that feature an axial n-type/intrinsic doping junction. A heterostructural device design is achieved by employing a self-aligned nickel-silicide source contact. The polymorph operation of the dual-gate device enabling the configuration of one p- and two n-type transistor modes is demonstrated. Not only the type but also the carrier injection mode can be altered by appropriate biasing of the two gate terminals or by inverting the drain bias. With a combined band-to-band and Schottky tunneling mechanism, in p-type mode a subthreshold swing as low as 143 mV/dec and an ON/OFF ratio of up to 104 is found. As the device operates in forward bias, a nonconventional tunneling transistor is realized, enabling an effective suppression of ambipolarity. Depending on the drain bias, two different n-type modes are distinguishable. The carrier injection is dominated by thermionic emission in forward bias with a maximum ON/OFF ratio of up to 107 whereas in reverse bias a Schottky tunneling mechanism dominates the carrier transport. PMID:25303290

  20. Towards the ultimate transistor

    NASA Astrophysics Data System (ADS)

    Natelson, Douglas

    2009-06-01

    The first transistor, made more than 60 years ago at Bell Labs, was a couple of inches across. Today, a typical laptop computer uses a processor chip that contains well over a billion transistors, each one with electrodes separated by less than 50 nm of silicon, which is less than a thousandth of the diameter of a human hair. This continual drive for miniaturization, with the density of transistors doubling roughly every two years, was first noted by Intel co-founder Gordon Moore in 1965, and has been such a mainstay of electronics development that it is now enshrined as "Moore's law". These billions of transistors are made by "top down" methods that involve depositing thin layers of materials, patterning nano-scale stencils and effectively carving away the unwanted bits. The incredible success of this approach is almost impossible to overstate. The end result is billions of individual components on a single chip, essentially all working perfectly and continuously for years on end. No other manufactured technology comes remotely close in reliability or cost-per-widget.

  1. Multimode silicon nanowire transistors.

    PubMed

    Glassner, Sebastian; Zeiner, Clemens; Periwal, Priyanka; Baron, Thierry; Bertagnolli, Emmerich; Lugstein, Alois

    2014-11-12

    The combined capabilities of both a nonplanar design and nonconventional carrier injection mechanisms are subject to recent scientific investigations to overcome the limitations of silicon metal oxide semiconductor field effect transistors. In this Letter, we present a multimode field effect transistors device using silicon nanowires that feature an axial n-type/intrinsic doping junction. A heterostructural device design is achieved by employing a self-aligned nickel-silicide source contact. The polymorph operation of the dual-gate device enabling the configuration of one p- and two n-type transistor modes is demonstrated. Not only the type but also the carrier injection mode can be altered by appropriate biasing of the two gate terminals or by inverting the drain bias. With a combined band-to-band and Schottky tunneling mechanism, in p-type mode a subthreshold swing as low as 143 mV/dec and an ON/OFF ratio of up to 10(4) is found. As the device operates in forward bias, a nonconventional tunneling transistor is realized, enabling an effective suppression of ambipolarity. Depending on the drain bias, two different n-type modes are distinguishable. The carrier injection is dominated by thermionic emission in forward bias with a maximum ON/OFF ratio of up to 10(7) whereas in reverse bias a Schottky tunneling mechanism dominates the carrier transport. PMID:25303290

  2. Radiation-hardened transistor and integrated circuit

    DOEpatents

    Ma, Kwok K.

    2007-11-20

    A composite transistor is disclosed for use in radiation hardening a CMOS IC formed on an SOI or bulk semiconductor substrate. The composite transistor has a circuit transistor and a blocking transistor connected in series with a common gate connection. A body terminal of the blocking transistor is connected only to a source terminal thereof, and to no other connection point. The blocking transistor acts to prevent a single-event transient (SET) occurring in the circuit transistor from being coupled outside the composite transistor. Similarly, when a SET occurs in the blocking transistor, the circuit transistor prevents the SET from being coupled outside the composite transistor. N-type and P-type composite transistors can be used for each and every transistor in the CMOS IC to radiation harden the IC, and can be used to form inverters and transmission gates which are the building blocks of CMOS ICs.

  3. Low-Noise MMIC Amplifiers for 120 to 180 GHz

    NASA Technical Reports Server (NTRS)

    Pukala, David; Samoska, Lorene; Peralta, Alejandro; Bayuk, Brian; Grundbacher, Ron; Oliver, Patricia; Cavus, Abdullah; Liu, Po-Hsin

    2009-01-01

    Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype low-noise amplifiers (LNAs) to be incorporated into instruments for sensing cosmic microwave background radiation. There are also potential uses for such LNAs in electronic test equipment, passive millimeter- wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The main advantage afforded by these MMIC LNAs, relative to prior MMIC LNAs, is that their coverage of the 120-to-180-GHz frequency band makes them suitable for reuse in a wider variety of applications without need to redesign them. Each of these MMIC amplifiers includes InP transistors and coplanar waveguide circuitry on a 50- mthick chip (see Figure 1). Coplanar waveguide transmission lines are used for both applying DC bias and matching of input and output impedances of each transistor stage. Via holes are incorporated between top and bottom ground planes to suppress propagation of electromagnetic modes in the substrate. On the basis of computational simulations, each of these amplifiers was expected to operate with a small-signal gain of 14 dB and a noise figure of 4.3 dB. At the time of writing this article, measurements of noise figures had not been reported, but on-chip measurements had shown gains approaching their simulated values (see Figure 2).

  4. Multipass optical parametric amplifier

    SciTech Connect

    Jeys, T.H.

    1996-08-01

    A compact, low-threshold, multipass optical parametric amplifier has been developed for the conversion of short-pulse (360-ps) 1064-nm Nd:YAG laser radiation into eye-safe 1572-nm radiation for laser ranging and radar applications. The amplifier had a threshold pump power of as low as 45{mu}J, and at three to four times this threshold pump power the amplifier converted 30{percent} of the input 1064-nm radiation into 1572-nm output radiation. {copyright} {ital 1996 Optical Society of America.}

  5. Fully relayed regenerative amplifier

    DOEpatents

    Glass, Alexander J.

    1981-01-01

    A regenerative laser apparatus and method using the optical relay concept to maintain high fill factors, to suppress diffraction effects, and to minimize phase distortions in a regenerative amplifier.

  6. Broadband linear high-voltage amplifier for radio frequency ion traps.

    PubMed

    Kuhlicke, Alexander; Palis, Klaus; Benson, Oliver

    2014-11-01

    We developed a linear high-voltage amplifier for small capacitive loads consisting of a high-voltage power supply and a transistor amplifier. With this cost-effective circuit including only standard parts sinusoidal signals with a few volts can be amplified to 1.7 kVpp over a usable frequency range at large-signal response spanning four orders of magnitude from 20 Hz to 100 kHz under a load of 10 pF. For smaller output voltages the maximum frequency shifts up to megahertz. We test different capacitive loads to probe the influence on the performance. The presented amplifier is sustained short-circuit proof on the output side, which is a significant advantage over other amplifier concepts. The amplifier can be used to drive radio frequency ion traps for single charged nano- and microparticles, which will be presented in brief.

  7. Broadband Characterization of a 100 to 180 GHz Amplifier

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka; Deal, W. R.; Mei, X. B.; Lai, R.

    2007-01-01

    Atmospheric science and weather forecasting require measurements of the temperature and humidity vs. altitude. These sounding measurements are obtained at frequencies close to the resonance frequencies of oxygen (118 GHz) and water (183 GHz) molecules. We have characterized a broadband amplifier that will increase the sensitivity of sounding and other instruments at these frequencies. This study demonstrated for the first t1me continuous low noise amplification from 100 to 180 GHz. The measured InP monolithic millimeter-wave Integrated circuit (MMIC) amplifier had more than 18 dB of gain from 100 to 180 GHz and 15 dB of gain up to 220 GHz. This is the widest bandwidth low noise amplifier result at these frequencies to date. The circuit was fabricated in Northrop Grumman Corporation 35 nm InP high electron mobility transistor (HEMT).

  8. HEMT Amplifiers and Equipment for their On-Wafer Testing

    NASA Technical Reports Server (NTRS)

    Fung, King man; Gaier, Todd; Samoska, Lorene; Deal, William; Radisic, Vesna; Mei, Xiaobing; Lai, Richard

    2008-01-01

    Power amplifiers comprising InP-based high-electron-mobility transistors (HEMTs) in coplanar-waveguide (CPW) circuits designed for operation at frequencies of hundreds of gigahertz, and a test set for onwafer measurement of their power levels have been developed. These amplifiers utilize an advanced 35-nm HEMT monolithic microwave integrated-circuit (MMIC) technology and have potential utility as local-oscillator drivers and power sources in future submillimeter-wavelength heterodyne receivers and imaging systems. The test set can reduce development time by enabling rapid output power characterization, not only of these and similar amplifiers, but also of other coplanar-waveguide power circuits, without the necessity of packaging the circuits.

  9. Linear-log counting-rate meter uses transconductance characteristics of a silicon planar transistor

    NASA Technical Reports Server (NTRS)

    Eichholz, J. J.

    1969-01-01

    Counting rate meter compresses a wide range of data values, or decades of current. Silicon planar transistor, operating in the zero collector-base voltage mode, is used as a feedback element in an operational amplifier to obtain the log response.

  10. Radio frequency analog electronics based on carbon nanotube transistors

    PubMed Central

    Kocabas, Coskun; Kim, Hoon-sik; Banks, Tony; Rogers, John A.; Pesetski, Aaron A.; Baumgardner, James E.; Krishnaswamy, S. V.; Zhang, Hong

    2008-01-01

    The potential to exploit single-walled carbon nanotubes (SWNTs) in advanced electronics represents a continuing, major source of interest in these materials. However, scalable integration of SWNTs into circuits is challenging because of difficulties in controlling the geometries, spatial positions, and electronic properties of individual tubes. We have implemented solutions to some of these challenges to yield radio frequency (RF) SWNT analog electronic devices, such as narrow band amplifiers operating in the VHF frequency band with power gains as high as 14 dB. As a demonstration, we fabricated nanotube transistor radios, in which SWNT devices provide all of the key functions, including resonant antennas, fixed RF amplifiers, RF mixers, and audio amplifiers. These results represent important first steps to practical implementation of SWNTs in high-speed analog circuits. Comparison studies indicate certain performance advantages over silicon and capabilities that complement those in existing compound semiconductor technologies. PMID:18227509

  11. Improved chopper circuit uses parallel transistors

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Parallel transistor chopper circuit operates with one transistor in the forward mode and the other in the inverse mode. By using this method, it acts as a single, symmetrical, bidirectional transistor, and reduces and stabilizes the offset voltage.

  12. Transistor voltage comparator performs own sensing

    NASA Technical Reports Server (NTRS)

    Cliff, R. A.

    1965-01-01

    Detection of the highest voltage input among a group of varying voltage inputs is accomplished by a transistorized voltage comparison circuit. The collector circuits of the transistors perform the sensing function. Input voltage levels are governed by the transistors.

  13. High Efficiency Microwave Power Amplifier: From the Lab to Industry

    NASA Technical Reports Server (NTRS)

    Sims, William Herbert, III; Bell, Joseph L. (Technical Monitor)

    2001-01-01

    Since the beginnings of space travel, various microwave power amplifier designs have been employed. These included Class-A, -B, and -C bias arrangements. However, shared limitation of these topologies is the inherent high total consumption of input power associated with the generation of radio frequency (RF)/microwave power. The power amplifier has always been the largest drain for the limited available power on the spacecraft. Typically, the conversion efficiency of a microwave power amplifier is 10 to 20%. For a typical microwave power amplifier of 20 watts, input DC power of at least 100 watts is required. Such a large demand for input power suggests that a better method of RF/microwave power generation is required. The price paid for using a linear amplifier where high linearity is unnecessary includes higher initial and operating costs, lower DC-to-RF conversion efficiency, high power consumption, higher power dissipation and the accompanying need for higher capacity heat removal means, and an amplifier that is more prone to parasitic oscillation. The first use of a higher efficiency mode of power generation was described by Baxandall in 1959. This higher efficiency mode, Class-D, is achieved through distinct switching techniques to reduce the power losses associated with switching, conduction, and gate drive losses of a given transistor.

  14. Some characteristic features of the construction of the amplifying channel for working with semiconductor detectors in the charged particle energy spectrometer. [noise minimization at preamplifier input

    NASA Technical Reports Server (NTRS)

    Kuzyuta, E. I.

    1974-01-01

    A transistorized spectrometric amplifier with a shaper is reported that selects the shape of the frequency characteristic of the amplifying channel for which the primary frequency spectrum of the signal will pass, but where the noise spectrum is limited to the maximum. A procedure is presented for selecting the shaping circuits and their inclusion principles.

  15. TRANSISTOR HIGH VOLTAGE POWER SUPPLY

    DOEpatents

    Driver, G.E.

    1958-07-15

    High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

  16. High voltage power transistor development

    NASA Technical Reports Server (NTRS)

    Hower, P. L.

    1981-01-01

    Design considerations, fabrication procedures, and methods of evaluation for high-voltage power-transistor development are discussed. Technique improvements such as controlling the electric field at the surface and perserving lifetimes in the collector region which have advanced the state of the art in high-voltage transistors are discussed. These improvements can be applied directly to the development of 1200 volt, 200 ampere transistors.

  17. Polarization induced doped transistor

    DOEpatents

    Xing, Huili; Jena, Debdeep; Nomoto, Kazuki; Song, Bo; Zhu, Mingda; Hu, Zongyang

    2016-06-07

    A nitride-based field effect transistor (FET) comprises a compositionally graded and polarization induced doped p-layer underlying at least one gate contact and a compositionally graded and doped n-channel underlying a source contact. The n-channel is converted from the p-layer to the n-channel by ion implantation, a buffer underlies the doped p-layer and the n-channel, and a drain underlies the buffer.

  18. Design of Wireless Power Transfer System Using E-class Amplifier

    NASA Astrophysics Data System (ADS)

    Zhang, Le; Zhang, Yuan; Zhu, Wu; Huang, Jing

    2016-05-01

    This paper mainly discuss the wireless power transfer system based on class-E amplifier. Firstly, the system coupling model was established and the working principle and parameter design of class-E amplifier was analyzed in detail. Then proposed a method of high frequency driver design using high frequency power transistor push-pull mode. On this basis, we successfully designed and built the wireless power transfer system. The maximum transmission power is 15W and the transmission distance is 20cm. The method of class-E amplifier is verified in wireless power transfer system.

  19. SEMICONDUCTOR DEVICES Effect of collector bias current on the linearity of common-emitter BJT amplifiers

    NASA Astrophysics Data System (ADS)

    Kun, Li; Jianfu, Teng; Xiuwei, Xuan

    2010-12-01

    Using a Volterra series, an explicit formula is derived for the connection between input 3rd-order intercept point and collector bias current (ICQ) in a common-emitter bipolar junction transistor amplifier. The analysis indicates that the larger ICQ is, the more linear the amplifier is. Furthermore, this has been verified by experiment. This study also integrates a method called dynamic bias current for expanding the dynamic range of an LNA (low noise amplifier) as an application of the analysis result obtained above. IMR3 (3rd-order intermodulation rate) is applied to evaluate the LNA's performance with and without adopting this method in this study.

  20. Electrospun amplified fiber optics.

    PubMed

    Morello, Giovanni; Camposeo, Andrea; Moffa, Maria; Pisignano, Dario

    2015-03-11

    All-optical signal processing is the focus of much research aiming to obtain effective alternatives to existing data transmission platforms. Amplification of light in fiber optics, such as in Erbium-doped fiber amplifiers, is especially important for efficient signal transmission. However, the complex fabrication methods involving high-temperature processes performed in a highly pure environment slow the fabrication process and make amplified components expensive with respect to an ideal, high-throughput, room temperature production. Here, we report on near-infrared polymer fiber amplifiers working over a band of ∼20 nm. The fibers are cheap, spun with a process entirely carried out at room temperature, and shown to have amplified spontaneous emission with good gain coefficients and low levels of optical losses (a few cm(-1)). The amplification process is favored by high fiber quality and low self-absorption. The found performance metrics appear to be suitable for short-distance operations, and the large variety of commercially available doping dyes might allow for effective multiwavelength operations by electrospun amplified fiber optics.

  1. Electrospun Amplified Fiber Optics

    PubMed Central

    2015-01-01

    All-optical signal processing is the focus of much research aiming to obtain effective alternatives to existing data transmission platforms. Amplification of light in fiber optics, such as in Erbium-doped fiber amplifiers, is especially important for efficient signal transmission. However, the complex fabrication methods involving high-temperature processes performed in a highly pure environment slow the fabrication process and make amplified components expensive with respect to an ideal, high-throughput, room temperature production. Here, we report on near-infrared polymer fiber amplifiers working over a band of ∼20 nm. The fibers are cheap, spun with a process entirely carried out at room temperature, and shown to have amplified spontaneous emission with good gain coefficients and low levels of optical losses (a few cm–1). The amplification process is favored by high fiber quality and low self-absorption. The found performance metrics appear to be suitable for short-distance operations, and the large variety of commercially available doping dyes might allow for effective multiwavelength operations by electrospun amplified fiber optics. PMID:25710188

  2. Laser amplifier and method

    DOEpatents

    Backus, S.; Kapteyn, H.C.; Murnane, M.M.

    1997-07-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethrough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate. 7 figs.

  3. Laser amplifier and method

    DOEpatents

    Backus, Sterling; Kapteyn, Henry C.; Murnane, Margaret M.

    1997-01-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate.

  4. Analogy of transistor function with modulating photonic band gap in electromagnetically induced grating.

    PubMed

    Wang, Zhiguo; Ullah, Zakir; Gao, Mengqin; Zhang, Dan; Zhang, Yiqi; Gao, Hong; Zhang, Yanpeng

    2015-09-09

    Optical transistor is a device used to amplify and switch optical signals. Many researchers focus on replacing current computer components with optical equivalents, resulting in an optical digital computer system processing binary data. Electronic transistor is the fundamental building block of modern electronic devices. To replace electronic components with optical ones, an equivalent optical transistor is required. Here we compare the behavior of an optical transistor with the reflection from a photonic band gap structure in an electromagnetically induced transparency medium. A control signal is used to modulate the photonic band gap structure. Power variation of the control signal is used to provide an analogy between the reflection behavior caused by modulating the photonic band gap structure and the shifting of Q-point (Operation point) as well as amplification function of optical transistor. By means of the control signal, the switching function of optical transistor has also been realized. Such experimental schemes could have potential applications in making optical diode and optical transistor used in quantum information processing.

  5. A steep-slope transistor based on abrupt electronic phase transition.

    PubMed

    Shukla, Nikhil; Thathachary, Arun V; Agrawal, Ashish; Paik, Hanjong; Aziz, Ahmedullah; Schlom, Darrell G; Gupta, Sumeet Kumar; Engel-Herbert, Roman; Datta, Suman

    2015-08-07

    Collective interactions in functional materials can enable novel macroscopic properties like insulator-to-metal transitions. While implementing such materials into field-effect-transistor technology can potentially augment current state-of-the-art devices by providing unique routes to overcome their conventional limits, attempts to harness the insulator-to-metal transition for high-performance transistors have experienced little success. Here, we demonstrate a pathway for harnessing the abrupt resistivity transformation across the insulator-to-metal transition in vanadium dioxide (VO2), to design a hybrid-phase-transition field-effect transistor that exhibits gate controlled steep ('sub-kT/q') and reversible switching at room temperature. The transistor design, wherein VO2 is implemented in series with the field-effect transistor's source rather than into the channel, exploits negative differential resistance induced across the VO2 to create an internal amplifier that facilitates enhanced performance over a conventional field-effect transistor. Our approach enables low-voltage complementary n-type and p-type transistor operation as demonstrated here, and is applicable to other insulator-to-metal transition materials, offering tantalizing possibilities for energy-efficient logic and memory applications.

  6. Analogy of transistor function with modulating photonic band gap in electromagnetically induced grating

    NASA Astrophysics Data System (ADS)

    Wang, Zhiguo; Ullah, Zakir; Gao, Mengqin; Zhang, Dan; Zhang, Yiqi; Gao, Hong; Zhang, Yanpeng

    2015-09-01

    Optical transistor is a device used to amplify and switch optical signals. Many researchers focus on replacing current computer components with optical equivalents, resulting in an optical digital computer system processing binary data. Electronic transistor is the fundamental building block of modern electronic devices. To replace electronic components with optical ones, an equivalent optical transistor is required. Here we compare the behavior of an optical transistor with the reflection from a photonic band gap structure in an electromagnetically induced transparency medium. A control signal is used to modulate the photonic band gap structure. Power variation of the control signal is used to provide an analogy between the reflection behavior caused by modulating the photonic band gap structure and the shifting of Q-point (Operation point) as well as amplification function of optical transistor. By means of the control signal, the switching function of optical transistor has also been realized. Such experimental schemes could have potential applications in making optical diode and optical transistor used in quantum information processing.

  7. Analogy of transistor function with modulating photonic band gap in electromagnetically induced grating

    PubMed Central

    Wang, Zhiguo; Ullah, Zakir; Gao, Mengqin; Zhang, Dan; Zhang, Yiqi; Gao, Hong; Zhang, Yanpeng

    2015-01-01

    Optical transistor is a device used to amplify and switch optical signals. Many researchers focus on replacing current computer components with optical equivalents, resulting in an optical digital computer system processing binary data. Electronic transistor is the fundamental building block of modern electronic devices. To replace electronic components with optical ones, an equivalent optical transistor is required. Here we compare the behavior of an optical transistor with the reflection from a photonic band gap structure in an electromagnetically induced transparency medium. A control signal is used to modulate the photonic band gap structure. Power variation of the control signal is used to provide an analogy between the reflection behavior caused by modulating the photonic band gap structure and the shifting of Q-point (Operation point) as well as amplification function of optical transistor. By means of the control signal, the switching function of optical transistor has also been realized. Such experimental schemes could have potential applications in making optical diode and optical transistor used in quantum information processing. PMID:26349444

  8. A steep-slope transistor based on abrupt electronic phase transition

    PubMed Central

    Shukla, Nikhil; Thathachary, Arun V.; Agrawal, Ashish; Paik, Hanjong; Aziz, Ahmedullah; Schlom, Darrell G.; Gupta, Sumeet Kumar; Engel-Herbert, Roman; Datta, Suman

    2015-01-01

    Collective interactions in functional materials can enable novel macroscopic properties like insulator-to-metal transitions. While implementing such materials into field-effect-transistor technology can potentially augment current state-of-the-art devices by providing unique routes to overcome their conventional limits, attempts to harness the insulator-to-metal transition for high-performance transistors have experienced little success. Here, we demonstrate a pathway for harnessing the abrupt resistivity transformation across the insulator-to-metal transition in vanadium dioxide (VO2), to design a hybrid-phase-transition field-effect transistor that exhibits gate controlled steep (‘sub-kT/q') and reversible switching at room temperature. The transistor design, wherein VO2 is implemented in series with the field-effect transistor's source rather than into the channel, exploits negative differential resistance induced across the VO2 to create an internal amplifier that facilitates enhanced performance over a conventional field-effect transistor. Our approach enables low-voltage complementary n-type and p-type transistor operation as demonstrated here, and is applicable to other insulator-to-metal transition materials, offering tantalizing possibilities for energy-efficient logic and memory applications. PMID:26249212

  9. STABILIZED FEEDBACK AMPLIFIER

    DOEpatents

    Fishbine, H.L.; Sewell, C. Jr.

    1957-08-01

    Negative feedback amplifiers, and particularly a negative feedback circuit which is economical on amode power consumption, are described. Basically, the disclosed circuit comprises two tetrode tubes where the output of the first tube is capacitamce coupled to the grid of the second tube, which in turn has its plate coupled to the cathode of the first tube to form a degenerative feedback circuit. Operating potential for screen of the second tube is supplied by connecting the cathode resistor of the first tube to the screen, while the screen is by-passed to the cathode of its tube for the amplified frequencies. Also, the amplifier incorporates a circuit to stabilize the transconductance of the tubes by making the grid potential of each tube interdependent on anode currents of both lubes by voltage divider circuitry.

  10. NASA satellite communications application research, phase 2 addendum. Efficient high power, solid state amplifier for EHF communications

    NASA Technical Reports Server (NTRS)

    Benet, James

    1994-01-01

    This document is an addendum to the NASA Satellite Communications Application Research (SCAR) Phase 2 Final Report, 'Efficient High Power, Solid State Amplifier for EHF Communications.' This report describes the work performed from 1 August 1993 to 11 March 1994, under contract number NASW-4513. During this reporting period an array of transistor amplifiers was repaired by replacing all MMIC amplifier chips. The amplifier array was then tested using three different feedhorn configurations. Descriptions, procedures, and results of this testing are presented in this report, and conclusions are drawn based on the test results obtained.

  11. Measuring bi-directional current through a field-effect transistor by virtue of drain-to-source voltage measurement

    DOEpatents

    Turner, Steven Richard

    2006-12-26

    A method and apparatus for measuring current, and particularly bi-directional current, in a field-effect transistor (FET) using drain-to-source voltage measurements. The drain-to-source voltage of the FET is measured and amplified. This signal is then compensated for variations in the temperature of the FET, which affects the impedance of the FET when it is switched on. The output is a signal representative of the direction of the flow of current through the field-effect transistor and the level of the current through the field-effect transistor. Preferably, the measurement only occurs when the FET is switched on.

  12. Spatial Light Amplifier Modulators

    NASA Technical Reports Server (NTRS)

    Eng, Sverre T.; Olsson, N. Anders

    1992-01-01

    Spatial light amplifier modulators (SLAM's) are conceptual devices that effect two-dimensional spatial modulation in optical computing and communication systems. Unlike current spatial light modulators, these provide gain. Optical processors incorporating SLAM's designed to operate in reflection or transmission mode. Each element of planar SLAM array is optical amplifier - surface-emitting diode laser. Array addressed electrically with ac modulating signals superimposed on dc bias currents supplied to lasers. SLAM device provides both desired modulation and enough optical gain to enable splitting of output signal into many optical fibers without excessive loss of power.

  13. A grid amplifier

    NASA Technical Reports Server (NTRS)

    Kim, Moonil; Weikle, Robert M., II; Hacker, Jonathan B.; Delisio, Michael P.; Rutledge, David B.; Rosenberg, James J.; Smith, R. P.

    1991-01-01

    A 50-MESFET grid amplifier is reported that has a gain of 11 dB at 3.3 GHz. The grid isolates the input from the output by using vertical polarization for the input beam and horizontal polarization for the transmitted output beam. The grid unit cell is a two-MESFET differential amplifier. A simple calibration procedure allows the gain to be calculated from a relative power measurement. This grid is a hybrid circuit, but the structure is suitable for fabrication as a monolithic wafer-scale integrated circuit, particularly at millimeter wavelengths.

  14. Universal signal conditioning amplifier

    NASA Technical Reports Server (NTRS)

    Larson, William E.; Hallberg, Carl; Medelius, Pedro J.

    1994-01-01

    Engineers at NASA's Kennedy Space Center have designed a signal conditioning amplifier which automatically matches itself to almost any kind of transducer. The product, called Universal Signal Conditioning Amplifier (USCA), uses state-of-the-art technologies to deliver high accuracy measurements. USCA's features which can be either programmable or automated include: voltage, current, or pulsed excitation, unlimited resolution gain, digital filtering and both analog and digital output. USCA will be used at Kennedy Space Center's launch pads for environmental measurements such as vibrations, strains, temperatures and overpressures. USCA is presently being commercialized through a co-funded agreement between NASA, the State of Florida, and Loral Test and Information Systems, Inc.

  15. Submillimeter-Wave Amplifier Module with Integrated Waveguide Transitions

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Chattopadhyay, Goutam; Pukala, David; Gaier, Todd; Soria, Mary; ManFung, King; Deal, William; Mei, Gerry; Radisic, Vesna; Lai, Richard

    2009-01-01

    To increase the usefulness of monolithic millimeter-wave integrated circuit (MMIC) components at submillimeter-wave frequencies, a chip has been designed that incorporates two integrated, radial E-plane probes with an MMIC amplifier in between, thus creating a fully integrated waveguide module. The integrated amplifier chip has been fabricated in 35-nm gate length InP high-electron-mobility-transistor (HEMT) technology. The radial probes were mated to grounded coplanar waveguide input and output lines in the internal amplifier. The total length of the internal HEMT amplifier is 550 m, while the total integrated chip length is 1,085 m. The chip thickness is 50 m with the chip width being 320 m. The internal MMIC amplifier is biased through wire-bond connections to the gates and drains of the chip. The chip has 3 stages, employing 35-nm gate length transistors in each stage. Wire bonds from the DC drain and gate pads are connected to off-chip shunt 51-pF capacitors, and additional off-chip capacitors and resistors are added to the gate and drain bias lines for low-frequency stability of the amplifier. Additionally, bond wires to the grounded coplanar waveguide pads at the RF input and output of the internal amplifier are added to ensure good ground connections to the waveguide package. The S-parameters of the module, not corrected for input or output waveguide loss, are measured at the waveguide flange edges. The amplifier module has over 10 dB of gain from 290 to 330 GHz, with a peak gain of over 14 dB at 307 GHz. The WR2.2 waveguide cutoff is again observed at 268 GHz. The module is biased at a drain current of 27 mA, a drain voltage of 1.24 V, and a gate voltage of +0.21 V. Return loss of the module is very good between 5 to 25 dB. This result illustrates the usefulness of the integrated radial probe transition, and the wide (over 10-percent) bandwidth that one can expect for amplifier modules with integrated radial probes in the submillimeter-regime (>300 GHz).

  16. Fourier plane image amplifier

    DOEpatents

    Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.

    1995-12-12

    A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.

  17. Fourier plane image amplifier

    DOEpatents

    Hackel, Lloyd A.; Hermann, Mark R.; Dane, C. Brent; Tiszauer, Detlev H.

    1995-01-01

    A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.

  18. A high efficiency C-band internally-matched harmonic tuning GaN power amplifier

    NASA Astrophysics Data System (ADS)

    Lu, Y.; Zhao, B. C.; Zheng, J. X.; Zhang, H. S.; Zheng, X. F.; Ma, X. H.; Hao, Y.; Ma, P. J.

    2016-09-01

    In this paper, a high efficiency C-band gallium nitride (GaN) internally-matched power amplifier (PA) is presented. This amplifier consists of 2-chips of self-developed GaN high-electron mobility transistors (HEMTs) with 16 mm total gate width on SiC substrate. New harmonic manipulation circuits are induced both in the input and output matching networks for high efficiency matching at fundamental and 2nd-harmonic frequency, respectively. The developed amplifier has achieved 72.1% power added efficiency (PAE) with 107.4 W output power at 5 GHz. To the best of our knowledge, this amplifier exhibits the highest PAE in C-band GaN HEMT amplifiers with over 100 W output power. Additionally, 1000 hours' aging test reveals high reliability for practical applications.

  19. Power transistor switching characterization

    NASA Technical Reports Server (NTRS)

    Blackburn, D. L.

    1981-01-01

    The switching properties of power transistors are investigated. The devices studied were housed in IO-3 cases and were of an n(+)-p-n(-)-n(+) vertical dopant structure. The effects of the magnitude of the reverse-base current and temperature on the reverse-bias second breakdown characteristics are discussed. Brief discussions of device degradation due to second breakdown and of a constant voltage turn-off circuit are included. A description of a vacuum tube voltage clamp circuit which reduces clamped collector voltage overshoot is given.

  20. A fully integrated neural recording amplifier with DC input stabilization.

    PubMed

    Mohseni, Pedram; Najafi, Khalil

    2004-05-01

    This paper presents a low-power low-noise fully integrated bandpass operational amplifier for a variety of biomedical neural recording applications. A standard two-stage CMOS amplifier in a closed-loop resistive feedback configuration provides a stable ac gain of 39.3 dB at 1 kHz. A subthreshold PMOS input transistor is utilized to clamp the large and random dc open circuit potentials that normally exist at the electrode-electrolyte interface. The low cutoff frequency of the amplifier is programmable up to 50 Hz, while its high cutoff frequency is measured to be 9.1 kHz. The tolerable dc input range is measured to be at least +/- 0.25 V with a dc rejection factor of at least 29 dB. The amplifier occupies 0.107 mm2 in die area, and dissipates 115 microW from a 3 V power supply. The total measured input-referred noise voltage in the frequency range of 0.1-10 kHz is 7.8 microVrms. It is fabricated using AMI 1.5 microm double-poly double-metal n-well CMOS process. This paper presents full characterization of the dc, ac, and noise performance of this amplifier through in vitro measurements in saline using two different neural recording electrodes. PMID:15132510

  1. V-band monolithic two stage HEMT amplifiers

    NASA Astrophysics Data System (ADS)

    Aust, M.; Yonaki, J.; Nakano, K.; Berenz, J.; Dow, G.

    Two different types of HEMT (high-electron-mobility transistor) monolithic low-noise amplifiers (LNAs) using AlGaAs/GaAs and pseudomorphic InGaAs/GaAs materials have been developed and have demonstrated excellent performance at 60 GHz. These monolithic LNAs have achieved noise figures of 5 dB, as well as associated gains of 11 dB. These two-stage circuits both utilize 0.2- x 60-micron HEMT devices for both bandpass and low-pass circuit topologies. Noise figures as low as 4.5 dB have been observed for single-stage MMIC- (monolithic-microwave-integrated-circuit) implemented LNAs, and gains in excess of 20 dB have been observed for three-stage versions of this amplifier with a 5-dB noise figure in the V band. This result represents the state-of-the art monolithic HEMT amplifier performance for AlGaAs and pseudomorphic InGaAs materials. This MMIC amplifier can occupy about less than one-third the size of existing MIC hybrid V-band LNAs. This represents a significant size reduction and cost saving due to repeatable circuit performance with monolithic technology. The chip sizes are both 1.6 x 2.7 mm for these two-stage amplifiers.

  2. Characterizing the Switching Thresholds of Magnetophoretic Transistors.

    PubMed

    Abedini-Nassab, Roozbeh; Joh, Daniel Y; Van Heest, Melissa A; Yi, John S; Baker, Cody; Taherifard, Zohreh; Margolis, David M; Garcia, J Victor; Chilkoti, Ashutosh; Murdoch, David M; Yellen, Benjamin B

    2015-10-28

    The switching thresholds of magnetophoretic transistors for sorting cells in microfluidic environments are characterized. The transistor operating conditions require short 20-30 mA pulses of electrical current. By demonstrating both attractive and repulsive transistor modes, a single transistor architecture is used to implement the full write cycle for importing and exporting single cells in specified array sites. PMID:26349853

  3. Ultrasensitive biomolecular assays with amplifying nanowire FET biosensors

    NASA Astrophysics Data System (ADS)

    Chui, Chi On; Shin, Kyeong-Sik; Mao, Yufei

    2013-09-01

    In this paper, we review our recent development and validation of the ultrasensitive electronic biomolecular assays enabled by our novel amplifying nanowire field-effect transistor (nwFET) biosensors. Our semiconductor nwFET biosensor platform technology performs extreme proximity signal amplification in the electrical domain that requires neither labeling nor enzymes nor optics. We have designed and fabricated the biomolecular assay prototypes and developed the corresponding analytical procedures. We have also confirmed their analytical performance in quantitating key protein biomarker in human serum, demonstrating an ultralow limit of detection and concurrently high output current level for the first time.

  4. Monolithic metal oxide transistors.

    PubMed

    Choi, Yongsuk; Park, Won-Yeong; Kang, Moon Sung; Yi, Gi-Ra; Lee, Jun-Young; Kim, Yong-Hoon; Cho, Jeong Ho

    2015-04-28

    We devised a simple transparent metal oxide thin film transistor architecture composed of only two component materials, an amorphous metal oxide and ion gel gate dielectric, which could be entirely assembled using room-temperature processes on a plastic substrate. The geometry cleverly takes advantage of the unique characteristics of the two components. An oxide layer is metallized upon exposure to plasma, leading to the formation of a monolithic source-channel-drain oxide layer, and the ion gel gate dielectric is used to gate the transistor channel effectively at low voltages through a coplanar gate. We confirmed that the method is generally applicable to a variety of sol-gel-processed amorphous metal oxides, including indium oxide, indium zinc oxide, and indium gallium zinc oxide. An inverter NOT logic device was assembled using the resulting devices as a proof of concept demonstration of the applicability of the devices to logic circuits. The favorable characteristics of these devices, including (i) the simplicity of the device structure with only two components, (ii) the benign fabrication processes at room temperature, (iii) the low-voltage operation under 2 V, and (iv) the excellent and stable electrical performances, together support the application of these devices to low-cost portable gadgets, i.e., cheap electronics. PMID:25777338

  5. Microwave field effect transistor

    NASA Technical Reports Server (NTRS)

    Huang, Ho-Chung (Inventor)

    1989-01-01

    Electrodes of a high power, microwave field effect transistor are substantially matched to external input and output networks. The field effect transistor includes a metal ground plane layer, a dielectric layer on the ground plane layer, a gallium arsenide active region on the dielectric layer, and substantially coplanar spaced source, gate, and drain electrodes having active segments covering the active region. The active segment of the gate electrode is located between edges of the active segments of the source and drain electrodes. The gate and drain electrodes include inactive pads remote from the active segments. The pads are connected directly to the input and output networks. The source electrode is connected to the ground plane layer. The space between the electrodes and the geometry of the electrodes extablish parasitic shunt capacitances and series inductances that provide substantial matches between the input network and the gate electrode and between the output network and the drain electrode. Many of the devices are connected in parallel and share a common active region, so that each pair of adjacent devices shares the same source electrodes and each pair of adjacent devices shares the same drain electrodes. The gate electrodes for the parallel devices are formed by a continuous stripe that extends between adjacent devices and is connected at different points to the common gate pad.

  6. Man-Amplifying Exoskeleton

    NASA Astrophysics Data System (ADS)

    Rosheim, Mark E.

    1990-03-01

    This paper describes a design for a man-amplifying exoskeleton, an electrically powered, articulated frame worn by an operator. The design features modular construction and employ anthropomorphic pitch-yaw joints for arms and legs. These singularity-free designs offer a significant advancement over simple pivot-type joints used in older designs. Twenty-six degrees-of-freedom excluding the hands gives the Man-Amplifier its unique dexterity. A five hundred-pound load capacity is engineered for a diverse range of tasks. Potential applications in emergency rescue work, restoring functionality to the handicapped, and military applications ranging from material handling to an elite fighting core are discussed. A bibliography concludes this paper.

  7. PEAK LIMITING AMPLIFIER

    DOEpatents

    Goldsworthy, W.W.; Robinson, J.B.

    1959-03-31

    A peak voltage amplitude limiting system adapted for use with a cascade type amplifier is described. In its detailed aspects, the invention includes an amplifier having at least a first triode tube and a second triode tube, the cathode of the second tube being connected to the anode of the first tube. A peak limiter triode tube has its control grid coupled to thc anode of the second tube and its anode connected to the cathode of the second tube. The operation of the limiter is controlled by a bias voltage source connected to the control grid of the limiter tube and the output of the system is taken from the anode of the second tube.

  8. DRIFT COMPENSATED DIRECT COUPLED AMPLIFIER

    DOEpatents

    Windsor, A.A.

    1959-05-01

    An improved direct-coupled amplifier having zerolevel drift correction is described. The need for an auxiliary corrective-potential amplifier is eliminated thereby giving protection against overload saturation of the zero- level drift correcting circuit. (T.R.H.)

  9. Helical Fiber Amplifier

    DOEpatents

    Koplow, Jeffrey P.; Kliner, Dahy; Goldberg, Lew

    2002-12-17

    A multi-mode gain fiber is provided which affords substantial improvements in the maximum pulse energy, peak power handling capabilities, average output power, and/or pumping efficiency of fiber amplifier and laser sources while maintaining good beam quality (comparable to that of a conventional single-mode fiber source). These benefits are realized by coiling the multimode gain fiber to induce significant bend loss for all but the lowest-order mode(s).

  10. Cryogenetically Cooled Field Effect Transistors for Low-Noise Systems

    NASA Technical Reports Server (NTRS)

    Wollack, Edward J.; Rabin, Douglas M. (Technical Monitor)

    2002-01-01

    Recent tends in the design, fabrication and use of High-Electron-Mobility-Transistors (HEMT) in low noise amplifiers are reviewed. Systems employing these devices have achieved the lowest system noise for wavelengths greater than three millimeters with relatively modest cryogenic cooling requirements in a variety of ground and space based applications. System requirements which arise in employing such devices in imaging applications are contrasted with other leading coherent detector candidates at microwave wavelengths. Fundamental and practical limitations which arise in the context of microwave application of field effect devices at cryogenic temperatures will be discussed from a component and systems point of view.

  11. Cryogenically Cooled Field Effect Transistors for Low-Noise Systems

    NASA Technical Reports Server (NTRS)

    Wollack, Edward J.

    2002-01-01

    Recent tends in the design, fabrication and use of High-Electron-Mobility-Transistors (HEMT) in low noise amplifiers are reviewed. Systems employing these devices have achieved the lowest system noise for wavelengths greater than three millimeters with relatively modest cryogenic cooling requirements in a variety of ground and space based applications. System requirements which arise in employing such devices in imaging applications are contrasted with other leading coherent detector candidates at microwave wavelengths. Fundamental and practical limitations which arise in the context of microwave application of field effect devices at cryogenic temperatures will be discussed from a component and systems point of view.

  12. Interference-based molecular transistors

    PubMed Central

    Li, Ying; Mol, Jan A.; Benjamin, Simon C.; Briggs, G. Andrew D.

    2016-01-01

    Molecular transistors have the potential for switching with lower gate voltages than conventional field-effect transistors. We have calculated the performance of a single-molecule device in which there is interference between electron transport through the highest occupied molecular orbital and the lowest unoccupied molecular orbital of a single molecule. Quantum interference results in a subthreshold slope that is independent of temperature. For realistic parameters the change in gate potential required for a change in source-drain current of two decades is 20 mV, which is a factor of six smaller than the theoretical limit for a metal-oxide-semiconductor field-effect transistor. PMID:27646692

  13. Interference-based molecular transistors.

    PubMed

    Li, Ying; Mol, Jan A; Benjamin, Simon C; Briggs, G Andrew D

    2016-01-01

    Molecular transistors have the potential for switching with lower gate voltages than conventional field-effect transistors. We have calculated the performance of a single-molecule device in which there is interference between electron transport through the highest occupied molecular orbital and the lowest unoccupied molecular orbital of a single molecule. Quantum interference results in a subthreshold slope that is independent of temperature. For realistic parameters the change in gate potential required for a change in source-drain current of two decades is 20 mV, which is a factor of six smaller than the theoretical limit for a metal-oxide-semiconductor field-effect transistor. PMID:27646692

  14. Multiple pass laser amplifier system

    DOEpatents

    Brueckner, Keith A.; Jorna, Siebe; Moncur, N. Kent

    1977-01-01

    A laser amplification method for increasing the energy extraction efficiency from laser amplifiers while reducing the energy flux that passes through a flux limited system which includes apparatus for decomposing a linearly polarized light beam into multiple components, passing the components through an amplifier in delayed time sequence and recombining the amplified components into an in phase linearly polarized beam.

  15. Improved-Bandwidth Transimpedance Amplifier

    NASA Technical Reports Server (NTRS)

    Chapsky, Jacob

    2009-01-01

    The widest available operational amplifier, with the best voltage and current noise characteristics, is considered for transimpedance amplifier (TIA) applications where wide bandwidth is required to handle fast rising input signals (as for time-of-flight measurement cases). The added amplifier inside the TIA feedback loop can be configured to have slightly lower voltage gain than the bandwidth reduction factor.

  16. Special Component Designs for Differential-Amplifier MMICs

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka

    2010-01-01

    Special designs of two types of electronic components transistors and transmission lines have been conceived to optimize the performances of these components as parts of waveguide-embedded differential-amplifier monolithic microwave integrated circuits (MMICs) of the type described in the immediately preceding article. These designs address the following two issues, the combination of which is unique to these particular MMICs: Each MMIC includes a differential double-strip transmission line that typically has an impedance between 60 and 100 W. However, for purposes of matching of impedances, transmission lines having lower impedances are also needed. The transistors in each MMIC are, more specifically, one or more pair(s) of InP-based high-electron-mobility transistors (HEMTs). Heretofore, it has been common practice to fabricate each such pair as a single device configured in the side-to-side electrode sequence source/gate/drain/gate/source. This configuration enables low-inductance source grounding from the sides of the device. However, this configuration is not suitable for differential operation, in which it is necessary to drive the gates differentially and to feed the output from the drain electrodes differentially. The special transmission-line design provides for three conductors, instead of two, in places where lower impedance is needed. The third conductor is a metal strip placed underneath the differential double-strip transmission line. The third conductor increases the capacitance per unit length of the transmission line by such an amount as to reduce the impedance to between 5 and 15 W. In the special HEMT-pair design, the side-to-side electrode sequence is changed to drain/gate/source/gate/ drain. In addition, the size of the source is reduced significantly, relative to corresponding sizes in prior designs. This reduction is justified by the fact that, by virtue of the differential configuration, the device has an internal virtual ground, and

  17. Ballistic deflection transistors and their application to THz amplification

    NASA Astrophysics Data System (ADS)

    Margala, M.; Wu, H.; Sobolewski, Roman

    2015-10-01

    We present implementation of recently proposed ballistic deflection transistors (BDTs) as THz amplifiers. BDT is a planar device based on InGaAs/InAlAs/InP heterostructure with quasi-ballistic transport obtained in the two-dimensional electron gas layer that facilitates ultra-short transit time and high performance needed for THz-range circuitry. The BDT performance is optimized through its structural modification and the use of high-k dielectrics. Our time-domain, electrical transient measurements demonstrate sub-THz switching performance of a BDT with a ∼1-μm-wide channel. Independently, circuit simulations using experimental parameters of BDTs with a channel width of 430 nm and with the BDTs themselves connected as a multi-stage travelling-wave amplifier, designed for 6-dB gain, predict a 2.7- THz bandwidth with a gain flatness of ±0.3 dB.

  18. High transconductance organic electrochemical transistors

    PubMed Central

    Khodagholy, Dion; Rivnay, Jonathan; Sessolo, Michele; Gurfinkel, Moshe; Leleux, Pierre; Jimison, Leslie H.; Stavrinidou, Eleni; Herve, Thierry; Sanaur, Sébastien; Owens, Róisín M.; Malliaras, George G.

    2013-01-01

    The development of transistors with high gain is essential for applications ranging from switching elements and drivers to transducers for chemical and biological sensing. Organic transistors have become well-established based on their distinct advantages, including ease of fabrication, synthetic freedom for chemical functionalization, and the ability to take on unique form factors. These devices, however, are largely viewed as belonging to the low-end of the performance spectrum. Here we present organic electrochemical transistors with a transconductance in the mS range, outperforming transistors from both traditional and emerging semiconductors. The transconductance of these devices remains fairly constant from DC up to a frequency of the order of 1 kHz, a value determined by the process of ion transport between the electrolyte and the channel. These devices, which continue to work even after being crumpled, are predicted to be highly relevant as transducers in biosensing applications. PMID:23851620

  19. Transistorized converter provides nondissipative regulation

    NASA Technical Reports Server (NTRS)

    1964-01-01

    A transistorized regulator converter efficiently converts fluctuating input voltages to a constant output voltage, avoiding the use of saturable reactors. It is nondissipative in operation and functions in an open loop through variable duty cycles.

  20. Solder Bonding for Power Transistors

    NASA Technical Reports Server (NTRS)

    Snytsheuvel, H. A.; Mandel, H.

    1985-01-01

    Indium solder boosts power rating and facilitates circuit changes. Efficient heat conduction from power transistor to heat sink provided by layer of indium solder. Low melting point of indium solder (141 degrees C) allows power transistor to be removed, if circuit must be reworked, without disturbing other components mounted with ordinary solder that melts at 181 degrees C. Solder allows devices operated at higher power levels than does conventional attachment by screws.

  1. MOS-transistor power switches

    NASA Astrophysics Data System (ADS)

    Konev, Iu. I.; Mashukov, E. V.

    The output characteristics of vertical-channel MOS power transistors are analyzed. It is shown that it is possible to remove the basic energy and weight-volume constraints associated with the nonlinearity of the characeristics of devices with carrier injection (i.e., diodes, transistors, and thyristors). This makes it possible to increase the specific power of all types of power switches. The discussion covers switches for ac and dc power circuits, low-voltage rectifiers, and switches with pulse width modulation.

  2. Amplifying Electrochemical Indicators

    NASA Technical Reports Server (NTRS)

    Fan, Wenhong; Li, Jun; Han, Jie

    2004-01-01

    Dendrimeric reporter compounds have been invented for use in sensing and amplifying electrochemical signals from molecular recognition events that involve many chemical and biological entities. These reporter compounds can be formulated to target specific molecules or molecular recognition events. They can also be formulated to be, variously, hydrophilic or amphiphilic so that they are suitable for use at interfaces between (1) aqueous solutions and (2) electrodes connected to external signal-processing electronic circuits. The invention of these reporter compounds is expected to enable the development of highly miniaturized, low-power-consumption, relatively inexpensive, mass-producible sensor units for diverse applications.

  3. High voltage electrical amplifier having a short rise time

    DOEpatents

    Christie, David J.; Dallum, Gregory E.

    1991-01-01

    A circuit, comprising an amplifier and a transformer is disclosed that produces a high power pulse having a fast response time, and that responds to a digital control signal applied through a digital-to-analog converter. The present invention is suitable for driving a component such as an electro-optic modulator with a voltage in the kilovolt range. The circuit is stable at high frequencies and during pulse transients, and its impedance matching circuit matches the load impedance with the output impedance. The preferred embodiment comprises an input stage compatible with high-speed semiconductor components for amplifying the voltage of the input control signal, a buffer for isolating the input stage from the output stage; and a plurality of current amplifiers connected to the buffer. Each current amplifier is connected to a field effect transistor (FET), which switches a high voltage power supply to a transformer which then provides an output terminal for driving a load. The transformer comprises a plurality of transmission lines connected to the FETs and the load. The transformer changes the impedance and voltage of the output. The preferred embodiment also comprises a low voltage power supply for biasing the FETs at or near an operational voltage.

  4. Evolvable circuit with transistor-level reconfigurability

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)

    2004-01-01

    An evolvable circuit includes a plurality of reconfigurable switches, a plurality of transistors within a region of the circuit, the plurality of transistors having terminals, the plurality of transistors being coupled between a power source terminal and a power sink terminal so as to be capable of admitting power between the power source terminal and the power sink terminal, the plurality of transistors being coupled so that every transistor terminal to transistor terminal coupling within the region of the circuit comprises a reconfigurable switch.

  5. Thermal considerations in the use of solid state power amplifiers on the GOES spacecraft

    NASA Technical Reports Server (NTRS)

    Mallette, L.; Darby, S.; Baatz, M.; Ujihara, K.

    1984-01-01

    The use of solid state power amplifiers (SSPA) in satellites has been quite prevalent in several frequency bands. This trend is evidenced by the use of SSPAs at Hughes in the UHF band (Leasat/Syncom IV), S band (GOES), C band (Telstar), and SHF band. The junction temperature of the transistor is the driving requirement which determines the lifetime of the transistor, SSPA, and the payload. This temperature is determined by the transistor characteristics, use of the device, and mounting temperature of the SSPA. The temperature of the spacecraft in the area of the SSPA can be controlled by active or passive means. The various factors and interrelationships used to calculate and control the temperatures of SSPAs are described. The thermal design and calculation of junction temperatures are exemplified with the Geostationary Operational Environmental Satellite spacecraft.

  6. Universal Signal Conditioning Amplifier

    NASA Technical Reports Server (NTRS)

    Kinney, Frank

    1997-01-01

    The Technological Research and Development Authority (TRDA) and NASA-KSC entered into a cooperative agreement in March of 1994 to achieve the utilization and commercialization of a technology development for benefiting both the Space Program and U.S. industry on a "dual-use basis". The technology involved in this transfer is a new, unique Universal Conditioning Amplifier (USCA) used in connection with various types of transducers. The project was initiated in partnership with I-Net Corporation, Lockheed Martin Telemetry & Instrumentation (formerly Loral Test and Information Systems) and Brevard Community College. The project consists of designing, miniaturizing, manufacturing, and testing an existing prototype of USCA that was developed for NASA-KSC by the I-Net Corporation. The USCA is a rugged and field-installable self (or remotely)- programmable amplifier that works in combination with a tag random access memory (RAM) attached to various types of transducers. This summary report comprises performance evaluations, TRDA partnership tasks, a project summary, project milestones and results.

  7. DIAMOND AMPLIFIED PHOTOCATHODES.

    SciTech Connect

    SMEDLEY,J.; BEN-ZVI, I.; BOHON, J.; CHANG, X.; GROVER, R.; ISAKOVIC, A.; RAO, T.; WU, Q.

    2007-11-26

    High-average-current linear electron accelerators require photoinjectors capable of delivering tens to hundreds of mA average current, with peak currents of hundreds of amps. Standard photocathodes face significant challenges in meeting these requirements, and often have short operational lifetimes in an accelerator environment. We report on recent progress toward development of secondary emission amplifiers for photocathodes, which are intended to increase the achievable average current while protecting the cathode from the accelerator. The amplifier is a thin diamond wafer which converts energetic (few keV) primary electrons into hundreds of electron-hole pairs via secondary electron emission. The electrons drift through the diamond under an external bias and are emitted into vacuum via a hydrogen-terminated surface with negative electron affinity (NEA). Secondary emission gain of over 200 has been achieved. Two methods of patterning diamond, laser ablation and reactive-ion etching (RIE), are being developed to produce the required geometry. A variety of diagnostic techniques, including FTIR, SEM and AFM, have been used to characterize the diamonds.

  8. High-Efficiency Harmonically Terminated Diode and Transistor Rectifiers

    SciTech Connect

    Roberg, M; Reveyrand, T; Ramos, I; Falkenstein, EA; Popovic, Z

    2012-12-01

    This paper presents a theoretical analysis of harmonically terminated high-efficiency power rectifiers and experimental validation on a class-C single Schottky-diode rectifier and a class-F-1 GaN transistor rectifier. The theory is based on a Fourier analysis of current and voltage waveforms, which arise across the rectifying element when different harmonic terminations are presented at its terminals. An analogy to harmonically terminated power amplifier (PA) theory is discussed. From the analysis, one can obtain an optimal value for the dc load given the RF circuit design. An upper limit on rectifier efficiency is derived for each case as a function of the device on-resistance. Measured results from fundamental frequency source-pull measurement of a Schottky diode rectifier with short-circuit terminations at the second and third harmonics are presented. A maximal device rectification efficiency of 72.8% at 2.45 GHz matches the theoretical prediction. A 2.14-GHz GaN HEMT rectifier is designed based on a class-F-1 PA. The gate of the transistor is terminated in an optimal impedance for self-synchronous rectification. Measurements of conversion efficiency and output dc voltage for varying gate RF impedance, dc load, and gate bias are shown with varying input RF power at the drain. The rectifier demonstrates an efficiency of 85% for a 10-W input RF power at the transistor drain with a dc voltage of 30 V across a 98-Omega resistor.

  9. Linearisation of asymmetrical Doherty amplifier by the even-order non-linear signals

    NASA Astrophysics Data System (ADS)

    Maleš-Ilić, Nataša; Atanasković, Aleksandar; Blau, Kurt; Hein, Matthias

    2016-08-01

    This paper considers the linearisation of an asymmetrical two-way Doherty amplifier by the method that uses the second harmonics and fourth-order non-linear signals for linearisation. These even-order signals for linearisation are extracted at the output of the peaking amplifier, adjusted in amplitude and phase and injected at the input and output of the carrier amplifier transistor in the Doherty configuration. The effect of linearisation has been experimentally confirmed on a fabricated asymmetrical Doherty amplifier with the additional circuit for linearisation. The suppression of the third-order intermodulation products has been carried out for two-tone test, 64QAM and WCDMA digitally modulated signals in a range of signal power.

  10. An HEMT-Based Cryogenic Charge Amplifier for Sub-kelvin Semiconductor Radiation Detectors

    NASA Astrophysics Data System (ADS)

    Phipps, A.; Sadoulet, B.; Juillard, A.; Jin, Y.

    2016-07-01

    We present the design and noise performance of a fully cryogenic (T=4 K) high-electron mobility transistor (HEMT)-based charge amplifier for readout of sub-kelvin semiconductor radiation detectors. The amplifier is being developed for use in direct detection dark matter searches such as the cryogenic dark matter search and will allow these experiments to probe weakly interacting massive particle masses below 10 GeV/c^2 while retaining background discrimination. The amplifier dissipates ≈ 1 mW of power and provides an open loop voltage gain of several hundreds. The measured noise performance is better than that of JFET-based charge amplifiers and is dominated by the noise of the input HEMT. An optimal filter calculation using the measured closed loop noise and typical detector characteristics predicts a charge resolution of σ _q=106 eV (35 electrons) for leakage currents below 4 × 10^{-15} A.

  11. Low-noise two-wired buffer electrodes for bioelectric amplifiers.

    PubMed

    Degen, Thomas; Torrent, Simon; Jäckel, Heinz

    2007-07-01

    Active buffer electrodes are known to improve the immunity of bioelectric recordings against power line interferences. A survey of published work reveals that buffer electrodes are almost exclusively designed using operational amplifiers (opamps). In this paper, we discuss the advantage of utilizing a single transistor instead. This allows for a simple electrode, which is small and requires only two wires. In addition, a single transistor adds considerably less noise when compared to an opamp with the same power consumption. We then discuss output resistance and gain as well as their respective effect on the common mode rejection ratio (CMRR). Finally, we demonstrate the use of two-wired buffer electrodes for a bioelectric amplifier.

  12. Few-layer molybdenum disulfide transistors and circuits for high-speed flexible electronics

    PubMed Central

    Cheng, Rui; Jiang, Shan; Chen, Yu; Liu, Yuan; Weiss, Nathan; Cheng, Hung-Chieh; Wu, Hao; Huang, Yu; Duan, Xiangfeng

    2014-01-01

    Two-dimensional layered materials, such as molybdenum disulfide, are emerging as an exciting material system for future electronics due to their unique electronic properties and atomically thin geometry. Here we report a systematic investigation of MoS2 transistors with optimized contact and device geometry, to achieve self-aligned devices with performance including an intrinsic gain over 30, an intrinsic cut-off frequency fT up to 42 GHz and a maximum oscillation frequency fMAX up to 50 GHz, exceeding the reported values for MoS2 transistors to date (fT ~ 0.9 GHz, fMAX ~ 1 GHz). Our results show that logic inverters or radio frequency amplifiers can be formed by integrating multiple MoS2 transistors on quartz or flexible substrates with voltage gain in the gigahertz regime. This study demonstrates the potential of two-dimensional layered semiconductors for high-speed flexible electronics. PMID:25295573

  13. High-Power, High-Frequency Si-Based (SiGe) Transistors Developed

    NASA Technical Reports Server (NTRS)

    Ponchak, George E.

    2002-01-01

    Future NASA, DOD, and commercial products will require electronic circuits that have greater functionality and versatility but occupy less space and cost less money to build and integrate than current products. System on a Chip (SOAC), a single semiconductor substrate containing circuits that perform many functions or containing an entire system, is widely recognized as the best technology for achieving low-cost, small-sized systems. Thus, a circuit technology is required that can gather, process, store, and transmit data or communications. Since silicon-integrated circuits are already used for data processing and storage and the infrastructure that supports silicon circuit fabrication is very large, it is sensible to develop communication circuits on silicon so that all the system functions can be integrated onto a single wafer. Until recently, silicon integrated circuits did not function well at the frequencies required for wireless or microwave communications, but with the introduction of small amounts of germanium into the silicon to make silicon-germanium (SiGe) transistors, silicon-based communication circuits are possible. Although microwavefrequency SiGe circuits have been demonstrated, there has been difficulty in obtaining the high power from their transistors that is required for the amplifiers of a transmitter, and many researchers have thought that this could not be done. The NASA Glenn Research Center and collaborators at the University of Michigan have developed SiGe transistors and amplifiers with state-of-the-art output power at microwave frequencies from 8 to 20 GHz. These transistors are fabricated using standard silicon processing and may be integrated with CMOS integrated circuits on a single chip. A scanning electron microscope image of a typical SiGe heterojunction bipolar transistor is shown in the preceding photomicrograph. This transistor achieved a record output power of 550 mW and an associated power-added efficiency of 33 percent at 8

  14. Cryogenic Design of the Deep Space Network Large Array Low-Noise Amplifier System

    NASA Astrophysics Data System (ADS)

    Britcliffe, M. J.; Hanson, T. R.; Franco, M. M.

    2004-05-01

    This article describes the cryogenic design and performance of a prototype low-noise amplifier (LNA) system for the Deep Space Network (DSN) Large Array task. The system is used to cool a dual-frequency feed system equipped with high-electron mobility transistor (HEMT) low-noise amplifiers and the associated support electronics. The LNA/feed system operates at a temperature under 18 K. The system is designed to be manufactured at minimum cost. The design considerations, including the cryocooler to be used, vacuum system, microwave interconnects, mechanical components, and radiation shielding, are discussed.

  15. The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier

    SciTech Connect

    J.G. Kulpin, K.J. Kleman, R.A. Legg

    2012-07-01

    A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

  16. Medium power amplifiers covering 90 - 130 GHz for telescope local oscillators

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Bryerton, Eric; Pukala, David; Peralta, Alejandro; Hu, Ming; Schmitz, Adele

    2005-01-01

    This paper describes a set of power amplifier (PA) modules containing InP High Electron Mobility Transistor (HEMT) Monolithic Millimeter-wave Integrated Circuit (MMIC) chips. The chips were designed and optimized for local oscillator sources in the 90-130 GHz band for the Atacama Large Millimeter Array telescope. The modules feature 20-45 mW of output power, to date the highest power from solid state HEMT MMIC modules above 110 GHz.

  17. Nanoscale electromechanical parametric amplifier

    DOEpatents

    Aleman, Benjamin Jose; Zettl, Alexander

    2016-09-20

    This disclosure provides systems, methods, and apparatus related to a parametric amplifier. In one aspect, a device includes an electron source electrode, a counter electrode, and a pumping electrode. The electron source electrode may include a conductive base and a flexible conductor. The flexible conductor may have a first end and a second end, with the second end of the flexible conductor being coupled to the conductive base. A cross-sectional dimension of the flexible conductor may be less than about 100 nanometers. The counter electrode may be disposed proximate the first end of the flexible conductor and spaced a first distance from the first end of the flexible conductor. The pumping electrode may be disposed proximate a length of the flexible conductor and spaced a second distance from the flexible conductor.

  18. Wavelength tunable alexandrite regenerative amplifier

    SciTech Connect

    Harter, D.J.; Bado, P.

    1988-11-01

    We describe a wavelength tunable alexandrite regenerative amplifier which is used to amplify nanosecond slices from a single-frequency cw dye laser or 50-ps pulses emitted by a diode laser to energies in the 10-mJ range. The amplified 5-ns slices generated by the cw-pumped line narrowed dye laser are Fourier transform limited. The 50-ps pulses emitted by a gain-switched diode laser are amplified by more than 10 orders of magnitude in a single stage.

  19. Optical Amplifier for Space Applications

    NASA Technical Reports Server (NTRS)

    Fork, Richard L.; Cole, Spencer T.; Gamble, Lisa J.; Diffey, William M.; Keys, Andrew S.

    1999-01-01

    We describe an optical amplifier designed to amplify a spatially sampled component of an optical wavefront to kilowatt average power. The goal is means for implementing a strategy of spatially segmenting a large aperture wavefront, amplifying the individual segments, maintaining the phase coherence of the segments by active means, and imaging the resultant amplified coherent field. Applications of interest are the transmission of space solar power over multi-megameter distances, as to distant spacecraft, or to remote sites with no preexisting power grid.

  20. Reflex ring laser amplifier system

    DOEpatents

    Summers, Mark A.

    1985-01-01

    A laser pulse is injected into an unstable ring resonator-amplifier structure. Inside this resonator the laser pulse is amplified, spatially filtered and magnified. The laser pulse is recirculated in the resonator, being amplified, filtered and magnified on each pass. The magnification is chosen so that the beam passes through the amplifier in concentric non-overlapping regions similar to a single pass MOPA. After a number of passes around the ring resonator the laser pulse is spatially large enough to exit the ring resonator system by passing around an output mirror.

  1. A pH sensor with a double-gate silicon nanowire field-effect transistor

    NASA Astrophysics Data System (ADS)

    Ahn, Jae-Hyuk; Kim, Jee-Yeon; Seol, Myeong-Lok; Baek, David J.; Guo, Zheng; Kim, Chang-Hoon; Choi, Sung-Jin; Choi, Yang-Kyu

    2013-02-01

    A pH sensor composed of a double-gate silicon nanowire field-effect transistor (DG Si-NW FET) is demonstrated. The proposed DG Si-NW FET allows the independent addressing of the gate voltage and hence improves the sensing capability through an application of asymmetric gate voltage between the two gates. One gate is a driving gate which controls the current flow, and the other is a supporting gate which amplifies the shift of the threshold voltage, which is a sensing metric, and which arises from changes in the pH. The pH signal is also amplified through modulation of the gate oxide thickness.

  2. Passivated ambipolar black phosphorus transistors

    NASA Astrophysics Data System (ADS)

    Yue, Dewu; Lee, Daeyeong; Jang, Young Dae; Choi, Min Sup; Nam, Hye Jin; Jung, Duk-Young; Yoo, Won Jong

    2016-06-01

    We report the first air-passivated ambipolar BP transistor formed by applying benzyl viologen, which serves as a surface charge transfer donor for BP flakes. The passivated BP devices exhibit excellent stability under both an ambient atmosphere and vacuum; their transistor performance is maintained semi-permanently. Unlike their intrinsic p-type properties, passivated BP devices present advantageous ambipolar properties with much higher electron mobility up to ~83 cm2 V-1 s-1 from 2-terminal measurement at 300 K, compared to other reported studies on n-type BP transistors. On the basis of the n-type doping effect that originated from benzyl viologen, we also systematically investigated the BP thickness dependence of our devices on electrical properties, in which we found the best electron transport performance to be attained when an ~10 nm thick BP flake was used.We report the first air-passivated ambipolar BP transistor formed by applying benzyl viologen, which serves as a surface charge transfer donor for BP flakes. The passivated BP devices exhibit excellent stability under both an ambient atmosphere and vacuum; their transistor performance is maintained semi-permanently. Unlike their intrinsic p-type properties, passivated BP devices present advantageous ambipolar properties with much higher electron mobility up to ~83 cm2 V-1 s-1 from 2-terminal measurement at 300 K, compared to other reported studies on n-type BP transistors. On the basis of the n-type doping effect that originated from benzyl viologen, we also systematically investigated the BP thickness dependence of our devices on electrical properties, in which we found the best electron transport performance to be attained when an ~10 nm thick BP flake was used. Electronic supplementary information (ESI) available: Transfer characteristics of BP field effect transistors (BV1-BV4) (Fig. S1 and S2 and Table S1); output characteristics of BP field effect transistors in different directions (Fig. S3

  3. Synergistic effect of mixed neutron and gamma irradiation in bipolar operational amplifier OP07

    NASA Astrophysics Data System (ADS)

    Yan, Liu; Wei, Chen; Shanchao, Yang; Xiaoming, Jin; Chaohui, He

    2016-09-01

    This paper presents the synergistic effects in bipolar operational amplifier OP07. The radiation effects are studied by neutron beam, gamma ray, and mixed neutron/gamma ray environments. The characterateristics of the synergistic effects are studied through comparison of different experiment results. The results show that the bipolar operational amplifier OP07 exhibited significant synergistic effects in the mixed neutron and gamma irradiation. The bipolar transistor is identified as the most radiation sensitive unit of the operational amplifier. In this paper, a series of simulations are performed on bipolar transistors in different radiation environments. In the theoretical simulation, the geometric model and calculations based on the Medici toolkit are built to study the radiation effects in bipolar components. The effect of mixed neutron and gamma irradiation is simulated based on the understanding of the underlying mechanisms of radiation effects in bipolar transistors. The simulated results agree well with the experimental data. The results of the experiments and simulation indicate that the radiation effects in the bipolar devices subjected to mixed neutron and gamma environments is not a simple combination of total ionizing dose (TID) effects and displacement damage. The data suggests that the TID effect could enhance the displacement damage. The synergistic effect should not be neglected in complex radiation environments.

  4. Passivated ambipolar black phosphorus transistors.

    PubMed

    Yue, Dewu; Lee, Daeyeong; Jang, Young Dae; Choi, Min Sup; Nam, Hye Jin; Jung, Duk-Young; Yoo, Won Jong

    2016-07-01

    We report the first air-passivated ambipolar BP transistor formed by applying benzyl viologen, which serves as a surface charge transfer donor for BP flakes. The passivated BP devices exhibit excellent stability under both an ambient atmosphere and vacuum; their transistor performance is maintained semi-permanently. Unlike their intrinsic p-type properties, passivated BP devices present advantageous ambipolar properties with much higher electron mobility up to ∼83 cm(2) V(-1) s(-1) from 2-terminal measurement at 300 K, compared to other reported studies on n-type BP transistors. On the basis of the n-type doping effect that originated from benzyl viologen, we also systematically investigated the BP thickness dependence of our devices on electrical properties, in which we found the best electron transport performance to be attained when an ∼10 nm thick BP flake was used. PMID:27283027

  5. High current gain transistor laser.

    PubMed

    Liang, Song; Qiao, Lijun; Zhu, Hongliang; Wang, Wei

    2016-06-10

    A transistor laser (TL), having the structure of a transistor with multi-quantum wells near its base region, bridges the functionality gap between lasers and transistors. However, light emission is produced at the expense of current gain for all the TLs reported up to now, leading to a very low current gain. We propose a novel design of TLs, which have an n-doped InP layer inserted in the emitter ridge. Numerical studies show that a current flow aperture for only holes can be formed in the center of the emitter ridge. As a result, the common emitter current gain can be as large as 143.3, which is over 15 times larger than that of a TL without the aperture. Besides, the effects of nonradiative recombination defects can be reduced greatly because the flow of holes is confined in the center region of the emitter ridge.

  6. Magnetic Vortex Based Transistor Operations

    PubMed Central

    Kumar, D.; Barman, S.; Barman, A.

    2014-01-01

    Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fan–out operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT). PMID:24531235

  7. High current gain transistor laser

    NASA Astrophysics Data System (ADS)

    Liang, Song; Qiao, Lijun; Zhu, Hongliang; Wang, Wei

    2016-06-01

    A transistor laser (TL), having the structure of a transistor with multi-quantum wells near its base region, bridges the functionality gap between lasers and transistors. However, light emission is produced at the expense of current gain for all the TLs reported up to now, leading to a very low current gain. We propose a novel design of TLs, which have an n-doped InP layer inserted in the emitter ridge. Numerical studies show that a current flow aperture for only holes can be formed in the center of the emitter ridge. As a result, the common emitter current gain can be as large as 143.3, which is over 15 times larger than that of a TL without the aperture. Besides, the effects of nonradiative recombination defects can be reduced greatly because the flow of holes is confined in the center region of the emitter ridge.

  8. High current gain transistor laser

    PubMed Central

    Liang, Song; Qiao, Lijun; Zhu, Hongliang; Wang, Wei

    2016-01-01

    A transistor laser (TL), having the structure of a transistor with multi-quantum wells near its base region, bridges the functionality gap between lasers and transistors. However, light emission is produced at the expense of current gain for all the TLs reported up to now, leading to a very low current gain. We propose a novel design of TLs, which have an n-doped InP layer inserted in the emitter ridge. Numerical studies show that a current flow aperture for only holes can be formed in the center of the emitter ridge. As a result, the common emitter current gain can be as large as 143.3, which is over 15 times larger than that of a TL without the aperture. Besides, the effects of nonradiative recombination defects can be reduced greatly because the flow of holes is confined in the center region of the emitter ridge. PMID:27282466

  9. Suicide Risk: Amplifiers and Attenuators.

    ERIC Educational Resources Information Center

    Plutchik, Robert; Van Praag, Herman M.

    1994-01-01

    Attempts to integrate findings on correlates of suicide and violent risk in terms of a theory called a two-stage model of countervailing forces, which assumes that the strength of aggressive impulses is modified by amplifiers and attenuators. The vectorial interaction of amplifiers and attenuators creates an unstable equilibrium making prediction…

  10. Laser amplifier developments at Mercury

    SciTech Connect

    Rose, E.A.; Brucker, J.P.; Honig, E.M.; McCown, A.W.; Romero, V.O.; York, G.W.

    1993-09-01

    Electron-beam pumped laser amplifiers have been modified to address the mission of krypton-fluoride excimer laser technology development. Methods are described for improving the performance and reliability of two pre-existing amplifiers at minimal cost and time. Preliminary performance data are presented to support the credibility of the approach.

  11. Phonon thermoelectric transistors and rectifiers

    NASA Astrophysics Data System (ADS)

    Jiang, Jian-Hua; Kulkarni, Manas; Segal, Dvira; Imry, Yoseph

    2015-07-01

    We describe nonlinear phonon-thermoelectric devices where charge current and electronic and phononic heat currents are coupled, driven by voltage and temperature biases, when phonon-assisted inelastic processes dominate the transport. Our thermoelectric transistors and rectifiers can be realized in a gate-tunable double quantum-dot system embedded in a nanowire which is realizable within current technology. The inelastic electron-phonon scattering processes are found to induce pronounced charge, heat, and cross rectification effects, as well as a thermal transistor effect that, remarkably, can appear in the present model even in the linear-response regime without relying on the onset of negative differential thermal conductance.

  12. TILBW Bipolar Power Switching Transistor

    NASA Astrophysics Data System (ADS)

    Silard, Andrei P.; Nani, Gabriel

    1989-03-01

    The work reports the development of TILBW (Two Interdigitation Levels with heavily-doped Base Wells) bipolar power switching transistors, which combine the main advantages of both TIL and GAT devices. The TILBW transistors exhibit the following many-fold advantages in comparison with identical, yet conventional devices of the same class (identical area and case) processed simultaneously: a reduction of the turn-on time by a factor of ˜ 20; a two-fold reduction of the fall time tf; an ˜ 18-percent increase of VCEO(SUS); an ˜ 23-percent increase of VCBO; an enhanced RBSOA.

  13. Programmable, automated transistor test system

    NASA Technical Reports Server (NTRS)

    Truong, L. V.; Sundburg, G. R.

    1986-01-01

    A programmable, automated transistor test system was built to supply experimental data on new and advanced power semiconductors. The data will be used for analytical models and by engineers in designing space and aircraft electric power systems. A pulsed power technique was used at low duty cycles in a nondestructive test to examine the dynamic switching characteristic curves of power transistors in the 500 to 1000 V, 10 to 100 A range. Data collection, manipulation, storage, and output are operator interactive but are guided and controlled by the system software.

  14. Solid State Power Amplifier for 805 MegaHertz at the Los Alamos Neutron Science Center

    SciTech Connect

    Davis, J.L.; Lyles, J.T.M.

    1998-10-19

    Particle accelerators for protons, electrons, and other ion species often use high-power vacuum tubes for RF amplification, due to the high RF power requirements to accelerate these particles with high beam currents. The final power amplifier stages driving large accelerators are unable to be converted to solid-state devices with the present technology. In some instances, radiation levels preclude the use of transistors near beamlines. Work is being done worldwide to replace the RF power stages under about ten kilowatts CW with transistor amplifiers, due to the lower maintenance costs and obsolescence of power tubes in these ranges. This is especially practical where the stages drive fifty Ohm impedance and are not located in high radiation zones. The authors are doing this at the Los Alamos Neutron Science Center (LANSCE) proton linear accelerator (linac) in New Mexico. They replaced a physically-large air-cooled UHF power amplifier using a tetrode electron tube with a compact water-cooled unit based on modular amplifier pallets developed at LANSCE. Each module uses eight push-pull bipolar power transistor pairs operated in class AB. Four pallets can easily provide up to 2,800 watts of continuous RF at 805 MHz. A radial splitter and combiner parallels the modules. This amplifier has proven to be completely reliable after over 10,000 hours of operation without failure. A second unit was constructed and installed for redundancy, and the old tetrode system was removed in 1998. The compact packaging for cooling, DC power, impedance matching, RF interconnection, and power combining met the electrical and mechanical requirements. CRT display of individual collector currents and RF levels is made possible with built-in samplers and a VXI data acquisition unit.

  15. Microchannels as axonal amplifiers.

    PubMed

    Fitzgerald, James J; Lacour, Stéphanie P; McMahon, Stephen B; Fawcett, James W

    2008-03-01

    An implantable neural interface capable of reliable long-term high-resolution recording from peripheral nerves has yet to be developed. Device design is challenging because extracellular axonal signals are very small, decay rapidly with distance from the axon, and in myelinated fibres are concentrated close to nodes of Ranvier, which are around 1 mum long and spaced several hundred micrometers apart. We present a finite element model examining the electrical behavior of axons in microchannels, and demonstrate that confining axons in such channels substantially amplifies the extracellular signal. For example, housing a 10-microm myelinated axon in a 1-cm-long channel with a 1000-microm(2) cross section is predicted to generate a peak extracellular voltage of over 10 mV. Furthermore, there is little radial signal decay within the channel, and a smooth axial variation of signal amplitude along the channel, irrespective of node location. Additional benefits include a greater extracellular voltage generated by large myelinated fibres compared to small unmyelinated axons, and the reduction of gain to unity at the end of the channel which ensures that there can be no crosstalk with electrodes in other channels nearby. A microchannel architecture seems well suited to the requirements of a peripheral nerve interface.

  16. DIAMOND AMPLIFIER FOR PHOTOCATHODES.

    SciTech Connect

    RAO,T.; BEN-ZVI,I.; BURRILL,A.; CHANG,X.; HULBERT,S.; JOHNSON,P.D.; KEWISCH,J.

    2004-06-21

    We report a new approach to the generation of high-current, high-brightness electron beams. Primary electrons are produced by a photocathode (or other means) and are accelerated to a few thousand electron-volts, then strike a specially prepared diamond window. The large Secondary Electron Yield (SEY) provides a multiplication of the number of electrons by about two orders of magnitude. The secondary electrons drift through the diamond under an electric field and emerge into the accelerating proper of the ''gun'' through a Negative Electron Affinity surface of the diamond. The advantages of the new approach include the following: (1) Reduction of the number of primary electrons by the large SEY, i.e. a very low laser power in a photocathode producing the primaries. (2) Low thermal emittance due to the NEA surface and the rapid thermalization of the electrons. (3) Protection of the cathode from possible contamination from the gun, allowing the use of large quantum efficiency but sensitive cathodes. (4) Protection of the gun from possible contamination by the cathode, allowing the use of superconducting gun cavities. (5) Production of high average currents, up to ampere class. (6) Encapsulated design, making the ''load-lock'' systems unnecessary. This paper presents the criteria that need to be taken into account in designing the amplifier.

  17. The Integration and Applications of Organic Thin Film Transistors and Ferroelectric Polymers

    NASA Astrophysics Data System (ADS)

    Hsu, Yu-Jen

    Organic thin film transistors and ferroelectric polymer (polyvinylidene difluoride) sheet material are integrated to form various sensors for stress/strain, acoustic wave, and Infrared (heat) sensing applications. Different from silicon-based transistors, organic thin film transistors can be fabricated and processed in room-temperature and integrated with a variety of substrates. On the other hand, polyvinylidene difluoride (PVDF) exhibits ferroelectric properties that are highly useful for sensor applications. The wide frequency bandwidth (0.001 Hz to 10 GHz), vast dynamic range (100n to 10M psi), and high elastic compliance (up to 3 percent) make PVDF a more suitable candidate over ceramic piezoelectric materials for thin and flexible sensor applications. However, the low Curie temperature may have impeded its integration with silicon technology. Organic thin film transistors, however, do not have the limitation of processing temperature, hence can serve as transimpedance amplifiers to convert the charge signal generated by PVDF into current signal that are more measurable and less affected by any downstream parasitics. Piezoelectric sensors are useful for a range of applications, but passive arrays suffer from crosstalk and signal attenuation which have complicated the development of array-based PVDF sensors. We have used organic field effect transistors, which are compatible with the low Curie temperature of a flexible piezoelectric polymer,PVDF, to monolithically fabricate transimpedance amplifiers directly on the sensor surface and convert the piezoelectric charge signal into a current signal which can be detected even in the presence of parasitic capacitances. The device couples the voltage generated by the PVDF film under strain into the gate of the organic thin film transistors (OFET) using an arrangement that allows the full piezoelectric voltage to couple to the channel, while also increasing the charge retention time. A bipolar detector is created by

  18. Silicon on insulator self-aligned transistors

    DOEpatents

    McCarthy, Anthony M.

    2003-11-18

    A method for fabricating thin-film single-crystal silicon-on-insulator (SOI) self-aligned transistors. Standard processing of silicon substrates is used to fabricate the transistors. Physical spaces, between the source and gate, and the drain and gate, introduced by etching the polysilicon gate material, are used to provide connecting implants (bridges) which allow the transistor to perform normally. After completion of the silicon substrate processing, the silicon wafer is bonded to an insulator (glass) substrate, and the silicon substrate is removed leaving the transistors on the insulator (glass) substrate. Transistors fabricated by this method may be utilized, for example, in flat panel displays, etc.

  19. Differential InP HEMT MMIC Amplifiers Embedded in Waveguides

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka; Schlecht, Erich; Samoska, Lorene

    2009-01-01

    Monolithic microwave integrated-circuit (MMIC) amplifiers of a type now being developed for operation at frequencies of hundreds of gigahertz contain InP high-electron-mobility transistors (HEMTs) in a differential configuration. The differential configuration makes it possible to obtain gains greater than those of amplifiers having the single-ended configuration. To reduce losses associated with packaging, the MMIC chips are designed integrally with, and embedded in, waveguide packages, with the additional benefit that the packages are compact enough to fit into phased transmitting and/or receiving antenna arrays. Differential configurations (which are inherently balanced) have been used to extend the upper limits of operating frequencies of complementary metal oxide/semiconductor (CMOS) amplifiers to the microwave range but, until now, have not been applied in millimeter- wave amplifier circuits. Baluns have traditionally been used to transform from single-ended to balanced configurations, but baluns tend to be lossy. Instead of baluns, finlines are used to effect this transformation in the present line of development. Finlines have been used extensively to drive millimeter- wave mixers in balanced configurations. In the present extension of the finline balancing concept, finline transitions are integrated onto the affected MMICs (see figure). The differential configuration creates a virtual ground within each pair of InP HEMT gate fingers, eliminating the need for inductive vias to ground. Elimination of these vias greatly reduces parasitic components of current and the associated losses within an amplifier, thereby enabling more nearly complete utilization of the full performance of each transistor. The differential configuration offers the additional benefit of multiplying (relative to the single-ended configuration) the input and output impedances of each transistor by a factor of four, so that it is possible to use large transistors that would otherwise have

  20. Analysing organic transistors based on interface approximation

    SciTech Connect

    Akiyama, Yuto; Mori, Takehiko

    2014-01-15

    Temperature-dependent characteristics of organic transistors are analysed thoroughly using interface approximation. In contrast to amorphous silicon transistors, it is characteristic of organic transistors that the accumulation layer is concentrated on the first monolayer, and it is appropriate to consider interface charge rather than band bending. On the basis of this model, observed characteristics of hexamethylenetetrathiafulvalene (HMTTF) and dibenzotetrathiafulvalene (DBTTF) transistors with various surface treatments are analysed, and the trap distribution is extracted. In turn, starting from a simple exponential distribution, we can reproduce the temperature-dependent transistor characteristics as well as the gate voltage dependence of the activation energy, so we can investigate various aspects of organic transistors self-consistently under the interface approximation. Small deviation from such an ideal transistor operation is discussed assuming the presence of an energetically discrete trap level, which leads to a hump in the transfer characteristics. The contact resistance is estimated by measuring the transfer characteristics up to the linear region.

  1. Optimization of Vertical Double-Diffused Metal-Oxide Semiconductor (VDMOS) Power Transistor Structure for Use in High Frequencies and Medical Devices.

    PubMed

    Farhadi, Rozita; Farhadi, Bita

    2014-01-01

    Power transistors, such as the vertical, double-diffused, metal-oxide semiconductor (VDMOS), are used extensively in the amplifier circuits of medical devices. The aim of this research was to construct a VDMOS power transistor with an optimized structure to enhance the operation of medical devices. First, boron was implanted in silicon by implanting unclamped inductive switching (UIS) and a Faraday shield. The Faraday shield was implanted in order to replace the gate-field parasitic capacitor on the entry part of the device. Also, implanting the UIS was used in order to decrease the effect of parasitic bipolar junction transistor (BJT) of the VDMOS power transistor. The research tool used in this study was Silvaco software. By decreasing the transistor entry resistance in the optimized VDMOS structure, power losses and noise at the entry of the transistor were decreased, and, by increasing the breakdown voltage, the lifetime of the VDMOS transistor lifetime was increased, which resulted in increasing drain flow and decreasing Ron. This consequently resulted in enhancing the operation of high-frequency medical devices that use transistors, such as Radio Frequency (RF) and electrocardiograph machines.

  2. Optimization of Vertical Double-Diffused Metal-Oxide Semiconductor (VDMOS) Power Transistor Structure for Use in High Frequencies and Medical Devices.

    PubMed

    Farhadi, Rozita; Farhadi, Bita

    2014-01-01

    Power transistors, such as the vertical, double-diffused, metal-oxide semiconductor (VDMOS), are used extensively in the amplifier circuits of medical devices. The aim of this research was to construct a VDMOS power transistor with an optimized structure to enhance the operation of medical devices. First, boron was implanted in silicon by implanting unclamped inductive switching (UIS) and a Faraday shield. The Faraday shield was implanted in order to replace the gate-field parasitic capacitor on the entry part of the device. Also, implanting the UIS was used in order to decrease the effect of parasitic bipolar junction transistor (BJT) of the VDMOS power transistor. The research tool used in this study was Silvaco software. By decreasing the transistor entry resistance in the optimized VDMOS structure, power losses and noise at the entry of the transistor were decreased, and, by increasing the breakdown voltage, the lifetime of the VDMOS transistor lifetime was increased, which resulted in increasing drain flow and decreasing Ron. This consequently resulted in enhancing the operation of high-frequency medical devices that use transistors, such as Radio Frequency (RF) and electrocardiograph machines. PMID:25763152

  3. Black phosphorus nonvolatile transistor memory.

    PubMed

    Lee, Dain; Choi, Yongsuk; Hwang, Euyheon; Kang, Moon Sung; Lee, Seungwoo; Cho, Jeong Ho

    2016-04-28

    We demonstrated nanofloating gate transistor memory devices (NFGTMs) using mechanically-exfoliated few-layered black phosphorus (BP) channels and gold nanoparticle (AuNPs) charge trapping layers. The resulting BP-NFGTMs exhibited excellent memory performances, including the five-level data storage, large memory window (58.2 V), stable retention (10(4) s), and cyclic endurance (1000 cycles). PMID:27074903

  4. The four-gate transistor

    NASA Technical Reports Server (NTRS)

    Mojarradi, M. M.; Cristoveanu, S.; Allibert, F.; France, G.; Blalock, B.; Durfrene, B.

    2002-01-01

    The four-gate transistor or G4-FET combines MOSFET and JFET principles in a single SOI device. Experimental results reveal that each gate can modulate the drain current. Numerical simulations are presented to clarify the mechanisms of operation. The new device shows enhanced functionality, due to the combinatorial action of the four gates, and opens rather revolutionary applications.

  5. Characterization of SLUG microwave amplifiers

    NASA Astrophysics Data System (ADS)

    Hoi, I.-C.; Zhu, S.; Thorbeck, T.; McDermott, R.; Mutus, J.; Jeffrey, E.; Barends, R.; Chen, Y.; Roushan, P.; Fowler, A.; Sank, D.; White, T.; Campbell, B.; Chen, Z.; Chiaro, B.; Dunsworth, A.; Kelly, J.; Megrant, A.; Neill, C.; O'Malley, P. J. J.; Quintana, C.; Vainsencher, A.; Wenner, J.; Martinis, J. M.

    2015-03-01

    With the rapid growth of superconducting circuits quantum technology, a near quantum-limited amplifier at GHz frequency is needed to enable high fidelity measurements. We describe such an amplifier, the SQUID based, superconducting low inductance undulatory galvanometer (SLUG) amplifier. We measure the full scattering matrix of the SLUG. In particular, we measure both forward and reverse gain, as well as reflection. We see 15dB forward gain with added noise from one quanta to several quanta. The -1 dB compression point is around -95 dBm, about two orders of magnitude higher than that of typical Josephson parametric amplifiers. With these properties, SLUG is well suited for the high fidelity, simultaneous multiplexed readout of superconducting qubits.

  6. New Packaging for Amplifier Slabs

    SciTech Connect

    Riley, M.; Thorsness, C.; Suratwala, T.; Steele, R.; Rogowski, G.

    2015-03-18

    The following memo provides a discussion and detailed procedure for a new finished amplifier slab shipping and storage container. The new package is designed to maintain an environment of <5% RH to minimize weathering.

  7. Amplifier arrays for CMB polarization

    NASA Technical Reports Server (NTRS)

    Gaier, Todd; Lawrence, Charles R.; Seiffert, Michael D.; Wells, Mary M.; Kangaslahti, Pekka; Dawson, Douglas

    2003-01-01

    Cryogenic low noise amplifier technology has been successfully used in the study of the cosmic microwave background (CMB). MMIC (Monolithic Millimeter wave Integrated Circuit) technology makes the mass production of coherent detection receivers feasible.

  8. Enhanced performance CCD output amplifier

    DOEpatents

    Dunham, Mark E.; Morley, David W.

    1996-01-01

    A low-noise FET amplifier is connected to amplify output charge from a che coupled device (CCD). The FET has its gate connected to the CCD in common source configuration for receiving the output charge signal from the CCD and output an intermediate signal at a drain of the FET. An intermediate amplifier is connected to the drain of the FET for receiving the intermediate signal and outputting a low-noise signal functionally related to the output charge signal from the CCD. The amplifier is preferably connected as a virtual ground to the FET drain. The inherent shunt capacitance of the FET is selected to be at least equal to the sum of the remaining capacitances.

  9. Single-electron differential-amplifier/inverter/non-inverter

    NASA Astrophysics Data System (ADS)

    Hung, K.-M.; Chen, C.-S.; Lin, T.-W.

    2006-07-01

    This work presents a single-electron differential amplifier (SEDA), inverter, and non-inverter based on the triple single-dopant quantum-dot (TSDQD) configuration, with new structures. The competition between the field-induced and confinement-related shifts in the wavefunction of the quantum dots yields a field-controllable spatial-displacement single-electron transistor. Deeper impurity levels in quantum dots promise a higher operating temperature and higher on/off current ratios. The I- V characteristics of the device, studied using the transfer Hamiltonian approach (THA), show that the ratio of on/off currents is >80 000 and the voltage gain is >4 eV/Ry, where V is the applied voltage.

  10. Cryogenic ultra-low noise HEMT amplifiers board

    NASA Astrophysics Data System (ADS)

    de la Broïse, Xavier; Bounab, Ayoub

    2015-07-01

    High Electron Mobility Transistors (HEMTs), optimized by CNRS/LPN laboratory for ultra-low noise at a very low temperature, have demonstrated their capacity to be used in place of Si JFETs, when very high input impedance and working temperatures below 100 K are required. We have developed and tested simple amplifiers based only on this transistor technology, in order to work at a temperature as low as 1 K or less. They demonstrate at 4.2 K a typical noise of 1.6 nV/√{ Hz } at 100 Hz, 0.42 nV/√{ Hz } at 1 kHz and 0.32 nV/√{ Hz } at 10 kHz, with a gain of 50 and a power consumption of 1.4 mW per channel. Two boards have been designed for two different research applications: one for the readout of GMR magnetometers for medical and space applications, the other for search of weakly interacting massive particles (WIMPs) in Edelweiss experiment (HARD project).

  11. Single-transistor-clocked flip-flop

    DOEpatents

    Zhao, Peiyi; Darwish, Tarek; Bayoumi, Magdy

    2005-08-30

    The invention provides a low power, high performance flip-flop. The flip-flop uses only one clocked transistor. The single clocked transistor is shared by the first and second branches of the device. A pulse generator produces a clock pulse to trigger the flip-flop. In one preferred embodiment the device can be made as a static explicit pulsed flip-flop which employs only two clocked transistors.

  12. Coaxial inverted geometry transistor having buried emitter

    NASA Technical Reports Server (NTRS)

    Hruby, R. J.; Cress, S. B.; Dunn, W. R. (Inventor)

    1973-01-01

    The invention relates to an inverted geometry transistor wherein the emitter is buried within the substrate. The transistor can be fabricated as a part of a monolithic integrated circuit and is particularly suited for use in applications where it is desired to employ low actuating voltages. The transistor may employ the same doping levels in the collector and emitter, so these connections can be reversed.

  13. Principles of an atomtronic transistor

    NASA Astrophysics Data System (ADS)

    Caliga, Seth C.; Straatsma, Cameron J. E.; Zozulya, Alex A.; Anderson, Dana Z.

    2016-01-01

    A semiclassical formalism is used to investigate the transistor-like behavior of ultracold atoms in a triple-well potential. Atom current flows from the source well, held at fixed chemical potential and temperature, into an empty drain well. In steady-state, the gate well located between the source and drain is shown to acquire a well-defined chemical potential and temperature, which are controlled by the relative height of the barriers separating the three wells. It is shown that the gate chemical potential can exceed that of the source and have a lower temperature. In electronics terminology, the source-gate junction can be reverse-biased. As a result, the device exhibits regimes of negative resistance and transresistance, indicating the presence of gain. Given an external current input to the gate, transistor-like behavior is characterized both in terms of the current gain, which can be greater than unity, and the power output of the device.

  14. Black phosphorus nonvolatile transistor memory

    NASA Astrophysics Data System (ADS)

    Lee, Dain; Choi, Yongsuk; Hwang, Euyheon; Kang, Moon Sung; Lee, Seungwoo; Cho, Jeong Ho

    2016-04-01

    We demonstrated nanofloating gate transistor memory devices (NFGTMs) using mechanically-exfoliated few-layered black phosphorus (BP) channels and gold nanoparticle (AuNPs) charge trapping layers. The resulting BP-NFGTMs exhibited excellent memory performances, including the five-level data storage, large memory window (58.2 V), stable retention (104 s), and cyclic endurance (1000 cycles).We demonstrated nanofloating gate transistor memory devices (NFGTMs) using mechanically-exfoliated few-layered black phosphorus (BP) channels and gold nanoparticle (AuNPs) charge trapping layers. The resulting BP-NFGTMs exhibited excellent memory performances, including the five-level data storage, large memory window (58.2 V), stable retention (104 s), and cyclic endurance (1000 cycles). Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02078j

  15. Carrier and Envelope Frequency Measurements for Supply-Modulated Microwave Power Amplifiers

    NASA Astrophysics Data System (ADS)

    Schafer, Scott R.

    Transmitters for high peak-to-average power ratio communication are increasingly using supply modulation to improve efficiency. In addition to a dc component, the dynamic supply may contain ac components up to 500MHz. The signal envelope dynamic impedance of the supply terminal of a power amplifier (PA) is often unknown and available nonlinear transistor models are unable to predict dynamic low frequency effects required for design of wideband efficient supply modulators. This thesis investigates envelope frequency effects on nonlinear behavior of microwave transistors and PAs under supply-modulated conditions. A measurement setup is created to characterize multi-frequency large-signal excitation of GaN transistors and PAs at carrier frequencies in the 10GHz range with 1-500MHz low frequency excitation on the drain terminal. A novel method for multi-frequency analysis of nonlinear circuit components based on describing functions is developed. It is shown that the describing functions agree with simulation and measurements. In addition, the measurement setup is used to characterize the low frequency drain impedance of a MMIC PA when connected to a simple resonant supply modulator. The main motivation for this work is to obtain knowledge of the dynamic supply terminal in the low frequency regime (1-500MHz) that can enable power amplifier and supply modulator co-design for very broadband signals.

  16. Complementary junction heterostructure field-effect transistor

    DOEpatents

    Baca, A.G.; Drummond, T.J.; Robertson, P.J.; Zipperian, T.E.

    1995-12-26

    A complimentary pair of compound semiconductor junction heterostructure field-effect transistors and a method for their manufacture are disclosed. The p-channel junction heterostructure field-effect transistor uses a strained layer to split the degeneracy of the valence band for a greatly improved hole mobility and speed. The n-channel device is formed by a compatible process after removing the strained layer. In this manner, both types of transistors may be independently optimized. Ion implantation is used to form the transistor active and isolation regions for both types of complimentary devices. The invention has uses for the development of low power, high-speed digital integrated circuits. 10 figs.

  17. Complementary junction heterostructure field-effect transistor

    DOEpatents

    Baca, Albert G.; Drummond, Timothy J.; Robertson, Perry J.; Zipperian, Thomas E.

    1995-01-01

    A complimentary pair of compound semiconductor junction heterostructure field-effect transistors and a method for their manufacture are disclosed. The p-channel junction heterostructure field-effect transistor uses a strained layer to split the degeneracy of the valence band for a greatly improved hole mobility and speed. The n-channel device is formed by a compatible process after removing the strained layer. In this manner, both types of transistors may be independently optimized. Ion implantation is used to form the transistor active and isolation regions for both types of complimentary devices. The invention has uses for the development of low power, high-speed digital integrated circuits.

  18. Structured-gate organic field-effect transistors

    NASA Astrophysics Data System (ADS)

    Aljada, Muhsen; Pandey, Ajay K.; Velusamy, Marappan; Burn, Paul L.; Meredith, Paul; Namdas, Ebinazar B.

    2012-06-01

    We report the fabrication and electrical characteristics of structured-gate organic field-effect transistors consisting of a gate electrode patterned with three-dimensional pillars. The pillar gate electrode was over-coated with a gate dielectric (SiO2) and solution processed organic semiconductors producing both unipolar p-type and bipolar behaviour. We show that this new structured-gate architecture delivers higher source-drain currents, higher gate capacitance per unit equivalent linear channel area, and enhanced charge injection (electrons and/or holes) versus the conventional planar structure in all modes of operation. For the bipolar field-effect transistor (FET) the maximum source-drain current enhancements in p- and n-channel mode were >600% and 28%, respectively, leading to p and n charge mobilities with the same order of magnitude. Thus, we have demonstrated that it is possible to use the FET architecture to manipulate and match carrier mobilities of material combinations where one charge carrier is normally dominant. Mobility matching is advantageous for creating organic logic circuit elements such as inverters and amplifiers. Hence, the method represents a facile and generic strategy for improving the performance of standard organic semiconductors as well as new materials and blends.

  19. Reflex ring laser amplifier system

    SciTech Connect

    Summers, M.A.

    1983-08-31

    The invention is a method and apparatus for providing a reflex ring laser system for amplifying an input laser pulse. The invention is particularly useful in laser fusion experiments where efficient production of high-energy and high power laser pulses is required. The invention comprises a large aperture laser amplifier in an unstable ring resonator which includes a combination spatial filter and beam expander having a magnification greater than unity. An input pulse is injected into the resonator, e.g., through an aperture in an input mirror. The injected pulse passes through the amplifier and spatial filter/expander components on each pass around the ring. The unstable resonator is designed to permit only a predetermined number of passes before the amplified pulse exits the resonator. On the first pass through the amplifier, the beam fills only a small central region of the gain medium. On each successive pass, the beam has been expanded to fill the next concentric non-overlapping region of the gain medium.

  20. Cryogenic Preamplification of a Single-Electron-Transistor using a Silicon-Germanium Heterojunction-Bipolar-Transistor

    SciTech Connect

    Curry, Matthew J.; England, Troy Daniel; Bishop, Nathaniel; Ten Eyck, Gregory A.; Wendt, Joel R.; Pluym, Tammy; Lilly, Michael; Carr, Stephen M; Carroll, Malcolm S.

    2015-05-21

    We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10–100 larger than without the HBT at lower frequencies. Furthermore, the transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to without the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. We found that the circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.

  1. Cryogenic preamplification of a single-electron-transistor using a silicon-germanium heterojunction-bipolar-transistor

    SciTech Connect

    Curry, M. J.; England, T. D.; Bishop, N. C.; Ten-Eyck, G.; Wendt, J. R.; Pluym, T.; Lilly, M. P.; Carroll, M. S.; Carr, S. M.

    2015-05-18

    We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10–100 larger than without the HBT at lower frequencies. The transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to without the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. The circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.

  2. Cryogenic Preamplification of a Single-Electron-Transistor using a Silicon-Germanium Heterojunction-Bipolar-Transistor

    DOE PAGES

    Curry, Matthew J.; England, Troy Daniel; Bishop, Nathaniel; Ten Eyck, Gregory A.; Wendt, Joel R.; Pluym, Tammy; Lilly, Michael; Carr, Stephen M; Carroll, Malcolm S.

    2015-05-21

    We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10–100 larger than without the HBT at lower frequencies. Furthermore, the transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to withoutmore » the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. We found that the circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.« less

  3. Cryogenic preamplification of a single-electron-transistor using a silicon-germanium heterojunction-bipolar-transistor

    NASA Astrophysics Data System (ADS)

    Curry, M. J.; England, T. D.; Bishop, N. C.; Ten-Eyck, G.; Wendt, J. R.; Pluym, T.; Lilly, M. P.; Carr, S. M.; Carroll, M. S.

    2015-05-01

    We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10-100 larger than without the HBT at lower frequencies. The transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to without the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. The circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.

  4. Radio astronomy ultra-low-noise amplifier for operation at 91 cm wavelength in high RFI environment

    NASA Astrophysics Data System (ADS)

    Korolev, A. M.; Zakharenko, V. V.; Ulyanov, O. M.

    2016-02-01

    An ultra-low-noise input amplifier intended for a use in a radio telescope operating at 91 cm wavelength is presented. The amplifier noise temperatures are 12.8 ± 1.5 and 10.0 ± 1.5 K at ambient temperatures of 293 and 263 K respectively. The amplifier does not require cryogenic cooling. It can be quickly put in operation thus shortening losses in the telescope observation time. High linearity of the amplifier (output power at 1 dB gain compression P1dB ≥ 22 dBm, output third order intercept point OIP3 ≥ 37 dBm) enables the telescope operation in highly urbanized and industrialized regions. To obtain low noise characteristics along with high linearity, high-electron-mobility field-effect transistors were used in parallel in the circuit developed. The transistors used in the amplifier are cost-effective and commercially available. The circuit solution is recommended for similar devices working in ultra-high frequency band.

  5. T-shaped emitter metal heterojunction bipolar transistors for submillimeter wave applications

    NASA Technical Reports Server (NTRS)

    Fung, Andy; Samoska, Lorene; Velebir, Jim; Siege, Peter; Rodwell, Mark; Paidi, Vamsi; Griffth, Zach; Urteaga, Miguel; Malik, Roger

    2004-01-01

    We report on the development of submillimeter wave transistors at JPL. The goal of the effort is to produce advance-reliable high frequency and high power amplifiers, voltage controlled oscillators, active multipliers, and high-speed mixed-signal circuits for space borne applications. The technology in development to achieve this is based on the Indium Phosphide (InP) Heterojunction Bipolar Transistor (HBT). The HBT is well suited for high speed, high power and uniform (across wafer) performance, due to the ability to tailor the material structure that electrons traverse through by well-controlled epitaxial growth methods. InP with its compatible lattice matched alloys such as indium gallium arsenide (InGaAs) and indium aluminium arsenide (InAlAs) provides for high electron velocities and high voltage breakdown capabilities. The epitaxial methods for this material system are fairly mature, however the implementation of high performance and reliable transistors are still under development by many laboratories. Our most recently fabricated, second generation mesa HBTs at JPL have extrapolated current gain cutoff frequency (FJ of 142GHz and power gain cutoff frequency (Fm,) of approximately 160GHz. This represents a 13% and 33% improvement of Ft and F, respectively, compared to the first generation mesa HBTs [l]. Analysis based on the University of California, Santa Barbara (UCSB) device model, RF device characteristics can be significantly improved by reducing base contact resistance and base metal contact width. We will describe our effort towards increasing transistor performance and yield.

  6. Laser system using regenerative amplifier

    DOEpatents

    Emmett, J.L.

    1980-03-04

    High energy laser system is disclosed using a regenerative amplifier, which relaxes all constraints on laser components other than the intrinsic damage level of matter, so as to enable use of available laser system components. This can be accomplished by use of segmented components, spatial filters, at least one amplifier using solid state or gaseous media, and separated reflector members providing a long round trip time through the regenerative cavity, thereby allowing slower switching and adequate time to clear the spatial filters, etc. The laser system simplifies component requirements and reduces component cost while providing high energy output. 10 figs.

  7. Laser system using regenerative amplifier

    DOEpatents

    Emmett, John L. [Pleasanton, CA

    1980-03-04

    High energy laser system using a regenerative amplifier, which relaxes all constraints on laser components other than the intrinsic damage level of matter, so as to enable use of available laser system components. This can be accomplished by use of segmented components, spatial filters, at least one amplifier using solid state or gaseous media, and separated reflector members providing a long round trip time through the regenerative cavity, thereby allowing slower switching and adequate time to clear the spatial filters, etc. The laser system simplifies component requirements and reduces component cost while providing high energy output.

  8. Coherent amplified optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Rao, Bin; Chen, Zhongping

    2007-07-01

    A technique to improve the signal-to-noise ratio (SNR) of a high speed 1300 nm swept source optical coherence tomography (SSOCT) system was demonstrated. A semiconductor optical amplifier (SOA) was employed in the sample arm to coherently amplify the weak light back-scattered from sample tissue without increasing laser power illuminated on the sample. The image quality improvement was visualized and quantified by imaging the anterior segment of a rabbit eye at imaging speed of 20,000 A-lines per second. The theory analysis of SNR gain is given followed by the discussion on the technologies that can further improve the SNR gain.

  9. Amplified gigabit PON systems [Invited

    NASA Astrophysics Data System (ADS)

    Suzuki, Ken-Ichi; Fukada, Youichi; Nesset, Derek; Davey, Russell

    2007-05-01

    We describe how a passive optical network (PON) extender box can be implemented at standard PON wavelengths (1310 and 1490nm) using either optical fiber amplifiers (praseodymium and thulium) or semiconductor optical amplifiers to further increase the physical reach and split of a current standardized PON system such as a G-PON or GE-PON. The transparency to PON protocol of this approach means no changes to the existing standards are required. This is attractive as operators and vendors are keen to fully exploit the investment made in current PON standards.

  10. Design of Low-Noise Output Amplifiers for P-channel Charge-Coupled Devices Fabricated on High-Resistivity Silicon

    SciTech Connect

    Haque, S; Frost, F Dion R.; Groulx, R; Holland, S E; Karcher, A; Kolbe, W F; Roe, N A; Wang, G; Yu, Y

    2011-12-22

    We describe the design and optimization of low-noise, single-stage output amplifiers for p-channel charge-coupled devices (CCDs) used for scientific applications in astronomy and other fields. The CCDs are fabricated on high-resistivity, 4000–5000 -cm, n-type silicon substrates. Single-stage amplifiers with different output structure designs and technologies have been characterized. The standard output amplifier is designed with an n{sup +} polysilicon gate that has a metal connection to the sense node. In an effort to lower the output amplifier readout noise by minimizing the capacitance seen at the sense node, buried-contact technology has been investigated. In this case, the output transistor has a p{sup +} polysilicon gate that connects directly to the p{sup +} sense node. Output structures with buried-contact areas as small as 2 μm × 2 μm are characterized. In addition, the geometry of the source-follower transistor was varied, and we report test results on the conversion gain and noise of the various amplifier structures. By use of buried-contact technology, better amplifier geometry, optimization of the amplifier biases and improvements in the test electronics design, we obtain a 45% reduction in noise, corresponding to 1.7 e{sup -} rms at 70 kpixels/sec.

  11. Controlling Transistor Temperature During Burn-In

    NASA Technical Reports Server (NTRS)

    Scott, B. C.

    1986-01-01

    Boiling refrigerant provides simple temperature control for newly manufactured power transistors. Heat-transfer liquid is Fluorinert FC-77 (or equivalent). Liquid boils at 100 degrees C, which is specified temperature at which transistor cases should be maintained during burn-in with this technique.

  12. A hybrid nanomemristor/transistor logic circuit capable of self-programming.

    PubMed

    Borghetti, Julien; Li, Zhiyong; Straznicky, Joseph; Li, Xuema; Ohlberg, Douglas A A; Wu, Wei; Stewart, Duncan R; Williams, R Stanley

    2009-02-10

    Memristor crossbars were fabricated at 40 nm half-pitch, using nanoimprint lithography on the same substrate with Si metal-oxide-semiconductor field effect transistor (MOS FET) arrays to form fully integrated hybrid memory resistor (memristor)/transistor circuits. The digitally configured memristor crossbars were used to perform logic functions, to serve as a routing fabric for interconnecting the FETs and as the target for storing information. As an illustrative demonstration, the compound Boolean logic operation (A AND B) OR (C AND D) was performed with kilohertz frequency inputs, using resistor-based logic in a memristor crossbar with FET inverter/amplifier outputs. By routing the output signal of a logic operation back onto a target memristor inside the array, the crossbar was conditionally configured by setting the state of a nonvolatile switch. Such conditional programming illuminates the way for a variety of self-programmed logic arrays, and for electronic synaptic computing.

  13. PASOTRON{trademark} amplifier experiments

    SciTech Connect

    Ponti, E.S.; Goebel, D.M.; Feicht, J.R.; Santoru, J.; Eisenhart, R.L.

    1995-11-01

    Preliminary experimental studies are reported of an L-Band amplifier based on Hughes` Plasma-Assisted, Slow-Wave Oscillator (PASOTRON) technology. The amplifier system utilizes a hollow-cathode-plasma electron-gun, and a plasma-filled Slow-Wave Structure (SWS) to produce {>=} 100-{micro}sec-long, 50 to 75-kV, 30 to 100-A electron-beam pulses that propagate in a plasma channel without the use of any externally applied axial magnetic field. The electron-beam pulse coincides with a 100-{micro}sec-long RF drive signal provided by a 2.6-kW TWT, which is coupled into the amplifier upstream of the SWS. The SWS consists of a ring-bar design which is novel to the PASOTRON family of devices and is used for its short length compared to a helix. Simulations on HP`s High Frequency Structure Simulator were used to optimize the ring-bar SWS. Preliminary data are reported showing the new L-Band amplifiers gain, power, efficiency, and bandwidth. Methods of eliminating a Backward Wave Oscillation (BWO), which was found to limit the performance of the tube, are also presented.

  14. The School as an Amplifier.

    ERIC Educational Resources Information Center

    Vincent, William S.

    1966-01-01

    This paper attempts to show that adaptation of mathematics to the input-output model of the school can provide powerful assistance in the measurement and analysis of school quality and its determinants. The mathematical relationship described here relates an educational model to the field of electronics. More specifically, the amplifier, a device…

  15. Magnetoamplification in a bipolar magnetic junction transistor.

    PubMed

    Rangaraju, N; Peters, J A; Wessels, B W

    2010-09-10

    We have demonstrated the first bipolar magnetic junction transistor using a dilute magnetic semiconductor. For an InMnAs p-n-p transistor magnetoamplification is observed at room temperature. The observed magnetoamplification is attributed to the magnetoresistance of the magnetic semiconductor InMnAs heterojunction. The magnetic field dependence of the transistor characteristics confirm that the magnetoamplification results from the junction magnetoresistance. To describe the experimentally observed transistor characteristics, we propose a modified Ebers-Moll model that includes a series magnetoresistance attributed to spin-selective conduction. The capability of magnetic field control of the amplification in an all-semiconductor transistor at room temperature potentially enables the creation of new computer logic architecture where the spin of the carriers is utilized.

  16. Universal power transistor base drive control unit

    DOEpatents

    Gale, Allan R.; Gritter, David J.

    1988-01-01

    A saturation condition regulator system for a power transistor which achieves the regulation objectives of a Baker clamp but without dumping excess base drive current into the transistor output circuit. The base drive current of the transistor is sensed and used through an active feedback circuit to produce an error signal which modulates the base drive current through a linearly operating FET. The collector base voltage of the power transistor is independently monitored to develop a second error signal which is also used to regulate base drive current. The current-sensitive circuit operates as a limiter. In addition, a fail-safe timing circuit is disclosed which automatically resets to a turn OFF condition in the event the transistor does not turn ON within a predetermined time after the input signal transition.

  17. Universal power transistor base drive control unit

    DOEpatents

    Gale, A.R.; Gritter, D.J.

    1988-06-07

    A saturation condition regulator system for a power transistor is disclosed which achieves the regulation objectives of a Baker clamp but without dumping excess base drive current into the transistor output circuit. The base drive current of the transistor is sensed and used through an active feedback circuit to produce an error signal which modulates the base drive current through a linearly operating FET. The collector base voltage of the power transistor is independently monitored to develop a second error signal which is also used to regulate base drive current. The current-sensitive circuit operates as a limiter. In addition, a fail-safe timing circuit is disclosed which automatically resets to a turn OFF condition in the event the transistor does not turn ON within a predetermined time after the input signal transition. 2 figs.

  18. New Insights into Fully-Depleted SOI Transistor Response During Total-Dose Irradiation

    SciTech Connect

    BURNS,J.A.; DODD,PAUL E.; KEAST,C.L.; SCHWANK,JAMES R.; SHANEYFELT,MARTY R.; WYATT,P.W.

    1999-09-14

    Previous work showed the possible existence of a total-dose latch effect in fully-depleted SOI transistors that could severely limit the radiation hardness of SOI devices. Other work showed that worst-case bias configuration during irradiation was the transmission gate bias configuration. In this work we further explore the effects of total-dose ionizing irradiation on fully-depleted SOI transistors. Closed-geometry and standard transistors fabricated in two fully-depleted processes were irradiated with 10-keV x rays. Our results show no evidence for a total-dose latch effect as proposed by others. Instead, in absence of parasitic trench sidewall leakage, our data suggests that the increase in radiation-induced leakage current is caused by positive charge trapping in the buried oxide inverting the back-channel interface. At moderate levels of trapped charge, the back-channel interface is slightly inverted causing a small leakage current to flow. This leakage current is amplified to considerably higher levels by impact ionization. Because the back-channel interface is in weak inversion, the top-gate bias can modulate the back-channel interface and turn the leakage current off at large, negative voltage levels. At high levels of trapped charge, the back-channel interface is fully inverted and the gate bias has little effect on leakage current. However, it is likely that this current also is amplified by impact ionization. For these transistors, the worst-case bias configuration was determined to be the ''ON'' bias configuration. These results have important implication on hardness assurance.

  19. Highly Efficient Amplifier for Ka-Band Communications

    NASA Technical Reports Server (NTRS)

    1996-01-01

    An amplifier developed under a Small Business Innovation Research (SBIR) contract will have applications for both satellite and terrestrial communications. This power amplifier uses an innovative series bias arrangement of active devices to achieve over 40-percent efficiency at Ka-band frequencies with an output power of 0.66 W. The amplifier is fabricated on a 2.0- by 3.8-square millimeter chip through the use of Monolithic Microwave Integrated Circuit (MMIC) technology, and it uses state-of-the-art, Pseudomorphic High-Electron-Mobility Transistor (PHEMT) devices. Although the performance of the MMIC chip depends on these high-performance devices, the real innovations here are a unique series bias scheme, which results in a high-voltage chip supply, and careful design of the on-chip planar output stage combiner. This design concept has ramifications beyond the chip itself because it opens up the possibility of operation directly from a satellite power bus (usually 28 V) without a dc-dc converter. This will dramatically increase the overall system efficiency. Conventional microwave power amplifier designs utilize many devices all connected in parallel from the bias supply. This results in a low-bias voltage, typically 5 V, and a high bias current. With this configuration, substantial I(sup 2) R losses (current squared times resistance) may arise in the system bias-distribution network. By placing the devices in a series bias configuration, the total current is reduced, leading to reduced distribution losses. Careful design of the on-chip planar output stage power combiner is also important in minimizing losses. Using these concepts, a two-stage amplifier was designed for operation at 33 GHz and fabricated in a standard MMIC foundry process with 0.20-m PHEMT devices. Using a 20-V bias supply, the amplifier achieved efficiencies of over 40 percent with an output power of 0.66 W and a 16-dB gain over a 2-GHz bandwidth centered at 33 GHz. With a 28-V bias, a power

  20. Low Cost RF Amplifier for Community TV

    NASA Astrophysics Data System (ADS)

    Ch, Syafaruddin; Sasongko, Sudi Mariyanto Al; Made Budi Suksmadana, I.; Mustiko Okta Muvianto, Cahyo; Ariessaputra, Suthami

    2016-01-01

    he capability of television to deliver audio video makes this media become the most effective method to spread information. This paper presents an experiment of RF amplifier design having low-cost design and providing sufficient RF power particularly for community television. The RF amplifier consists of two stages of amplifier. The first stage amplifier was used to leverage output of TV modulator from 11dBm to enable to drive next stage amplifier. CAD simulation and fabrication were run to reach optimum RF amplifier design circuit. The associated circuit was made by determining stability circle, stability gain, and matching impedance. Hence, the average power of first stage RF amplifier was 24.68dBm achieved. The second stage used RF modules which was ready match to 50 ohm for both input and output port. The experiment results show that the RF amplifier may operate at frequency ranging from 174 to 230MHz. The average output power of the 2nd stage amplifier was 33.38 Watt with the overall gain of 20.54dB. The proposed RF amplifier is a cheap way to have a stable RF amplifier for community TV. The total budget for the designed RF amplifier is only a 1/5 compared to local design of final TV amplifier.

  1. Voltage regulator for battery power source. [using a bipolar transistor

    NASA Technical Reports Server (NTRS)

    Black, J. M. (Inventor)

    1979-01-01

    A bipolar transistor in series with the battery as the control element also in series with a zener diode and a resistor is used to maintain a predetermined voltage until the battery voltage decays to very nearly the predetermined voltage. A field effect transistor between the base of the bipolar transistor and a junction between the zener diode and resistor regulates base current of the bipolar transistor, thereby regulating the conductivity of the bipolar transistor for control of the output voltage.

  2. Electrical coupling between cells and graphene transistors.

    PubMed

    Hess, Lucas H; Becker-Freyseng, Christoph; Wismer, Michael S; Blaschke, Benno M; Lottner, Martin; Rolf, Felix; Seifert, Max; Garrido, Jose A

    2015-04-01

    In this work, both experimental data and a model are presented on the coupling between living cells and graphene solution-gated field-effect transistors. Modified HEK 293 cells are successfully cultured on graphene transistor arrays and electrically accessed by the patch clamp method. Transistor recordings are presented, showing the opening and closing of voltage-gated potassium ion channels in the cell membrane. The experimental data is compared with the broadly used standard point-contact model. The ion dynamics in the cell-transistor cleft are analyzed to account for the differences between the model and the experimental data revealing a significant increase in the total ionic strength in the cleft. In order to describe the influence of the ion concentration resulting from the cell activity, the ion-sensitivity of graphene solution-gated field-effect transistors is investigated experimentally and modelled by considering the screening effect of the ions on the surface potential at the graphene/electrolyte interface. Finally, the model of the cell-transistor coupling is extended to include the effect of ion accumulation and ion sensitivity. The experimental data shows a very good agreement with this extended model, emphasizing the importance of considering the ion concentration in the cleft to properly understand the cell-transistor coupling.

  3. High-performance vertical organic transistors.

    PubMed

    Kleemann, Hans; Günther, Alrun A; Leo, Karl; Lüssem, Björn

    2013-11-11

    Vertical organic thin-film transistors (VOTFTs) are promising devices to overcome the transconductance and cut-off frequency restrictions of horizontal organic thin-film transistors. The basic physical mechanisms of VOTFT operation, however, are not well understood and VOTFTs often require complex patterning techniques using self-assembly processes which impedes a future large-area production. In this contribution, high-performance vertical organic transistors comprising pentacene for p-type operation and C60 for n-type operation are presented. The static current-voltage behavior as well as the fundamental scaling laws of such transistors are studied, disclosing a remarkable transistor operation with a behavior limited by injection of charge carriers. The transistors are manufactured by photolithography, in contrast to other VOTFT concepts using self-assembled source electrodes. Fluorinated photoresist and solvent compounds allow for photolithographical patterning directly and strongly onto the organic materials, simplifying the fabrication protocol and making VOTFTs a prospective candidate for future high-performance applications of organic transistors. PMID:23637074

  4. Does surface roughness amplify wetting?

    SciTech Connect

    Malijevský, Alexandr

    2014-11-14

    Any solid surface is intrinsically rough on the microscopic scale. In this paper, we study the effect of this roughness on the wetting properties of hydrophilic substrates. Macroscopic arguments, such as those leading to the well-known Wenzel's law, predict that surface roughness should amplify the wetting properties of such adsorbents. We use a fundamental measure density functional theory to demonstrate the opposite effect from roughness for microscopically corrugated surfaces, i.e., wetting is hindered. Based on three independent analyses we show that microscopic surface corrugation increases the wetting temperature or even makes the surface hydrophobic. Since for macroscopically corrugated surfaces the solid texture does indeed amplify wetting there must exist a crossover between two length-scale regimes that are distinguished by opposite response on surface roughening. This demonstrates how deceptive can be efforts to extend the thermodynamical laws beyond their macroscopic territory.

  5. The novel Light Amplifier concept

    NASA Astrophysics Data System (ADS)

    Ferenc, Daniel; Kranich, Daniel; Laille, Alvin; Lorenz, Eckart

    2006-11-01

    Photon detectors are indispensable in many areas of fundamental physics research, particularly in the emerging field of particle astrophysics, as well as in medical imaging and nuclear nonproliferation. For a significant progress in all these areas a new, inexpensive industrial mass-production photosensor technology is needed, in many cases with a very large active area. In order to reach that goal we have introduced several innovations. This paper focuses on one of them, the hemispherical Light Amplifier. We report on the proof of principle tests of the prototype derived from an existing QUASAR phototube and a new Geiger-mode avalanche photodiode. Our experiments prove that Light Amplifier concept presents a promising solution for a next-generation low-cost photon detector offering superior performance.

  6. Ambipolar MoTe2 transistors and their applications in logic circuits.

    PubMed

    Lin, Yen-Fu; Xu, Yong; Wang, Sheng-Tsung; Li, Song-Lin; Yamamoto, Mahito; Aparecido-Ferreira, Alex; Li, Wenwu; Sun, Huabin; Nakaharai, Shu; Jian, Wen-Bin; Ueno, Keiji; Tsukagoshi, Kazuhito

    2014-05-28

    We report ambipolar charge transport in α-molybdenum ditelluride (MoTe2 ) flakes, whereby the temperature dependence of the electrical characteristics was systematically analyzed. The ambipolarity of the charge transport originated from the formation of Schottky barriers at the metal/MoTe2 contacts. The Schottky barrier heights as well as the current on/off ratio could be modified by modulating the electrostatic fields of the back-gate voltage (Vbg) and drain-source voltage (Vds). Using these ambipolar MoTe2 transistors we fabricated complementary inverters and amplifiers, demonstrating their feasibility for future digital and analog circuit applications. PMID:24692079

  7. A better understanding of organic electrochemical transistors for biosensing applications (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Friedlein, Jacob T.; Malliaras, George G.; Shaheen, Sean E.; McLeod, Robert R.

    2015-10-01

    Due to their biocompatibility, high transconductance, and low operating voltages, organic electrochemical transistors (OECTs) are promising platforms for biosensing applications. They have been used for measuring enzymes such as glucose and lactate, detecting disruptions of epithelial cell integrity, and amplifying epileptic voltage signals in rat brains. Accelerating the development of OECTs in this diverse range of potential applications, and those unforeseen, requires continued investigation of the device physics and material properties. In this presentation, we will describe our work to better understand OECT behavior, and we will discuss how this understanding can be used to develop more effective biosensors.

  8. High power gas laser amplifier

    DOEpatents

    Leland, Wallace T.; Stratton, Thomas F.

    1981-01-01

    A high power output CO.sub.2 gas laser amplifier having a number of sections, each comprising a plurality of annular pumping chambers spaced around the circumference of a vacuum chamber containing a cold cathode, gridded electron gun. The electron beam from the electron gun ionizes the gas lasing medium in the sections. An input laser beam is split into a plurality of annular beams, each passing through the sections comprising one pumping chamber.

  9. 338-GHz Semiconductor Amplifier Module

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Gaier, Todd C.; Soria, Mary M.; Fung, King Man; Rasisic, Vesna; Deal, William; Leong, Kevin; Mei, Xiao Bing; Yoshida, Wayne; Liu, Po-Hsin; Uyeda, Jansen; Lai, Richard

    2010-01-01

    Research findings were reported from an investigation of new gallium nitride (GaN) monolithic millimeter-wave integrated circuit (MMIC) power amplifiers (PAs) targeting the highest output power and the highest efficiency for class-A operation in W-band (75-110 GHz). W-band PAs are a major component of many frequency multiplied submillimeter-wave LO signal sources. For spectrometer arrays, substantial W-band power is required due to the passive lossy frequency multipliers.

  10. High power regenerative laser amplifier

    DOEpatents

    Miller, John L.; Hackel, Lloyd A.; Dane, Clifford B.; Zapata, Luis E.

    1994-01-01

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

  11. High power regenerative laser amplifier

    DOEpatents

    Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

    1994-02-08

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

  12. Small and lightweight power amplifiers

    NASA Astrophysics Data System (ADS)

    Shams, Qamar A.; Barnes, Kevin N.; Fox, Robert L.; Moses, Robert W.; Bryant, Robert G.; Robinson, Paul C.; Shirvani, Mir

    2002-07-01

    The control of u wanted structural vibration is implicit in most of NASA's programs. Currently several approaches to control vibrations in large, lightweight, deployable structures and twin tail aircraft at high angles of attack are being evaluated. The Air Force has been examining a vertical tail buffet load alleviation system that can be integrated onboard an F/A-18 and flown. Previous wind tunnel and full-scale ground tests using distributed actuators have shown that the concept works; however, there is insufficient rom available onboard an F/A-18 to store current state-of- the-art system components such as amplifiers, DC-to-DC converter and a computer for performing vibration suppression. Sensor processing, power electronics, DC-to-DC converters, and control electronics that may be collocated with distributed actuators, are particularly desirable. Such electronic system would obviate the need for complex, centralized, control processing and power distribution components that will eliminate the weight associated with lengthy wiring and cabling networks. Several small and lightweight power amplifiers ranging from 300V pp to 650V pp have been designed using off the shelf components for different applications. In this paper, the design and testing of these amplifiers will be presented under various electrical loads.

  13. Pass-transistor very large scale integration

    NASA Technical Reports Server (NTRS)

    Maki, Gary K. (Inventor); Bhatia, Prakash R. (Inventor)

    2004-01-01

    Logic elements are provided that permit reductions in layout size and avoidance of hazards. Such logic elements may be included in libraries of logic cells. A logical function to be implemented by the logic element is decomposed about logical variables to identify factors corresponding to combinations of the logical variables and their complements. A pass transistor network is provided for implementing the pass network function in accordance with this decomposition. The pass transistor network includes ordered arrangements of pass transistors that correspond to the combinations of variables and complements resulting from the logical decomposition. The logic elements may act as selection circuits and be integrated with memory and buffer elements.

  14. Transistors using crystalline silicon devices on glass

    DOEpatents

    McCarthy, Anthony M.

    1995-01-01

    A method for fabricating transistors using single-crystal silicon devices on glass. This method overcomes the potential damage that may be caused to the device during high voltage bonding and employs a metal layer which may be incorporated as part of the transistor. This is accomplished such that when the bonding of the silicon wafer or substrate to the glass substrate is performed, the voltage and current pass through areas where transistors will not be fabricated. After removal of the silicon substrate, further metal may be deposited to form electrical contact or add functionality to the devices. By this method both single and gate-all-around devices may be formed.

  15. Three MMIC Amplifiers for the 120-to-200 GHz Frequency Band

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Schmitz, Adele

    2009-01-01

    Closely following the development reported in the immediately preceding article, three new monolithic microwave integrated circuit (MMIC) amplifiers that would operate in the 120-to-200-GHz frequency band have been designed and are under construction at this writing. The active devices in these amplifiers are InP high-electron-mobility transistors (HEMTs). These amplifiers (see figure) are denoted the LSLNA150, the LSA200, and the LSA185, respectively. Like the amplifiers reported in the immediately preceding article, the LSLNA150 (1) is intended to be a prototype of low-noise amplifiers (LNAs) to be incorporated into spaceborne instruments for sensing cosmic microwave background radiation and (2) has potential for terrestrial use in electronic test equipment, passive millimeter-wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The HEMTs in this amplifier were fabricated according to 0.08- m design rules of a commercial product line of InP HEMT MMICs at HRL Laboratories, LLC, with a gate geometry of 2 fingers, each 15 m wide. On the basis of computational simulations, this amplifier is designed to afford at least 15 dB of gain, with a noise figure of no more than about 6 dB, at frequencies from 120 to 160 GHz. The measured results of the amplifier are shown next to the chip photo, with a gain of 16 dB at 150 GHz. Noise figure work is ongoing. The LSA200 and the LSA185 are intended to be prototypes of transmitting power amplifiers for use at frequencies between about 180 and about 200 GHz. These amplifiers have also been fabricated according to rules of the aforesaid commercial product line of InP HEMT MMICs, except that the HEMTs in these amplifiers are characterized by a gate geometry of 4 fingers, each 37 m wide. The measured peak performance of the LSA200 is characterized by a gain of about 1.4 dB at a frequency of 190 GHz; the measured peak performance of the LSA185 is characterized by a gain of about 2

  16. Improved charge amplifier using hybrid hysteresis compensation

    NASA Astrophysics Data System (ADS)

    Amin-Shahidi, Darya; Trumper, David L.

    2013-08-01

    We present a novel charge amplifier, with a robust feedback circuit and a method for compensating piezoelectric actuator's hysteresis at low frequencies. The amplifier uses a modified feedback circuit which improves robustness to the addition of series load impedance such as in cabling. We also describe a hybrid hysteresis compensation method for enabling the charge amplifier to reduce hysteresis at low frequencies. Experimental results demonstrate the utility of the new amplifier design.

  17. Fabrication of Very High Efficiency 5.8 GHz Power Amplifiers using AlGaN HFETs on SiC Substrates for Wireless Power Transmission

    NASA Technical Reports Server (NTRS)

    Sullivan, Gerry

    2001-01-01

    For wireless power transmission using microwave energy, very efficient conversion of the DC power into microwave power is extremely important. Class E amplifiers have the attractive feature that they can, in theory, be 100% efficient at converting, DC power to RF power. Aluminum gallium nitride (AlGaN) semiconductor material has many advantageous properties, relative to silicon (Si), gallium arsenide (GaAs), and silicon carbide (SiC), such as a much larger bandgap, and the ability to form AlGaN/GaN heterojunctions. The large bandgap of AlGaN also allows for device operation at higher temperatures than could be tolerated by a smaller bandgap transistor. This could reduce the cooling requirements. While it is unlikely that the AlGaN transistors in a 5.8 GHz class E amplifier can operate efficiently at temperatures in excess of 300 or 400 C, AlGaN based amplifiers could operate at temperatures that are higher than a GaAs or Si based amplifier could tolerate. Under this program, AlGaN microwave power HFETs have been fabricated and characterized. Hybrid class E amplifiers were designed and modeled. Unfortunately, within the time frame of this program, good quality HFETs were not available from either the RSC laboratories or commercially, and so the class E amplifiers were not constructed.

  18. Flexible Low-power SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout

    NASA Astrophysics Data System (ADS)

    England, Troy; Lilly, Michael; Curry, Matthew; Carr, Stephen; Carroll, Malcolm

    Fast, low-power quantum state readout is one of many challenges facing quantum information processing. Single electron transistors (SETs) are potentially fast, sensitive detectors for performing spin readout of electrons bound to Si:P donors. From a circuit perspective, however, their output impedance and nonlinear conductance are ill suited to drive the parasitic capacitance of coaxial conductors used in cryogenic environments, necessitating a cryogenic amplification stage. We will introduce two new amplifier topologies that provide excellent gain versus power tradeoffs using silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs). The AC HBT allows in-situ adjustment of power dissipation during an experiment and can provide gain in the millikelvin temperature regime while dissipating less than 500 nW. The AC Current Amplifier maximizes gain at nearly 800 A/A. We will also show results of using these amplifiers with SETs at 4 K. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. Flexible Low-power SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout.

  19. NASA developments in solid state power amplifiers

    NASA Technical Reports Server (NTRS)

    Leonard, Regis F.

    1990-01-01

    Over the last ten years, NASA has undertaken an extensive program aimed at development of solid state power amplifiers for space applications. Historically, the program may be divided into three phases. The first efforts were carried out in support of the advanced communications technology satellite (ACTS) program, which is developing an experimental version of a Ka-band commercial communications system. These first amplifiers attempted to use hybrid technology. The second phase was still targeted at ACTS frequencies, but concentrated on monolithic implementations, while the current, third phase, is a monolithic effort that focusses on frequencies appropriate for other NASA programs and stresses amplifier efficiency. The topics covered include: (1) 20 GHz hybrid amplifiers; (2) 20 GHz monolithic MESFET power amplifiers; (3) Texas Instruments' (TI) 20 GHz variable power amplifier; (4) TI 20 GHz high power amplifier; (5) high efficiency monolithic power amplifiers; (6) GHz high efficiency variable power amplifier; (7) TI 32 GHz monolithic power amplifier performance; (8) design goals for Hughes' 32 GHz variable power amplifier; and (9) performance goals for Hughes' pseudomorphic 60 GHz power amplifier.

  20. Remote Acquisition Amplifier For 50-Ohm Cable

    NASA Technical Reports Server (NTRS)

    Amador, Jose J.

    1995-01-01

    Buffer-amplifier unit designed to drive 50-Ohm cables up to 100 ft. (30 m) long, compensating for attenuation in cables and enabling remote operation of oscilloscopes. Variable resistor provides for adjustment of gain of amplifier, such that overall gain from input terminals of amplifier to output end of cable set to unity.

  1. Low Noise Amplifiers for 140 Ghz Wide-Band Cryogenic Receivers

    NASA Technical Reports Server (NTRS)

    Larkoski, Patricia V.; Kangaslahti, Pekka; Samoska, Lorene; Lai, Richard; Sarkozy, Stephen

    2013-01-01

    We report S-parameter and noise measurements for three different Indium Phosphide 35-nanometer-gate-length High Electron Mobility Transistor (HEMT) Low Noise Amplifier (LNA) designs operating in the frequency range centered on 140 gigahertz. When packaged in a Waveguide Rectangular-6.1 waveguide housing, the LNAs have an average measured noise figure of 3.0 decibels - 3.6 decibels over the 122-170 gigahertz band. One LNA was cooled to 20 degrees Kelvin and a record low noise temperature of 46 Kelvin, or 0.64 decibels noise figure, was measured at 152 gigahertz. These amplifiers can be used to develop receivers for instruments that operate in the 130-170 gigahertz atmospheric window, which is an important frequency band for ground-based astronomy and millimeter-wave imaging applications.

  2. 2.4 GHz CMOS Power Amplifier with Mode-Locking Structure to Enhance Gain

    PubMed Central

    2014-01-01

    We propose a mode-locking method optimized for the cascode structure of an RF CMOS power amplifier. To maximize the advantage of the typical mode-locking method in the cascode structure, the input of the cross-coupled transistor is modified from that of a typical mode-locking structure. To prove the feasibility of the proposed structure, we designed a 2.4 GHz CMOS power amplifier with a 0.18 μm RFCMOS process for polar transmitter applications. The measured power added efficiency is 34.9%, while the saturated output power is 23.32 dBm. The designed chip size is 1.4 × 0.6 mm2. PMID:25045755

  3. Noise spectroscopy of polymer transistors

    NASA Astrophysics Data System (ADS)

    Harsh, Rishav; Narayan, K. S.

    2015-11-01

    Noise studies constitute an important approach to study polymer based field effect transistors (FETs) from the perspective of disorder physics as well as device application. The current fluctuations in an all organic solution-processable FET in different regimes of operation (I-V) are measured and analyzed. The intrinsic transport noise is sizable and readily observed in the current time series measurements. The ensuing current spectrum (SI(f)) exhibits a typical 1/f characteristics. It is observed that this noise amplitude scales with respect to current bias and indicative of mobility as well as number fluctuations at dielectric-semiconductor interface. FETs with leakage (lossy) dielectric layer indicate characteristic noise spectrum features which can serve as a diagnostic tool to monitor device stability.

  4. Logic gates based on ion transistors.

    PubMed

    Tybrandt, Klas; Forchheimer, Robert; Berggren, Magnus

    2012-01-01

    Precise control over processing, transport and delivery of ionic and molecular signals is of great importance in numerous fields of life sciences. Integrated circuits based on ion transistors would be one approach to route and dispense complex chemical signal patterns to achieve such control. To date several types of ion transistors have been reported; however, only individual devices have so far been presented and most of them are not functional at physiological salt concentrations. Here we report integrated chemical logic gates based on ion bipolar junction transistors. Inverters and NAND gates of both npn type and complementary type are demonstrated. We find that complementary ion gates have higher gain and lower power consumption, as compared with the single transistor-type gates, which imitates the advantages of complementary logics found in conventional electronics. Ion inverters and NAND gates lay the groundwork for further development of solid-state chemical delivery circuits. PMID:22643898

  5. Ultra-stable oscillator with complementary transistors

    NASA Technical Reports Server (NTRS)

    Kleinberg, L. L. (Inventor)

    1974-01-01

    A high frequency oscillator, having both good short and long term stability, is formed by including a piezoelectric crystal in the base circuit of a first bi-polar transistor circuit, the bi-polar transistor itself operated below its transitional frequency and having its emitter load chosen so that the input impedance, looking into the base thereof, exhibits a negative resistance in parallel with a capacitive reactance. Combined with this basic circuit is an auxiliary, complementary, second bi-polar transistor circuit of the same form with the piezoelectric crystal being common to both circuits. By this configuration small changes in quiescent current are substantially cancelled by opposite variations in the second bi-polar transistor circuit, thereby achieving from the oscillator a signal having its frequency of oscillation stable over long time periods as well as short time periods.

  6. Logic gates based on ion transistors

    NASA Astrophysics Data System (ADS)

    Tybrandt, Klas; Forchheimer, Robert; Berggren, Magnus

    2012-05-01

    Precise control over processing, transport and delivery of ionic and molecular signals is of great importance in numerous fields of life sciences. Integrated circuits based on ion transistors would be one approach to route and dispense complex chemical signal patterns to achieve such control. To date several types of ion transistors have been reported; however, only individual devices have so far been presented and most of them are not functional at physiological salt concentrations. Here we report integrated chemical logic gates based on ion bipolar junction transistors. Inverters and NAND gates of both npn type and complementary type are demonstrated. We find that complementary ion gates have higher gain and lower power consumption, as compared with the single transistor-type gates, which imitates the advantages of complementary logics found in conventional electronics. Ion inverters and NAND gates lay the groundwork for further development of solid-state chemical delivery circuits.

  7. Log amplifier with pole-zero compensation

    DOEpatents

    Brookshier, William

    1987-01-01

    A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifier circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedback loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point or pole is offset by a compensating break point or zero.

  8. Transistor package for high pressure applications

    NASA Technical Reports Server (NTRS)

    Zantos, P. J.

    1981-01-01

    TO63 transistor package can operate in hydraulic oil ar pressures of 200 psi or greater without leakage failure if it is reinforced by alumina disk brazed to cap and terminals. This inexpensive modification has been used successfully on power transistors in hydraulic circulating-pump assemblies for Space Shuttle orbiter and should be effective in other pressurized environments, such as in oil exploration equipment.

  9. Shaping Transistor Leads for Better Solder Joints

    NASA Technical Reports Server (NTRS)

    Mandel, H.; Dillon, J. D.

    1982-01-01

    Special lead-forming tool puts step in leads of microwave power transistors without damaging braze joints that fasten leads to package. Stepped leads are soldered to circuit boards more reliably than straight leads, and stress on brazes is relieved. Lead-forming hand-tool has two parts: a forming die and an actuator. Spring-loaded saddle is adjusted so that when transistor package is placed on it, leads rest on forming rails.

  10. HIGH AVERAGE POWER OPTICAL FEL AMPLIFIERS.

    SciTech Connect

    BEN-ZVI, ILAN, DAYRAN, D.; LITVINENKO, V.

    2005-08-21

    Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Linac which is under construction at Brookhaven National Laboratory's Collider-Accelerator Department.

  11. The Integration and Applications of Organic Thin Film Transistors and Ferroelectric Polymers

    NASA Astrophysics Data System (ADS)

    Hsu, Yu-Jen

    Organic thin film transistors and ferroelectric polymer (polyvinylidene difluoride) sheet material are integrated to form various sensors for stress/strain, acoustic wave, and Infrared (heat) sensing applications. Different from silicon-based transistors, organic thin film transistors can be fabricated and processed in room-temperature and integrated with a variety of substrates. On the other hand, polyvinylidene difluoride (PVDF) exhibits ferroelectric properties that are highly useful for sensor applications. The wide frequency bandwidth (0.001 Hz to 10 GHz), vast dynamic range (100n to 10M psi), and high elastic compliance (up to 3 percent) make PVDF a more suitable candidate over ceramic piezoelectric materials for thin and flexible sensor applications. However, the low Curie temperature may have impeded its integration with silicon technology. Organic thin film transistors, however, do not have the limitation of processing temperature, hence can serve as transimpedance amplifiers to convert the charge signal generated by PVDF into current signal that are more measurable and less affected by any downstream parasitics. Piezoelectric sensors are useful for a range of applications, but passive arrays suffer from crosstalk and signal attenuation which have complicated the development of array-based PVDF sensors. We have used organic field effect transistors, which are compatible with the low Curie temperature of a flexible piezoelectric polymer,PVDF, to monolithically fabricate transimpedance amplifiers directly on the sensor surface and convert the piezoelectric charge signal into a current signal which can be detected even in the presence of parasitic capacitances. The device couples the voltage generated by the PVDF film under strain into the gate of the organic thin film transistors (OFET) using an arrangement that allows the full piezoelectric voltage to couple to the channel, while also increasing the charge retention time. A bipolar detector is created by

  12. High temperature charge amplifier for geothermal applications

    DOEpatents

    Lindblom, Scott C.; Maldonado, Frank J.; Henfling, Joseph A.

    2015-12-08

    An amplifier circuit in a multi-chip module includes a charge to voltage converter circuit, a voltage amplifier a low pass filter and a voltage to current converter. The charge to voltage converter receives a signal representing an electrical charge and generates a voltage signal proportional to the input signal. The voltage amplifier receives the voltage signal from the charge to voltage converter, then amplifies the voltage signal by the gain factor to output an amplified voltage signal. The lowpass filter passes low frequency components of the amplified voltage signal and attenuates frequency components greater than a cutoff frequency. The voltage to current converter receives the output signal of the lowpass filter and converts the output signal to a current output signal; wherein an amplifier circuit output is selectable between the output signal of the lowpass filter and the current output signal.

  13. ULTRA-STABILIZED D. C. AMPLIFIER

    DOEpatents

    Hartwig, E.C.; Kuenning, R.W.; Acker, R.C.

    1959-02-17

    An improved circuit is described for stabilizing the drift and minimizing the noise and hum level of d-c amplifiers so that the output voltage will be zero when the input is zero. In its detailed aspects, the disclosed circuit incorporates a d-c amplifier having a signal input, a second input, and an output circuit coupled back to the first input of the amplifier through inverse feedback means. An electronically driven chopper having a pair of fixed contacts and a moveable contact alternately connects the two inputs of a difference amplifier to the signal input. The A. E. error signal produced in the difference amplifier is amplified, rectified, and applied to the second input of the amplifier as the d-c stabilizing voltage.

  14. Nondegenerate optical parametric chirped pulse amplifier

    DOEpatents

    Jovanovic, Igor; Ebbers, Christopher A.

    2005-03-22

    A system provides an input pump pulse and a signal pulse. A first dichroic beamsplitter is highly reflective for the input signal pulse and highly transmissive for the input pump pulse. A first optical parametric amplifier nonlinear crystal transfers part of the energy from the input pump pulse to the input signal pulse resulting in a first amplified signal pulse and a first depleted pump pulse. A second dichroic beamsplitter is highly reflective for the first amplified signal pulse and highly transmissive for the first depleted pump pulse. A second optical parametric amplifier nonlinear crystal transfers part of the energy from the first depleted pump pulse to the first amplified signal pulse resulting in a second amplified signal pulse and a second depleted pump pulse. A third dichroic beamsplitter receives the second amplified signal pulse and the second depleted pump pulse. The second depleted pump pulse is discarded.

  15. Sub-10 nm carbon nanotube transistor.

    PubMed

    Franklin, Aaron D; Luisier, Mathieu; Han, Shu-Jen; Tulevski, George; Breslin, Chris M; Gignac, Lynne; Lundstrom, Mark S; Haensch, Wilfried

    2012-02-01

    Although carbon nanotube (CNT) transistors have been promoted for years as a replacement for silicon technology, there is limited theoretical work and no experimental reports on how nanotubes will perform at sub-10 nm channel lengths. In this manuscript, we demonstrate the first sub-10 nm CNT transistor, which is shown to outperform the best competing silicon devices with more than four times the diameter-normalized current density (2.41 mA/μm) at a low operating voltage of 0.5 V. The nanotube transistor exhibits an impressively small inverse subthreshold slope of 94 mV/decade-nearly half of the value expected from a previous theoretical study. Numerical simulations show the critical role of the metal-CNT contacts in determining the performance of sub-10 nm channel length transistors, signifying the need for more accurate theoretical modeling of transport between the metal and nanotube. The superior low-voltage performance of the sub-10 nm CNT transistor proves the viability of nanotubes for consideration in future aggressively scaled transistor technologies.

  16. Charge amplifier with bias compensation

    DOEpatents

    Johnson, Gary W.

    2002-01-01

    An ion beam uniformity monitor for very low beam currents using a high-sensitivity charge amplifier with bias compensation. The ion beam monitor is used to assess the uniformity of a raster-scanned ion beam, such as used in an ion implanter, and utilizes four Faraday cups placed in the geometric corners of the target area. Current from each cup is integrated with respect to time, thus measuring accumulated dose, or charge, in Coulombs. By comparing the dose at each corner, a qualitative assessment of ion beam uniformity is made possible. With knowledge of the relative area of the Faraday cups, the ion flux and areal dose can also be obtained.

  17. Analog Pre-Distortion Linearizer Using Self Base Bias Controlled Amplifier

    NASA Astrophysics Data System (ADS)

    Shinjo, Shintaro; Mori, Kazutomi; Yamada, Keiki; Suematsu, Noriharu; Shimozawa, Mitsuhiro

    An analog pre-distortion linearizer employing a radio frequency (RF) transistor with a self base bias control circuit is proposed. The self base bias control circuit extracts the envelope from the modulated input RF signal of the RF transistor and automatically controls its base current according to the extracted envelope. As a result, the proposed linearizer realizes positive gain deviation at high input power level. By adding a resistor between the RF transistor and the self base bias control circuit, the negative gain deviation can be derived. The design of the proposed lineaizer is described with taking the envelope frequency response of the self base bias control circuit into consideration. The fabricated linearizer achieves the adjacent channel power leakage ratio (ACLR) improvement of 8.1dB for a 2GHz-band, 10W-class GaAs FET high-power amplifier (HPA) with negative gain deviation for W-CDMA base stations. It also achieves the ACLR improvement of 8.3dB for a LDMOS HPA with positive gain deviation for the same application.

  18. Updated design for a low-noise, wideband transimpedance photodiode amplifier

    SciTech Connect

    Paul, S. F.; Marsala, R.

    2006-10-15

    The high-speed rotation diagnostic developed for Columbia's HBT-EP tokamak requires a high quantum efficiency, very low drift detector/amplifier combination. An updated version of the circuit developed originally for the beam emission spectroscopy experiment on TFTR is being used. A low dark current (2 nA at 15 V bias), low input source capacitance (2 pF) FFD-040 N-type Si photodiode is operated in photoconductive mode. It has a quantum efficiency of 40% at the 468.6 nm (He II line that is being observed). A low-noise field-effect transistor (InterFET IFN152 with e{sub Na}=1.2 nV/{radical}Hz) is used to reduce the noise in the transimpedance preamplifier (A250 AMPTEK op-amp) and a very high speed (unity-gain bandwidth=200 MHz) voltage feedback amplifier (LM7171) is used to restore the frequency response up to 100 kHz. This type of detector/amplifier is photon-noise limited at this bandwidth for incident light with a power of >{approx}2 nW. The circuit has been optimized using SIMETRIX 4.0 SPICE software and a prototype circuit has been tested successfully. Though photomultipliers and avalanche photodiodes can detect much lower light levels, for light levels >2 nW and a 10 kHz bandwidth, this detector/amplifier combination is more sensitive because of the absence of excess (internally generated) noise.

  19. A compact rail-to-rail CMOS buffer amplifier with very low quiescent current

    NASA Astrophysics Data System (ADS)

    Arslan, Emre; Yıldız, Merih; Minaei, Shahram

    2015-06-01

    In this work, a very compact, rail-to-rail, high-speed buffer amplifier for liquid crystal display (LCD) applications is proposed. Compared to other buffer amplifiers, the proposed circuit has a very simple architecture, occupies a small number of transistors and also has a large driving capacity with very low quiescent current. It is composed of two complementary differential input stages to provide rail-to-rail driving capacity. The push-pull transistors are directly connected to the differential input stage, and the output is taken from an inverter. The proposed buffer circuit is laid out using Mentor Graphics IC Station layout editor using AMS 0.35 μm process parameters. It is shown by post-layout simulations that the proposed buffer can drive a 1 nF capacitive load within a small settling time under a full voltage swing, while drawing only 1.6 μA quiescent current from a 3.3 V power supply.

  20. 6H-SiC Transistor Integrated Circuits Demonstrating Prolonged Operation at 500 C

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Spry, David J.; Chen, Liang-Yu; Chang, Carl W.; Beheim, Glenn M.; Okojie, Robert S.; Evans, Laura J.; Meredith, Roger; Ferrier, Terry; Krasowski, Michael J.; Prokop, Norman F.

    2008-01-01

    The NASA Glenn Research Center is developing very high temperature semiconductor integrated circuits (ICs) for use in the hot sections of aircraft engines and for Venus exploration where ambient temperatures are well above the approximately 300 degrees Centigrade effective limit of silicon-on-insulator IC technology. In order for beneficial technology insertion to occur, such transistor ICs must be capable of prolonged operation in such harsh environments. This paper reports on the fabrication and long-term 500 degrees Centigrade operation of 6H-SiC integrated circuits based on epitaxial 6H-SiC junction field effect transistors (JFETs). Simple analog amplifier and digital logic gate ICs have now demonstrated thousands of hours of continuous 500 degrees Centigrade operation in oxidizing air atmosphere with minimal changes in relevant electrical parameters. Electrical characterization and modeling of transistors and circuits at temperatures from 24 degrees Centigrade to 500 degrees Centigrade is also described. Desired analog and digital IC functionality spanning this temperature range was demonstrated without changing the input signals or power supply voltages.

  1. Few-layer molybdenum disulfide transistors and circuits for high-speed flexible electronics.

    PubMed

    Cheng, Rui; Jiang, Shan; Chen, Yu; Liu, Yuan; Weiss, Nathan; Cheng, Hung-Chieh; Wu, Hao; Huang, Yu; Duan, Xiangfeng

    2014-10-08

    Two-dimensional layered materials, such as molybdenum disulfide, are emerging as an exciting material system for future electronics due to their unique electronic properties and atomically thin geometry. Here we report a systematic investigation of MoS2 transistors with optimized contact and device geometry, to achieve self-aligned devices with performance including an intrinsic gain over 30, an intrinsic cut-off frequency fT up to 42 GHz and a maximum oscillation frequency fMAX up to 50 GHz, exceeding the reported values for MoS2 transistors to date (fT~0.9 GHz, fMAX~1 GHz). Our results show that logic inverters or radio frequency amplifiers can be formed by integrating multiple MoS2 transistors on quartz or flexible substrates with voltage gain in the gigahertz regime. This study demonstrates the potential of two-dimensional layered semiconductors for high-speed flexible electronics.

  2. High power RF solid state power amplifier system

    NASA Technical Reports Server (NTRS)

    Sims, III, William Herbert (Inventor); Chavers, Donald Gregory (Inventor); Richeson, James J. (Inventor)

    2011-01-01

    A high power, high frequency, solid state power amplifier system includes a plurality of input multiple port splitters for receiving a high-frequency input and for dividing the input into a plurality of outputs and a plurality of solid state amplifier units. Each amplifier unit includes a plurality of amplifiers, and each amplifier is individually connected to one of the outputs of multiport splitters and produces a corresponding amplified output. A plurality of multiport combiners combine the amplified outputs of the amplifiers of each of the amplifier units to a combined output. Automatic level control protection circuitry protects the amplifiers and maintains a substantial constant amplifier power output.

  3. High-Performance Solid-State W-Band Power Amplifiers

    NASA Technical Reports Server (NTRS)

    Gaier, Todd; Samoska, Lorene; Wells, Mary; Ferber, Robert; Pearson, John; Campbell, April; Peralta, Alejandro; Swift, Gerald; Yocum, Paul; Chung, Yun

    2003-01-01

    The figure shows one of four solid-state power amplifiers, each capable of generating an output power greater than or equal to 240 mW over one of four overlapping frequency bands from 71 to 106 GHz. (The bands are 71 to 84, 80 to 92, 88 to 99, and 89 to 106 GHz.) The amplifiers are designed for optimum performance at a temperature of 130 K. These amplifiers were developed specifically for incorporation into frequency-multiplier chains in local oscillators in a low-noise, far-infrared receiving instrument to be launched into outer space to make astrophysical observations. The designs of these amplifiers may also be of interest to designers and manufacturers of terrestrial W-band communication and radar systems. Each amplifier includes a set of six high-electron-mobility transistor (HEMT) GaAs monolithic microwave integrated-circuit (MMIC) chips, microstrip cavities, and other components packaged in a housing made from A-40 silicon-aluminum alloy. This alloy was chosen because, for the original intended spacecraft application, it offers an acceptable compromise among the partially competing requirements for high thermal conductivity, low mass, and low thermal expansion. Problems that were solved in designing the amplifiers included designing connectors and packages to fit the available space; designing microstrip signal-power splitters and combiners; matching of impedances across the frequency bands; matching of the electrical characteristics of those chips installed in parallel power-combining arms; control and levelling of output power across the bands; and designing the MMICs, microstrips, and microstrip cavities to suppress tendencies toward oscillation in several modes, both inside and outside the desired frequency bands.

  4. A compact 10 kW, 476 MHz solid state radio frequency amplifier for pre-buncher cavity of free electron laser injector linear accelerator

    SciTech Connect

    Mohania, Praveen; Mahawar, Ashish; Shrivastava, Purushottam; Gupta, P. D.

    2013-09-15

    A 10 kW, 476 MHz, 0.1% duty cycle solid state RF amplifier system for driving sub-harmonic, pre-buncher cavity of IR-FEL injector LINAC, has been developed at RRCAT. The 10 kW power is achieved by combining output of eight 1400 W amplifier modules using 8-way planar corporate combiner. The solid state amplifier modules have been developed using 50 V RF LDMOS transistors which although meant for push-pull operation are being used in single ended configuration with matching circuit developed on a thin (25 mils), high dielectric constant (9.7), low loss microwave laminate with an aim to have a compact structure. Ease of fabrication, modularity, small size, and low cost are the important features of this design which could be used as a template for low duty cycle medium to high pulsed power UHF amplifier system.

  5. Analyses of Transistor Punchthrough Failures

    NASA Technical Reports Server (NTRS)

    Nicolas, David P.

    1999-01-01

    The failure of two transistors in the Altitude Switch Assembly for the Solid Rocket Booster followed by two additional failures a year later presented a challenge to failure analysts. These devices had successfully worked for many years on numerous missions. There was no history of failures with this type of device. Extensive checks of the test procedures gave no indication for a source of the cause. The devices were manufactured more than twenty years ago and failure information on this lot date code was not readily available. External visual exam, radiography, PEID, and leak testing were performed with nominal results Electrical testing indicated nearly identical base-emitter and base-collector characteristics (both forward and reverse) with a low resistance short emitter to collector. These characteristics are indicative of a classic failure mechanism called punchthrough. In failure analysis punchthrough refers to an condition where a relatively low voltage pulse causes the device to conduct very hard producing localized areas of thermal runaway or "hot spots". At one or more of these hot spots, the excessive currents melt the silicon. Heavily doped emitter material diffuses through the base region to the collector forming a diffusion pipe shorting the emitter to base to collector. Upon cooling, an alloy junction forms between the pipe and the base region. Generally, the hot spot (punch-through site) is under the bond and no surface artifact is visible. The devices were delidded and the internal structures were examined microscopically. The gold emitter lead was melted on one device, but others had anomalies in the metallization around the in-tact emitter bonds. The SEM examination confirmed some anomalies to be cosmetic defects while other anomalies were artifacts of the punchthrough site. Subsequent to these analyses, the contractor determined that some irregular testing procedures occurred at the time of the failures heretofore unreported. These testing

  6. Multistaged stokes injected Raman capillary waveguide amplifier

    DOEpatents

    Kurnit, Norman A.

    1980-01-01

    A multistaged Stokes injected Raman capillary waveguide amplifier for providing a high gain Stokes output signal. The amplifier uses a plurality of optically coupled capillary waveguide amplifiers and one or more regenerative amplifiers to increase Stokes gain to a level sufficient for power amplification. Power amplification is provided by a multifocused Raman gain cell or a large diameter capillary waveguide. An external source of CO.sub.2 laser radiation can be injected into each of the capillary waveguide amplifier stages to increase Raman gain. Devices for injecting external sources of CO.sub.2 radiation include: dichroic mirrors, prisms, gratings and Ge Brewster plates. Alternatively, the CO.sub.2 input radiation to the first stage can be coupled and amplified between successive stages.

  7. Indium foil with beryllia washer improves transistor heat dissipation

    NASA Technical Reports Server (NTRS)

    Hilliard, J.; John, J. E. A.

    1964-01-01

    Indium foil, used as an interface material in transistor mountings, greatly reduces the thermal resistance of beryllia washers. This method improves the heat dissipation of power transistors in a vacuum environment.

  8. Field effect transistors used as voltage controlled resistors

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Two new methods of incorporating field effect transistors into circuit designs have resulted in linear response of this type transistor over a wide range of controlled voltage levels. This increases its usefulness as a voltage-controlled resistor.

  9. Optical latches using optical amplifiers

    NASA Astrophysics Data System (ADS)

    Li, Wenbo; Hu, Hongyu; Dutta, Niloy K.

    2013-05-01

    Optical latches are important for a wide range of applications including communication systems, optical logic systems, optical random access memory (RAM) and encryption. All optical logic operations using quantum dot (QD) based semiconductor optical amplifier (SOA) and Mach-Zehnder interferometer (MZI) have been studied. The building block of an optical latch such as NAND gate has been fabricated and their operation experimentally demonstrated at ~ 80 GHz. A rate equation model has been developed for the QD-SOA-MZI and it has been used to analyze the Boolean logic operation. The model has been used to analyze the Set-Reset (S-R) latch and the D-Flip-Flop (DFF) devices. The DFF is the basic device for building larger logic circuits. The results show that the latches would work to speeds of ~ 250 Gb/s.

  10. Transverse pumped laser amplifier architecture

    SciTech Connect

    Bayramian, Andrew James; Manes, Kenneth R.; Deri, Robert; Erlandson, Alvin; Caird, John; Spaeth, Mary L.

    2015-05-19

    An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

  11. Locoregional MYCN-amplified neuroblastoma.

    PubMed

    Morales La Madrid, Andres; Volchenboum, Samuel; Gastier-Foster, Julie M; Pyatt, Robert; Liu, Don; Pytel, Peter; Lavarino, Cinzia; Rodriguez, Eva; Cohn, Susan L

    2012-10-01

    MYCN-amplification is strongly associated with other high-risk prognostic factors and poor outcome in neuroblastoma. Infrequently, amplification of MYCN has been identified in localized tumors with favorable biologic features. Outcome for these children is difficult to predict and optimal treatment strategies remain unclear. We report a 5-month-old who presented with an MYCN-amplified INSS stage 3, pelvic neuroblastoma. The tumor had favorable histology, hyperdiploidy, and lacked 1p36 and 11q23 aberrations. Although the patient met the criteria for high-risk neuroblastoma, because of the discordant prognostic markers we elected to treat her according to an intermediate-risk protocol. She remains event-free more than 18 months.

  12. Transverse pumped laser amplifier architecture

    DOEpatents

    Bayramian, Andrew James; Manes, Kenneth; Deri, Robert; Erlandson, Al; Caird, John; Spaeth, Mary

    2013-07-09

    An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

  13. Hydraulically amplified PZT mems actuator

    DOEpatents

    Miles, Robin R.

    2004-11-02

    A hydraulically amplified microelectromechanical systems actuator. A piece of piezoelectric material or stacked piezo bimorph is bonded or deposited as a thin film. The piece is operatively connected to a primary membrane. A reservoir is operatively connected to the primary membrane. The reservoir contains a fluid. A membrane is operatively connected to the reservoir. In operation, energizing the piezoelectric material causing the piezoelectric material to bow. Bowing of the piezoelectric material causes movement of the primary membrane. Movement of the primary membrane results in a force in being transmitted to the liquid in the reservoir. The force in the liquid causes movement of the membrane. Movement of the membrane results in an operating actuator.

  14. Ambipolar phosphorene field effect transistor.

    PubMed

    Das, Saptarshi; Demarteau, Marcel; Roelofs, Andreas

    2014-11-25

    In this article, we demonstrate enhanced electron and hole transport in few-layer phosphorene field effect transistors (FETs) using titanium as the source/drain contact electrode and 20 nm SiO2 as the back gate dielectric. The field effect mobility values were extracted to be ∼38 cm(2)/Vs for electrons and ∼172 cm(2)/Vs for the holes. On the basis of our experimental data, we also comprehensively discuss how the contact resistances arising due to the Schottky barriers at the source and the drain end effect the different regime of the device characteristics and ultimately limit the ON state performance. We also propose and implement a novel technique for extracting the transport gap as well as the Schottky barrier height at the metal-phosphorene contact interface from the ambipolar transfer characteristics of the phosphorene FETs. This robust technique is applicable to any ultrathin body semiconductor which demonstrates symmetric ambipolar conduction. Finally, we demonstrate a high gain, high noise margin, chemical doping free, and fully complementary logic inverter based on ambipolar phosphorene FETs.

  15. Graphene nanopore field effect transistors

    SciTech Connect

    Qiu, Wanzhi; Skafidas, Efstratios

    2014-07-14

    Graphene holds great promise for replacing conventional Si material in field effect transistors (FETs) due to its high carrier mobility. Previously proposed graphene FETs either suffer from low ON-state current resulting from constrained channel width or require complex fabrication processes for edge-defecting or doping. Here, we propose an alternative graphene FET structure created on intrinsic metallic armchair-edged graphene nanoribbons with uniform width, where the channel region is made semiconducting by drilling a pore in the interior, and the two ends of the nanoribbon act naturally as connecting electrodes. The proposed GNP-FETs have high ON-state currents due to seamless atomic interface between the channel and electrodes and are able to be created with arbitrarily wide ribbons. In addition, the performance of GNP-FETs can be tuned by varying pore size and ribbon width. As a result, their performance and fabrication process are more predictable and controllable in comparison to schemes based on edge-defects and doping. Using first-principle transport calculations, we show that GNP-FETs can achieve competitive leakage current of ∼70 pA, subthreshold swing of ∼60 mV/decade, and significantly improved On/Off current ratios on the order of 10{sup 5} as compared with other forms of graphene FETs.

  16. A correlated nickelate synaptic transistor.

    PubMed

    Shi, Jian; Ha, Sieu D; Zhou, You; Schoofs, Frank; Ramanathan, Shriram

    2013-01-01

    Inspired by biological neural systems, neuromorphic devices may open up new computing paradigms to explore cognition, learning and limits of parallel computation. Here we report the demonstration of a synaptic transistor with SmNiO₃, a correlated electron system with insulator-metal transition temperature at 130°C in bulk form. Non-volatile resistance and synaptic multilevel analogue states are demonstrated by control over composition in ionic liquid-gated devices on silicon platforms. The extent of the resistance modulation can be dramatically controlled by the film microstructure. By simulating the time difference between postneuron and preneuron spikes as the input parameter of a gate bias voltage pulse, synaptic spike-timing-dependent plasticity learning behaviour is realized. The extreme sensitivity of electrical properties to defects in correlated oxides may make them a particularly suitable class of materials to realize artificial biological circuits that can be operated at and above room temperature and seamlessly integrated into conventional electronic circuits. PMID:24177330

  17. A dc amplifier for nuclear particle measurement

    NASA Technical Reports Server (NTRS)

    Macnee, A. B.; Masnari, N. A.

    1978-01-01

    A monolithic preamplifier-postamplifier combination has been developed for use with solid state particle detectors. The direct coupled amplifiers employ interdigitated n-channel JFET's, diodes, and diffused resistors. The circuits developed demonstrate the feasibility of matching the performance of existing discrete component designs. The fabrication procedures for the monolithic amplifier fabrication are presented and the results of measurements on a limited number of sample amplifiers are given.

  18. Simulation of a regenerative MW FEL amplifier

    SciTech Connect

    Nguyen, R.T.; Colson, W.B.; Wong, R.K.; Sheffield, R.L.

    1997-08-01

    Both oscillator and regenerative amplifier configurations are being studied to optimize the design of a MW class FEL. The regenerative amplifier uses a longer undulator and relies on higher extraction efficiency to achieve high average power, whereas the oscillator is a more compact overall design requiring the transport of the high energy electron beam around bends for energy recovery. Using parameters extrapolated from the 1 kW LANL regenerative amplifier, simulations study the feasibility of achieving 1 MW average power.

  19. Thermal electron-tunneling devices as coolers and amplifiers.

    PubMed

    Su, Shanhe; Zhang, Yanchao; Chen, Jincan; Shih, Tien-Mo

    2016-02-19

    Nanoscale thermal systems that are associated with a pair of electron reservoirs have been previously studied. In particular, devices that adjust electron tunnels relatively to reservoirs' chemical potentials enjoy the novelty and the potential. Since only two reservoirs and one tunnel exist, however, designers need external aids to complete a cycle, rendering their models non-spontaneous. Here we design thermal conversion devices that are operated among three electron reservoirs connected by energy-filtering tunnels and also referred to as thermal electron-tunneling devices. They are driven by one of electron reservoirs rather than the external power input, and are equivalent to those coupling systems consisting of forward and reverse Carnot cycles with energy selective electron functions. These previously-unreported electronic devices can be used as coolers and thermal amplifiers and may be called as thermal transistors. The electron and energy fluxes of devices are capable of being manipulated in the same or oppsite directions at our disposal. The proposed model can open a new field in the application of nano-devices.

  20. A Highly Responsive Silicon Nanowire/Amplifier MOSFET Hybrid Biosensor

    PubMed Central

    Lee, Jieun; Jang, Jaeman; Choi, Bongsik; Yoon, Jinsu; Kim, Jee-Yeon; Choi, Yang-Kyu; Myong Kim, Dong; Hwan Kim, Dae; Choi, Sung-Jin

    2015-01-01

    This study demonstrates a hybrid biosensor comprised of a silicon nanowire (SiNW) integrated with an amplifier MOSFET to improve the current response of field-effect-transistor (FET)-based biosensors. The hybrid biosensor is fabricated using conventional CMOS technology, which has the potential advantage of high density and low noise performance. The biosensor shows a current response of 5.74 decades per pH for pH detection, which is 2.5 × 105 times larger than that of a single SiNW sensor. In addition, we demonstrate charged polymer detection using the biosensor, with a high current change of 4.5 × 105 with a 500 nM concentration of poly(allylamine hydrochloride). In addition, we demonstrate a wide dynamic range can be obtained by adjusting the liquid gate voltage. We expect that this biosensor will be advantageous and practical for biosensor applications which requires lower noise, high speed, and high density. PMID:26197105

  1. A Low Noise Amplifier for Neural Spike Recording Interfaces

    PubMed Central

    Ruiz-Amaya, Jesus; Rodriguez-Perez, Alberto; Delgado-Restituto, Manuel

    2015-01-01

    This paper presents a Low Noise Amplifier (LNA) for neural spike recording applications. The proposed topology, based on a capacitive feedback network using a two-stage OTA, efficiently solves the triple trade-off between power, area and noise. Additionally, this work introduces a novel transistor-level synthesis methodology for LNAs tailored for the minimization of their noise efficiency factor under area and noise constraints. The proposed LNA has been implemented in a 130 nm CMOS technology and occupies 0.053 mm-sq. Experimental results show that the LNA offers a noise efficiency factor of 2.16 and an input referred noise of 3.8 μVrms for 1.2 V power supply. It provides a gain of 46 dB over a nominal bandwidth of 192 Hz–7.4 kHz and consumes 1.92 μW. The performance of the proposed LNA has been validated through in vivo experiments with animal models. PMID:26437411

  2. Thermal electron-tunneling devices as coolers and amplifiers

    PubMed Central

    Su, Shanhe; Zhang, Yanchao; Chen, Jincan; Shih, Tien-Mo

    2016-01-01

    Nanoscale thermal systems that are associated with a pair of electron reservoirs have been previously studied. In particular, devices that adjust electron tunnels relatively to reservoirs’ chemical potentials enjoy the novelty and the potential. Since only two reservoirs and one tunnel exist, however, designers need external aids to complete a cycle, rendering their models non-spontaneous. Here we design thermal conversion devices that are operated among three electron reservoirs connected by energy-filtering tunnels and also referred to as thermal electron-tunneling devices. They are driven by one of electron reservoirs rather than the external power input, and are equivalent to those coupling systems consisting of forward and reverse Carnot cycles with energy selective electron functions. These previously-unreported electronic devices can be used as coolers and thermal amplifiers and may be called as thermal transistors. The electron and energy fluxes of devices are capable of being manipulated in the same or oppsite directions at our disposal. The proposed model can open a new field in the application of nano-devices. PMID:26893109

  3. Thermal electron-tunneling devices as coolers and amplifiers

    NASA Astrophysics Data System (ADS)

    Su, Shanhe; Zhang, Yanchao; Chen, Jincan; Shih, Tien-Mo

    2016-02-01

    Nanoscale thermal systems that are associated with a pair of electron reservoirs have been previously studied. In particular, devices that adjust electron tunnels relatively to reservoirs’ chemical potentials enjoy the novelty and the potential. Since only two reservoirs and one tunnel exist, however, designers need external aids to complete a cycle, rendering their models non-spontaneous. Here we design thermal conversion devices that are operated among three electron reservoirs connected by energy-filtering tunnels and also referred to as thermal electron-tunneling devices. They are driven by one of electron reservoirs rather than the external power input, and are equivalent to those coupling systems consisting of forward and reverse Carnot cycles with energy selective electron functions. These previously-unreported electronic devices can be used as coolers and thermal amplifiers and may be called as thermal transistors. The electron and energy fluxes of devices are capable of being manipulated in the same or oppsite directions at our disposal. The proposed model can open a new field in the application of nano-devices.

  4. Amplifier based broadband pixel for sub-millimeter wave imaging

    NASA Astrophysics Data System (ADS)

    Sarkozy, Stephen; Drewes, Jonathan; Leong, Kevin M. K. H.; Lai, Richard; Mei, X. B. (Gerry); Yoshida, Wayne; Lange, Michael D.; Lee, Jane; Deal, William R.

    2012-09-01

    Broadband sub-millimeter wave technology has received significant attention for potential applications in security, medical, and military imaging. Despite theoretical advantages of reduced size, weight, and power compared to current millimeter wave systems, sub-millimeter wave systems have been hampered by a fundamental lack of amplification with sufficient gain and noise figure properties. We report a broadband pixel operating from 300 to 340 GHz, biased off a single 2 V power supply. Over this frequency range, the amplifiers provide > 40 dB gain and <8 dB noise figure, representing the current state-of-art performance capabilities. This pixel is enabled by revolutionary enhancements to indium phosphide (InP) high electron mobility transistor technology, based on a sub-50 nm gate and indium arsenide composite channel with a projected maximum oscillation frequency fmax>1.0 THz. The first sub-millimeter wave-based images using active amplification are demonstrated as part of the Joint Improvised Explosive Device Defeat Organization Longe Range Personnel Imager Program. This development and demonstration may bring to life future sub-millimeter-wave and THz applications such as solutions to brownout problems, ultra-high bandwidth satellite communication cross-links, and future planetary exploration missions.

  5. Log amplifier with pole-zero compensation

    DOEpatents

    Brookshier, W.

    1985-02-08

    A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifer circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedstock loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point is offset by a compensating break point or zero.

  6. Class E/F switching power amplifiers

    NASA Technical Reports Server (NTRS)

    Hajimiri, Seyed-Ali (Inventor); Aoki, Ichiro (Inventor); Rutledge, David B. (Inventor); Kee, Scott David (Inventor)

    2004-01-01

    The present invention discloses a new family of switching amplifier classes called class E/F amplifiers. These amplifiers are generally characterized by their use of the zero-voltage-switching (ZVS) phase correction technique to eliminate of the loss normally associated with the inherent capacitance of the switching device as utilized in class-E amplifiers, together with a load network for improved voltage and current wave-shaping by presenting class-F.sup.-1 impedances at selected overtones and class-E impedances at the remaining overtones. The present invention discloses a several topologies and specific circuit implementations for achieving such performance.

  7. High Accuracy Transistor Compact Model Calibrations

    SciTech Connect

    Hembree, Charles E.; Mar, Alan; Robertson, Perry J.

    2015-09-01

    Typically, transistors are modeled by the application of calibrated nominal and range models. These models consists of differing parameter values that describe the location and the upper and lower limits of a distribution of some transistor characteristic such as current capacity. Correspond- ingly, when using this approach, high degrees of accuracy of the transistor models are not expected since the set of models is a surrogate for a statistical description of the devices. The use of these types of models describes expected performances considering the extremes of process or transistor deviations. In contrast, circuits that have very stringent accuracy requirements require modeling techniques with higher accuracy. Since these accurate models have low error in transistor descriptions, these models can be used to describe part to part variations as well as an accurate description of a single circuit instance. Thus, models that meet these stipulations also enable the calculation of quantifi- cation of margins with respect to a functional threshold and uncertainties in these margins. Given this need, new model high accuracy calibration techniques for bipolar junction transis- tors have been developed and are described in this report.

  8. Polyphosphonium-based ion bipolar junction transistors

    PubMed Central

    Gabrielsson, Erik O.; Berggren, Magnus

    2014-01-01

    Advancements in the field of electronics during the past few decades have inspired the use of transistors in a diversity of research fields, including biology and medicine. However, signals in living organisms are not only carried by electrons but also through fluxes of ions and biomolecules. Thus, in order to implement the transistor functionality to control biological signals, devices that can modulate currents of ions and biomolecules, i.e., ionic transistors and diodes, are needed. One successful approach for modulation of ionic currents is to use oppositely charged ion-selective membranes to form so called ion bipolar junction transistors (IBJTs). Unfortunately, overall IBJT device performance has been hindered due to the typical low mobility of ions, large geometries of the ion bipolar junction materials, and the possibility of electric field enhanced (EFE) water dissociation in the junction. Here, we introduce a novel polyphosphonium-based anion-selective material into npn-type IBJTs. The new material does not show EFE water dissociation and therefore allows for a reduction of junction length down to 2 μm, which significantly improves the switching performance of the ion transistor to 2 s. The presented improvement in speed as well the simplified design will be useful for future development of advanced iontronic circuits employing IBJTs, for example, addressable drug-delivery devices. PMID:25553192

  9. Polyphosphonium-based ion bipolar junction transistors.

    PubMed

    Gabrielsson, Erik O; Tybrandt, Klas; Berggren, Magnus

    2014-11-01

    Advancements in the field of electronics during the past few decades have inspired the use of transistors in a diversity of research fields, including biology and medicine. However, signals in living organisms are not only carried by electrons but also through fluxes of ions and biomolecules. Thus, in order to implement the transistor functionality to control biological signals, devices that can modulate currents of ions and biomolecules, i.e., ionic transistors and diodes, are needed. One successful approach for modulation of ionic currents is to use oppositely charged ion-selective membranes to form so called ion bipolar junction transistors (IBJTs). Unfortunately, overall IBJT device performance has been hindered due to the typical low mobility of ions, large geometries of the ion bipolar junction materials, and the possibility of electric field enhanced (EFE) water dissociation in the junction. Here, we introduce a novel polyphosphonium-based anion-selective material into npn-type IBJTs. The new material does not show EFE water dissociation and therefore allows for a reduction of junction length down to 2 μm, which significantly improves the switching performance of the ion transistor to 2 s. The presented improvement in speed as well the simplified design will be useful for future development of advanced iontronic circuits employing IBJTs, for example, addressable drug-delivery devices. PMID:25553192

  10. SEMICONDUCTOR DEVICES: Large signal RF power transmission characterization of InGaP HBT for RF power amplifiers

    NASA Astrophysics Data System (ADS)

    Lixin, Zhao; Zhi, Jin; Xinyu, Liu

    2010-01-01

    The large signal RF power transmission characteristics of an advanced InGaP HBT in an RF power amplifier are investigated and analyzed experimentally. The realistic RF powers reflected by the transistor, transmitted from the transistor and reflected by the load are investigated at small signal and large signal levels. The RF power multiple frequency components at the input and output ports are investigated at small signal and large signal levels, including their effects on RF power gain compression and nonlinearity. The results show that the RF power reflections are different between the output and input ports. At the input port the reflected power is not always proportional to input power level; at large power levels the reflected power becomes more serious than that at small signal levels, and there is a knee point at large power levels. The results also show the effects of the power multiple frequency components on RF amplification.

  11. Ping-pong auto-zero amplifier with glitch reduction

    DOEpatents

    Larson, Mark R.

    2008-01-22

    A ping-pong amplifier with reduced glitching is described. The ping-pong amplifier includes a nulling amplifier coupled to a switching network. The switching network is used to auto-zero a ping amplifier within a ping-pong amplifier. The nulling amplifier drives the output of a ping amplifier to a proper output voltage level during auto-zeroing of the ping amplifier. By being at a proper output voltage level, glitches associated with transitioning between a ping amplifier and a pong amplifier are reduced or eliminated.

  12. Self-protecting transistor oscillator for treating animal tissues

    DOEpatents

    Doss, James D.

    1980-01-01

    A transistor oscillator circuit wherein the load current applied to animal tissue treatment electrodes is fed back to the transistor. Removal of load is sensed to automatically remove feedback and stop oscillations. A thermistor on one treatment electrode senses temperature, and by means of a control circuit controls oscillator transistor current.

  13. Discrete transistor measuring and matching using a solid core oven.

    PubMed

    Inkinen, M; Mäkelä, K; Vuorela, T; Palovuori, K

    2013-03-01

    This paper presents transistor measurements done at a constant temperature. The aim in this research was to develop a reliable and repeatable method for measuring and searching transistor pairs with similar parameters, as in certain applications it is advantageous to use transistors from the same production batch due to the significant variability in batches from different manufacturers. Transistor manufacturing methods are well established, but due to the large variability in tolerance, not even transistors from the same manufacturing batch have identical properties. Transistors' electrical properties are also strongly temperature-dependent. Therefore, when measuring transistor properties, the temperature must be kept constant. For the measurement process, a solid-core oven providing stable temperature was implemented. In the oven, the base-to-emitter voltage (VBE) and DC-current gain (β) of 32 transistors could be measured simultaneously. The oven's temperature was controlled with a programmable thermostat, which allowed accurate constant temperature operation. The oven is formed by a large metal block with an individual chamber for each transistor to be measured. Isolation of individual transistors and the highly thermally conductive metal core structure prevent thermal coupling between transistors. The oven enables repeatable measurements, and thus measurements between different batches are comparable. In this research study, the properties of over 5000 transistors were measured and the variance of the aforementioned properties was analyzed.

  14. Bipolar-FET combinational power transistors for power conversion applications

    NASA Technical Reports Server (NTRS)

    Chen, D. Y.; Chin, S. A.

    1984-01-01

    Four bipolar-FET (field-effect transistor) combinational transistor configurations are compared from the application point of view. The configurations included are FET-Darlington (cascade), emitter-open switch (cascode), parallel configuration, and FET-gated bipolar transistors (FGT).

  15. Stretchable transistors with buckled carbon nanotube films as conducting channels

    DOEpatents

    Arnold, Michael S; Xu, Feng

    2015-03-24

    Thin-film transistors comprising buckled films comprising carbon nanotubes as the conductive channel are provided. Also provided are methods of fabricating the transistors. The transistors, which are highly stretchable and bendable, exhibit stable performance even when operated under high tensile strains.

  16. Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J.

    2004-01-01

    This is the final technical report for NASA grant NAG5-9493. entitled "Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers". The goal of this project was to develop and demonstrate a new generation of superconducting tunnel junction (SIS) receivers with extremely wide instantaneous (intermediate-frequency, or IF) bandwidths. of order 12 GHz. along with the wideband low-noise microwave HEMT (high electron mobility transistor) amplifiers which follow the SIS mixer. These wideband SIS/HEMT receivers would allow rapid submillimeter wavelength spectral line surveys to be carried out, for instance with the NASA airborne observatory SOFIA. and could potentially be useful for future submillimeter space missions such as SAFIR. In addition, there are potential NASA earth science applications. such as the monitoring of the distribution of chemical species in the stratosphere and troposphere using the limb-sounding technique. The overall goals of this project have been achieved: a broadband 200-300 SIS receiver was designed and constructed, and was demonstrated in the field through a test run at the Caltech Submillimeter Observatory on Mauna Kea. HI. The technical details are described in the appendices. which are primarily conference publications. but Appendix A also includes an unpublished summary of the latest results. The work on the SIS mixer design are described in the conference publications (appendices B and C). The "Supermix" software package that was developed at Caltech and used for the SIS design is also described in two conference papers, but has been substantially revised, debugged. and extended as part of the work completed for this grant. The Supermix package is made available to the community at no charge. The electromagnetic design of a radial waveguide probe similar to the one used in this work is described in a journal publication. Details of the novel fabrication procedure used for producing the SIS devices at JPL are also given in an

  17. A Logarithmic Response Complementary Metal Oxide Semiconductor Image Sensor with Parasitic P-N-P Bipolar Junction Transistor

    NASA Astrophysics Data System (ADS)

    Lai, Cheng‑Hsiao; Lai, Liang‑Wei; Chiang, Wen‑Jen; King, Ya‑Chin

    2006-04-01

    Logarithmic-response complementary metal oxide semiconductor (CMOS) active pixel sensors provide a desirable attribute of wide dynamic range even with low supply voltages. In this paper, a log-mode pixel with employing parasitic P-N-P bipolar junction transistor (BJT) to amplify photo-current is investigated and optimized. A new log-mode cell with a calibration transistor is proposed to increase the output voltage swing as well as to reduce the fixed pattern noise. The measurement results demonstrate that, the output voltage swing of this new cell is enhanced by 4× and fixed pattern noise (FPN) of a pixel array can be reduced by 10× comparing to that of a conventional log-mode CMOS active pixel sensor.

  18. All-optical transistors and logic gates using a parity-time-symmetric Y-junction: Design and simulation

    SciTech Connect

    Ding, Shulin; Wang, Guo Ping

    2015-09-28

    Classical nonlinear or quantum all-optical transistors are dependent on the value of input signal intensity or need extra co-propagating beams. In this paper, we present a kind of all-optical transistors constructed with parity-time (PT)-symmetric Y-junctions, which perform independently on the value of signal intensity in an unsaturated gain case and can also work after introducing saturated gain. Further, we show that control signal can switch the device from amplification of peaks in time to transformation of peaks to amplified troughs. By using these PT-symmetric Y-junctions with currently available materials and technologies, we can implement interesting logic functions such as NOT and XOR (exclusive OR) gates, implying potential applications of such structures in designing optical logic gates, optical switches, and signal transformations or amplifications.

  19. Organic electrochemical transistors for cell-based impedance sensing

    NASA Astrophysics Data System (ADS)

    Rivnay, Jonathan; Ramuz, Marc; Leleux, Pierre; Hama, Adel; Huerta, Miriam; Owens, Roisin M.

    2015-01-01

    Electrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell motion, morphology, and cell layer/tissue integrity for high throughput toxicology screening. Existing methods to measure electrical impedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors (OECTs) are conducting polymer-based devices, which have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. In this work, we combine OECT-based drain current measurements with simultaneous measurement of more traditional impedance sensing using the gate current to produce complex impedance traces, which show low error at both low and high frequencies. We apply this technique in vitro to a model epithelial tissue layer and show that the data can be fit to an equivalent circuit model yielding trans-epithelial resistance and cell layer capacitance values in agreement with literature. Importantly, the combined measurement allows for low biases across the cell layer, while still maintaining good broadband signal.

  20. MoS2 transistors operating at gigahertz frequencies.

    PubMed

    Krasnozhon, Daria; Lembke, Dominik; Nyffeler, Clemens; Leblebici, Yusuf; Kis, Andras

    2014-10-01

    The presence of a direct band gap and an ultrathin form factor has caused a considerable interest in two-dimensional (2D) semiconductors from the transition metal dichalcogenides (TMD) family with molybdenum disulfide (MoS2) being the most studied representative of this family of materials. While diverse electronic elements, logic circuits, and optoelectronic devices have been demonstrated using ultrathin MoS2, very little is known about their performance at high frequencies where commercial devices are expected to function. Here, we report on top-gated MoS2 transistors operating in the gigahertz range of frequencies. Our devices show cutoff frequencies reaching 6 GHz. The presence of a band gap also gives rise to current saturation, allowing power and voltage gain, all in the gigahertz range. This shows that MoS2 could be an interesting material for realizing high-speed amplifiers and logic circuits with device scaling expected to result in further improvement of performance. Our work represents the first step in the realization of high-frequency analog and digital circuits based on 2D semiconductors. PMID:25243885

  1. Organic electrochemical transistors for cell-based impedance sensing

    SciTech Connect

    Rivnay, Jonathan E-mail: owens@emse.fr; Ramuz, Marc; Hama, Adel; Huerta, Miriam; Owens, Roisin M. E-mail: owens@emse.fr; Leleux, Pierre

    2015-01-26

    Electrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell motion, morphology, and cell layer/tissue integrity for high throughput toxicology screening. Existing methods to measure electrical impedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors (OECTs) are conducting polymer-based devices, which have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. In this work, we combine OECT-based drain current measurements with simultaneous measurement of more traditional impedance sensing using the gate current to produce complex impedance traces, which show low error at both low and high frequencies. We apply this technique in vitro to a model epithelial tissue layer and show that the data can be fit to an equivalent circuit model yielding trans-epithelial resistance and cell layer capacitance values in agreement with literature. Importantly, the combined measurement allows for low biases across the cell layer, while still maintaining good broadband signal.

  2. Scaling issues for analogue circuits using Double Gate SOI transistors

    NASA Astrophysics Data System (ADS)

    Lim, Tao Chuan; Armstrong, G. Alastair

    2007-02-01

    This work presents a systematic analysis on the impact of source-drain engineering using gate "non-overlapped" on the RF performance of nano-scaled fully depleted Double Gate SOI transistors, when used in the design of a typical two stage Operational Transconductance Amplifier (OTA). It is evident that for a gate length less than 40 nm, the incorporation of optimal source-drain engineering requiring a spacer length, which may exceed the length of the gate, is particularly beneficial in analogue applications. Lengthening the spacer reduces gate capacitance in the weak/moderate inversion region more than transconductance, improving cut-off frequency fT. This improvement is particularly significant in a circuit application where an optimal spacer of 1.5 times the gate length is proposed. This gate under-lapped concept with extended spacer can also significantly enhance DC gain of the OTA, by increasing the Early Voltage, while maximising the transconductance to current ratio in the weak to moderate inversion, close to threshold voltage. With optimally designed devices, the sensitivity of OTA circuit performance to doping profile is shown to be relatively low.

  3. Thin Film Transistors On Plastic Substrates

    DOEpatents

    Carey, Paul G.; Smith, Patrick M.; Sigmon, Thomas W.; Aceves, Randy C.

    2004-01-20

    A process for formation of thin film transistors (TFTs) on plastic substrates replaces standard thin film transistor fabrication techniques, and uses sufficiently lower processing temperatures so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The silicon based thin film transistor produced by the process includes a low temperature substrate incapable of withstanding sustained processing temperatures greater than about 250.degree. C., an insulating layer on the substrate, a layer of silicon on the insulating layer having sections of doped silicon, undoped silicon, and poly-silicon, a gate dielectric layer on the layer of silicon, a layer of gate metal on the dielectric layer, a layer of oxide on sections of the layer of silicon and the layer of gate metal, and metal contacts on sections of the layer of silicon and layer of gate metal defining source, gate, and drain contacts, and interconnects.

  4. A Heteroepitaxial Perovskite Metal-Base Transistor

    SciTech Connect

    Yajima, T.; Hikita, Y.; Hwang, H.Y.; /Tokyo U. /JST, PRESTO /SLAC

    2011-08-11

    'More than Moore' captures a concept for overcoming limitations in silicon electronics by incorporating new functionalities in the constituent materials. Perovskite oxides are candidates because of their vast array of physical properties in a common structure. They also enable new electronic devices based on strongly-correlated electrons. The field effect transistor and its derivatives have been the principal oxide devices investigated thus far, but another option is available in a different geometry: if the current is perpendicular to the interface, the strong internal electric fields generated at back-to-back heterojunctions can be used for oxide electronics, analogous to bipolar transistors. Here we demonstrate a perovskite heteroepitaxial metal-base transistor operating at room temperature, enabled by interface dipole engineering. Analysis of many devices quantifies the evolution from hot-electron to permeable-base behaviour. This device provides a platform for incorporating the exotic ground states of perovskite oxides, as well as novel electronic phases at their interfaces.

  5. High Performance Airbrushed Organic Thin Film Transistors

    SciTech Connect

    Chan, C.; Richter, L; Dinardo, B; Jaye, C; Conrad, B; Ro, H; Germack, D; Fischer, D; DeLongchamp, D; Gunlach, D

    2010-01-01

    Spray-deposited poly-3-hexylthiophene (P3HT) transistors were characterized using electrical and structural methods. Thin-film transistors with octyltrichlorosilane treated gate dielectrics and spray-deposited P3HT active layers exhibited a saturation regime mobility as high as 0.1 cm{sup 2} V{sup -1} s{sup -1}, which is comparable to the best mobilities observed in high molecular mass P3HT transistors prepared using other methods. Optical and atomic force microscopy showed the presence of individual droplets with an average diameter of 20 {micro}m and appreciable large-scale film inhomogeneities. Despite these inhomogeneities, near-edge x-ray absorption fine structure spectroscopy of the device-relevant channel interface indicated excellent orientation of the P3HT.

  6. Transistors using crystalline silicon devices on glass

    DOEpatents

    McCarthy, A.M.

    1995-05-09

    A method is disclosed for fabricating transistors using single-crystal silicon devices on glass. This method overcomes the potential damage that may be caused to the device during high voltage bonding and employs a metal layer which may be incorporated as part of the transistor. This is accomplished such that when the bonding of the silicon wafer or substrate to the glass substrate is performed, the voltage and current pass through areas where transistors will not be fabricated. After removal of the silicon substrate, further metal may be deposited to form electrical contact or add functionality to the devices. By this method both single and gate-all-around devices may be formed. 13 figs.

  7. Environmentally friendly transistors and circuits on paper.

    PubMed

    Pettersson, Fredrik; Remonen, Tommi; Adekanye, David; Zhang, Yanxi; Wilén, Carl-Eric; Österbacka, Ronald

    2015-04-27

    We created environmentally friendly low-voltage, ion-modulated transistors (IMTs) that can be fabricated successfully on a paper substrate. A range of ionic liquids (ILs) based on choline chloride (ChoCl) were used as the electrolytic layer in the IMTs. Different organic compounds were mixed with ChoCl to create solution-processable deep eutectic mixtures that are liquid or semiliquid at room temperature. In the final, solid version of the IMT, the ILs are also solidified by using a commercial binder to create printable transistor structures The semiconductor layer in the IMT is also substituted with a blend of the original semiconductor and a biodegradable polymer insulator. This reduces the amount of expensive and potentially harmful semiconductor used, and it also provides increased transistor performance, especially increasing the device switching speed. These environmentally friendly IMTs are then used to create ring oscillators, logic gates, and memories on paper.

  8. Switching Characteristics of Ferroelectric Transistor Inverters

    NASA Technical Reports Server (NTRS)

    Laws, Crystal; Mitchell, Coey; MacLeod, Todd C.; Ho, Fat D.

    2010-01-01

    This paper presents the switching characteristics of an inverter circuit using a ferroelectric field effect transistor, FeFET. The propagation delay time characteristics, phl and plh are presented along with the output voltage rise and fall times, rise and fall. The propagation delay is the time-delay between the V50% transitions of the input and output voltages. The rise and fall times are the times required for the output voltages to transition between the voltage levels V10% and V90%. Comparisons are made between the MOSFET inverter and the ferroelectric transistor inverter.

  9. Static Characteristics of the Ferroelectric Transistor Inverter

    NASA Technical Reports Server (NTRS)

    Mitchell, Cody; Laws, crystal; MacLeond, Todd C.; Ho, Fat D.

    2010-01-01

    The inverter is one of the most fundamental building blocks of digital logic, and it can be used as the foundation for understanding more complex logic gates and circuits. This paper presents the characteristics of an inverter circuit using a ferroelectric field-effect transistor. The voltage transfer characteristics are analyzed with respect to varying parameters such as supply voltage, input voltage, and load resistance. The effects of the ferroelectric layer between the gate and semiconductor are examined, and comparisons are made between the inverters using ferroelectric transistors and those using traditional MOSFETs.

  10. Behavior of subthreshold conduction in junctionless transistors

    NASA Astrophysics Data System (ADS)

    Park, So Jeong; Jeon, Dae-Young; Montès, Laurent; Mouis, Mireille; Barraud, Sylvain; Kim, Gyu-Tae; Ghibaudo, Gérard

    2016-10-01

    In this work, the effect of high channel doping concentration and unique structure of junctionless transistors (JLTs) is investigated in the subthreshold conduction regime. Both experimental results and simulation work show that JLTs have reduced portion of the diffusion conduction and lower effective barrier height between source/drain and the silicon channel in subthreshold regime, compared to conventional inversion-mode (IM) transistors. Finally, it leads to a relatively large DIBL value in JLTs, owing to degraded gate controllability on channel region and strong drain bias effect. However, JLTs showed a better immunity against short channel effect in terms of degradation of the effective barrier height value.

  11. p-type metal-base transistor

    NASA Astrophysics Data System (ADS)

    Delatorre, R. G.; Munford, M. L.; Zandonay, R.; Zoldan, V. C.; Pasa, A. A.; Schwarzacher, W.; Meruvia, M. S.; Hümmelgen, I. A.

    2006-06-01

    In this work we present data from a novel p-type metal-base transistor with common-base gain α ˜1, fabricated at ambient temperature and pressure by electrodepositing sequentially on a p-type Si collector, a Co base and a Cu2O emitter. The high gain and the dependence of potential between emitter and base (VEB) on the potential between collector and base (VCB) when the emitter current (IE) is held constant both suggest that the device functions as a natural permeable base transistor for very thin metal bases.

  12. Going ballistic: Graphene hot electron transistors

    NASA Astrophysics Data System (ADS)

    Vaziri, S.; Smith, A. D.; Östling, M.; Lupina, G.; Dabrowski, J.; Lippert, G.; Mehr, W.; Driussi, F.; Venica, S.; Di Lecce, V.; Gnudi, A.; König, M.; Ruhl, G.; Belete, M.; Lemme, M. C.

    2015-12-01

    This paper reviews the experimental and theoretical state of the art in ballistic hot electron transistors that utilize two-dimensional base contacts made from graphene, i.e. graphene base transistors (GBTs). Early performance predictions that indicated potential for THz operation still hold true today, even with improved models that take non-idealities into account. Experimental results clearly demonstrate the basic functionality, with on/off current switching over several orders of magnitude, but further developments are required to exploit the full potential of the GBT device family. In particular, interfaces between graphene and semiconductors or dielectrics are far from perfect and thus limit experimental device integrity, reliability and performance.

  13. VHDL simulation with access to transistor models

    NASA Technical Reports Server (NTRS)

    Gibson, J.

    1991-01-01

    Hardware description languages such as VHDL have evolved to aid in the design of systems with large numbers of elements and a wide range of electronic and logical abstractions. For high performance circuits, behavioral models may not be able to efficiently include enough detail to give designers confidence in a simulation's accuracy. One option is to provide a link between the VHDL environment and a transistor level simulation environment. The coupling of the Vantage Analysis Systems VHDL simulator and the NOVA simulator provides the combination of VHDL modeling and transistor modeling.

  14. Bipolar effects in unipolar junctionless transistors

    NASA Astrophysics Data System (ADS)

    Parihar, Mukta Singh; Ghosh, Dipankar; Armstrong, G. Alastair; Yu, Ran; Razavi, Pedram; Kranti, Abhinav

    2012-08-01

    In this work, we analyze hysteresis and bipolar effects in unipolar junctionless transistors. A change in subthreshold drain current by 5 orders of magnitude is demonstrated at a drain voltage of 2.25 V in silicon junctionless transistor. Contrary to the conventional theory, increasing gate oxide thickness results in (i) a reduction of subthreshold slope (S-slope) and (ii) an increase in drain current, due to bipolar effects. The high sensitivity to film thickness in junctionless devices will be most crucial factor in achieving steep transition from ON to OFF state.

  15. Noise figure of hybrid optical parametric amplifiers.

    PubMed

    Marhic, Michel E

    2012-12-17

    Following a fiber optical parametric amplifier, used as a wavelength converter or in the phase-sensitive mode, by a phase-insensitive amplifier (PIA) can significantly reduce four-wave mixing between signals in broadband systems. We derive the quantum mechanical noise figures (NF) for these two hybrid configurations, and show that adding the PIA only leads to a moderate increase in NF.

  16. Bridge/amplifier configuration for switched arrays

    NASA Technical Reports Server (NTRS)

    Bohning, O. D.

    1977-01-01

    Bridge network connected to differential amplifier and used with bubble-domain memories draws no power during standby and can be arrayed with other bridge amplifiers of like design. Two-node arrangement greatly simplifies conventional configurations where more than two nodes are involved.

  17. Method for reducing snap in magnetic amplifiers

    NASA Technical Reports Server (NTRS)

    Fischer, R. L. E.; Word, J. L.

    1968-01-01

    Method of reducing snap in magnetic amplifiers uses a degenerative feedback circuit consisting of a resistor and a separate winding on a magnetic core. The feedback circuit extends amplifier range by allowing it to be used at lower values of output current.

  18. Design and performance of the beamlet amplifiers

    SciTech Connect

    Erlandson, A.C.; Rotter, M.D.; Frank, M.D.; McCracken, R.W.

    1996-06-01

    In future laser systems, such as the National Ignition Facility (NIF), multi-segment amplifiers (MSAs) will be used to amplify the laser beam to the required levels. As a prototype of such a laser architecture, the authors have designed, built, and tested flash-lamp-pumped, Nd:Glass, Brewster-angle slab MSAs for the Beamlet project. In this article, they review the fundamentals of Nd:Glass amplifiers, describe the MSA geometry, discuss parameters that are important in amplifier design, and present our results on the characterization of the Beamlet MSAs. In particular, gain and beam steering measurements show that the Beamlet amplifiers meet all optical performance specifications and perform close to model predictions.

  19. Amplified OTDR Systems for Multipoint Corrosion Monitoring

    PubMed Central

    Nascimento, Jehan F.; Silva, Marcionilo J.; Coêlho, Isnaldo J. S.; Cipriano, Eliel; Martins-Filho, Joaquim F.

    2012-01-01

    We present two configurations of an amplified fiber-optic-based corrosion sensor using the optical time domain reflectometry (OTDR) technique as the interrogation method. The sensor system is multipoint, self-referenced, has no moving parts and can measure the corrosion rate several kilometers away from the OTDR equipment. The first OTDR monitoring system employs a remotely pumped in-line EDFA and it is used to evaluate the increase in system reach compared to a non-amplified configuration. The other amplified monitoring system uses an EDFA in booster configuration and we perform corrosion measurements and evaluations of system sensitivity to amplifier gain variations. Our experimental results obtained under controlled laboratory conditions show the advantages of the amplified system in terms of longer system reach with better spatial resolution, and also that the corrosion measurements obtained from our system are not sensitive to 3 dB gain variations. PMID:22737017

  20. Dual-range linearized transimpedance amplifier system

    DOEpatents

    Wessendorf, Kurt O.

    2010-11-02

    A transimpedance amplifier system is disclosed which simultaneously generates a low-gain output signal and a high-gain output signal from an input current signal using a single transimpedance amplifier having two different feedback loops with different amplification factors to generate two different output voltage signals. One of the feedback loops includes a resistor, and the other feedback loop includes another resistor in series with one or more diodes. The transimpedance amplifier system includes a signal linearizer to linearize one or both of the low- and high-gain output signals by scaling and adding the two output voltage signals from the transimpedance amplifier. The signal linearizer can be formed either as an analog device using one or two summing amplifiers, or alternately can be formed as a digital device using two analog-to-digital converters and a digital signal processor (e.g. a microprocessor or a computer).

  1. Post pulse shutter for laser amplifier

    DOEpatents

    Bradley, L.P.; Carder, B.M.; Gagnon, W.L.

    1981-03-17

    Disclosed are an apparatus and method for quickly closing off the return path for an amplified laser pulse at the output of an amplifier so as to prevent damage to amplifiers and other optical components appearing earlier in the chain by the return of an amplified pulse. The apparatus consists of a fast retropulse or post pulse shutter to suppress target reflection and/or beam return. This is accomplished by either quickly placing a solid across the light transmitting aperture of a component in the chain, such as a spatial filter pinhole, or generating and directing a plasma with sufficiently high density across the aperture, so as to, in effect, close the aperture to the returning amplified energy pulse. 13 figs.

  2. Post pulse shutter for laser amplifier

    DOEpatents

    Bradley, Laird P. [Livermore, CA; Carder, Bruce M. [Antioch, CA; Gagnon, William L. [Berkeley, CA

    1981-03-17

    Apparatus and method for quickly closing off the return path for an amplified laser pulse at the output of an amplifier so as to prevent damage to amplifiers and other optical components appearing earlier in the chain by the return of an amplified pulse. The apparatus consists of a fast retropulse or post pulse shutter to suppress target reflection and/or beam return. This is accomplished by either quickly placing a solid across the light transmitting aperture of a component in the chain, such as a spatial filter pinhole, or generating and directing a plasma with sufficiently high density across the aperture, so as to, in effect, close the aperture to the returning amplified energy pulse.

  3. Fiber networks amplify active stress

    NASA Astrophysics Data System (ADS)

    Lenz, Martin; Ronceray, Pierre; Broedersz, Chase

    Large-scale force generation is essential for biological functions such as cell motility, embryonic development, and muscle contraction. In these processes, forces generated at the molecular level by motor proteins are transmitted by disordered fiber networks, resulting in large-scale active stresses. While fiber networks are well characterized macroscopically, this stress generation by microscopic active units is not well understood. I will present a comprehensive theoretical study of force transmission in these networks. I will show that the linear, small-force response of the networks is remarkably simple, as the macroscopic active stress depends only on the geometry of the force-exerting unit. In contrast, as non-linear buckling occurs around these units, local active forces are rectified towards isotropic contraction and strongly amplified. This stress amplification is reinforced by the networks' disordered nature, but saturates for high densities of active units. I will show that our predictions are quantitatively consistent with experiments on reconstituted tissues and actomyosin networks, and that they shed light on the role of the network microstructure in shaping active stresses in cells and tissue.

  4. Multi-pass light amplifier

    NASA Technical Reports Server (NTRS)

    Plaessmann, Henry (Inventor); Grossman, William M. (Inventor)

    1997-01-01

    A multiple-pass laser amplifier that uses optical focusing between subsequent passes through a single gain medium so that a reproducibly stable beam size is achieved within the gain region. A confocal resonator or White Cell resonator is provided, including two or three curvilinearly shaped mirrors facing each other along a resonator axis and an optical gain medium positioned on the resonator axis between the mirrors (confocal resonator) or adjacent to one of the mirrors (White Cell). In a first embodiment, two mirrors, which may include adjacent lenses, are configured so that a light beam passing through the gain medium and incident on the first mirror is reflected by that mirror toward the second mirror in a direction approximately parallel to the resonator axis. A light beam translator, such as an optical flat of transparent material, is positioned to translate this light beam by a controllable amount toward or away from the resonator axis for each pass of the light beam through the translator. The optical gain medium may be solid-state, liquid or gaseous medium and may be pumped longitudinally or transversely. In a second embodiment, first and second mirrors face a third mirror in a White Cell configuration, and the optical gain medium is positioned at or adjacent to one of the mirrors. Defocusing means and optical gain medium cooling means are optionally provided with either embodiment, to controllably defocus the light beam, to cool the optical gain medium and to suppress thermal lensing in the gain medium.

  5. Ultrafast laser and amplifier sources

    NASA Astrophysics Data System (ADS)

    Rundquist, A.; Durfee, C.; Chang, Z.; Taft, G.; Zeek, E.; Backus, S.; Murnane, M. M.; Kapteyn, H. C.; Christov, I.; Stoev, V.

    1997-08-01

    There has been remarkable progress in the development of high peak-power ultrafast lasers in recent years. Lasers capable of generating terawatt peak powers with unprecedented short pulse durations can now be built on a single optical table in a small laboratory. The rapid technological progress has made possible a host of new scientific advances in high-field science, such as the generation of coherent femtosecond X-ray pulses, and the generation of MeV-energy electron beams and high-energy ions. In this paper, we review progress in the development and design of ultrafast high-power lasers based on Ti:sapphire, including the ultrafast laser oscillators that are a very important enabling technology for high-power ultrafast systems, and ultrafast amplified laser systems that generate 20 fs duration pulses with several watts average power at kilohertz repetition-rates. Ultrafast waveform measurements of these pulses demonstrate that such short pulses can be generated with high fidelity. Finally, we discuss applications of ultrafast high-power pulses, including the generation of femtosecond to attosecond X-ray pulses.

  6. Ultrafast disk lasers and amplifiers

    NASA Astrophysics Data System (ADS)

    Sutter, Dirk H.; Kleinbauer, Jochen; Bauer, Dominik; Wolf, Martin; Tan, Chuong; Gebs, Raphael; Budnicki, Aleksander; Wagenblast, Philipp; Weiler, Sascha

    2012-03-01

    Disk lasers with multi-kW continuous wave (CW) output power are widely used in manufacturing, primarily for cutting and welding applications, notably in the automotive industry. The ytterbium disk technology combines high power (average and/or peak power), excellent beam quality, high efficiency, and high reliability with low investment and operating costs. Fundamental mode picosecond disk lasers are well established in micro machining at high throughput and perfect precision. Following the world's first market introduction of industrial grade 50 W picosecond lasers (TruMicro 5050) at the Photonics West 2008, the second generation of the TruMicro series 5000 now provides twice the average power (100 W at 1030 nm, or 60 W frequency doubled, green output) at a significantly reduced footprint. Mode-locked disk oscillators achieve by far the highest average power of any unamplified lasers, significantly exceeding the 100 W level in laboratory set-ups. With robust long resonators their multi-microjoule pulse energies begin to compete with typical ultrafast amplifiers. In addition, significant interest in disk technology has recently come from the extreme light laser community, aiming for ultra-high peak powers of petawatts and beyond.

  7. A comparison of the kink effect in polysilicon thin film transistors and silicon on insulator transistors

    NASA Astrophysics Data System (ADS)

    Armstrong, G. A.; Brotherton, S. D.; Ayres, J. R.

    1996-09-01

    Polysilicon thin film transistors (TFTs) differ from conventional silicon on insulator (SOI) transistors in that the TFT exhibits a fundamental gate length dependence of the voltage at which a kink occurs in the output characteristics. This difference is shown to be caused by the peak lateral electric field being strongly dependent on the doping density in an SOI transistor, but relatively insensitive to trap distribution in a TFT. Source barrier lowering which occurs in SOI transistors is absent in a TFT, where the increase in current is the result of a field redistribution along the channel. For very short gate lengths, the TFT exhibits a small pseudo-bipolar gain. Estimates of this bipolar gain can be made by simulation of TFT characteristics with and without impact ionisation. The magnitude of the gain is shown to be approximately inversely proportional to gate length.

  8. Materials physics and device development for improved efficiency of GaN HEMT high power amplifiers.

    SciTech Connect

    Kurtz, Steven Ross; Follstaedt, David Martin; Wright, Alan Francis; Baca, Albert G.; Briggs, Ronald D.; Provencio, Paula Polyak; Missert, Nancy A.; Allerman, Andrew Alan; Marsh, Phil F.; Koleske, Daniel David; Lee, Stephen Roger; Shul, Randy John; Seager, Carleton Hoover; Tigges, Christopher P.

    2005-12-01

    GaN-based microwave power amplifiers have been identified as critical components in Sandia's next generation micro-Synthetic-Aperture-Radar (SAR) operating at X-band and Ku-band (10-18 GHz). To miniaturize SAR, GaN-based amplifiers are necessary to replace bulky traveling wave tubes. Specifically, for micro-SAR development, highly reliable GaN high electron mobility transistors (HEMTs), which have delivered a factor of 10 times improvement in power performance compared to GaAs, need to be developed. Despite the great promise of GaN HEMTs, problems associated with nitride materials growth currently limit gain, linearity, power-added-efficiency, reproducibility, and reliability. These material quality issues are primarily due to heteroepitaxial growth of GaN on lattice mismatched substrates. Because SiC provides the best lattice match and thermal conductivity, SiC is currently the substrate of choice for GaN-based microwave amplifiers. Obviously for GaN-based HEMTs to fully realize their tremendous promise, several challenges related to GaN heteroepitaxy on SiC must be solved. For this LDRD, we conducted a concerted effort to resolve materials issues through in-depth research on GaN/AlGaN growth on SiC. Repeatable growth processes were developed which enabled basic studies of these device layers as well as full fabrication of microwave amplifiers. Detailed studies of the GaN and AlGaN growth of SiC were conducted and techniques to measure the structural and electrical properties of the layers were developed. Problems that limit device performance were investigated, including electron traps, dislocations, the quality of semi-insulating GaN, the GaN/AlGaN interface roughness, and surface pinning of the AlGaN gate. Surface charge was reduced by developing silicon nitride passivation. Constant feedback between material properties, physical understanding, and device performance enabled rapid progress which eventually led to the successful fabrication of state of the art

  9. Transistor-based particle detection systems and methods

    DOEpatents

    Jain, Ankit; Nair, Pradeep R.; Alam, Muhammad Ashraful

    2015-06-09

    Transistor-based particle detection systems and methods may be configured to detect charged and non-charged particles. Such systems may include a supporting structure contacting a gate of a transistor and separating the gate from a dielectric of the transistor, and the transistor may have a near pull-in bias and a sub-threshold region bias to facilitate particle detection. The transistor may be configured to change current flow through the transistor in response to a change in stiffness of the gate caused by securing of a particle to the gate, and the transistor-based particle detection system may configured to detect the non-charged particle at least from the change in current flow.

  10. Reconfigurable Complementary Logic Circuits with Ambipolar Organic Transistors

    PubMed Central

    Yoo, Hocheon; Ghittorelli, Matteo; Smits, Edsger C. P.; Gelinck, Gerwin H.; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

    2016-01-01

    Ambipolar organic electronics offer great potential for simple and low-cost fabrication of complementary logic circuits on large-area and mechanically flexible substrates. Ambipolar transistors are ideal candidates for the simple and low-cost development of complementary logic circuits since they can operate as n-type and p-type transistors. Nevertheless, the experimental demonstration of ambipolar organic complementary circuits is limited to inverters. The control of the transistor polarity is crucial for proper circuit operation. Novel gating techniques enable to control the transistor polarity but result in dramatically reduced performances. Here we show high-performance non-planar ambipolar organic transistors with electrical control of the polarity and orders of magnitude higher performances with respect to state-of-art split-gate ambipolar transistors. Electrically reconfigurable complementary logic gates based on ambipolar organic transistors are experimentally demonstrated, thus opening up new opportunities for ambipolar organic complementary electronics. PMID:27762321

  11. Solid state power amplifier as 805 MHz master source for the LANSCE coupled-cavity linac

    SciTech Connect

    Lyles, J.; Davis, J.

    1998-12-31

    From 100 to 800 MeV, the Los Alamos Neutron Science Center (LANSCE) proton linac receives RF power from forty-four 1.25 MW klystrons at 805 Megahertz (MHz). A single master RF source provides a continuous high level phase reference signal which drives the klystrons along the 731 meter-long linac through a coaxial transmission line. A single point failure of this system can deenergize the entire coupled-cavity linac (CCL) RF plant. The authors replaced a physically large air-cooled tetrode amplifier with a compact water-cooled unit based on modular amplifier pallets developed at LANSCE. Each 600 Watt pallet utilizes eight push-pull bipolar power transistor pairs operated in class AB. Four of these can easily provide the 2000 watt reference carrier from the stable master RF source. A radial splitter and combiner parallels the modules. This amplifier has proven to be completely reliable after two years of operation without failure. A second unit was constructed and installed for redundancy, and the old tetrode system was removed in 1998. The compact packaging for cooling, DC power, impedance matching, RF interconnection, and power combining met the electrical and mechanical requirements. CRT display of individual collector currents and RF levels is made possible with built-in samplers and a VXI data acquisition unit.

  12. A 2.3-GHz low-noise cryo-FET amplifier

    NASA Technical Reports Server (NTRS)

    Loreman, J.

    1988-01-01

    A cryogenic cooled, low-noise Field Effect Transistor (FET) amplifier assembly for use at 2.2 to 2.3 GHz was developed for the DSN to meet the requirements of a Very Long Baseline Interferometry (VLBI) upgrade. An amplifier assembly was developed at JPL that uses a commercial closed-cycle helium refrigerator (CCR) to cool a FET amplifier to an operating temperature of 15 K. A cooled probe waveguide-to-coaxial transition similar to that used in the research and development Ultra-Low-Noise S-band Traveling Wave Maser (TWM) is used to minimize input line losses. Typical performance includes an input flange equivalent noise contribution of 14.5 K, a gain slope of less than 0.05 dB/MHz across a bandwidth of 2.2 to 2.3 GHz, an input VSWR of 1.5:1 at 2.25 GHz, and an insertion gain of 45 + or - 1 dB across the bandwidth of 2.2 to 2.3 GHz. Three 2.3 GHz FET/CCR assemblies were delivered to the DSN in the spring of 1987.

  13. Radiation Tolerance of 65nm CMOS Transistors

    DOE PAGES

    Krohn, M.; Bentele, B.; Christian, D. C.; Cumalat, J. P.; Deptuch, G.; Fahim, F.; Hoff, J.; Shenai, A.; Wagner, S. R.

    2015-12-11

    We report on the effects of ionizing radiation on 65 nm CMOS transistors held at approximately -20°C during irradiation. The pattern of damage observed after a total dose of 1 Grad is similar to damage reported in room temperature exposures, but we observe less damage than was observed at room temperature.

  14. Gallium nitride junction field-effect transistor

    DOEpatents

    Zolper, John C.; Shul, Randy J.

    1999-01-01

    An all-ion implanted gallium-nitride (GaN) junction field-effect transistor (JFET) and method of making the same. Also disclosed are various ion implants, both n- and p-type, together with or without phosphorous co-implantation, in selected III-V semiconductor materials.

  15. Gallium nitride junction field-effect transistor

    DOEpatents

    Zolper, J.C.; Shul, R.J.

    1999-02-02

    An ion implanted gallium-nitride (GaN) junction field-effect transistor (JFET) and method of making the same are disclosed. Also disclosed are various ion implants, both n- and p-type, together with or without phosphorus co-implantation, in selected III-V semiconductor materials. 19 figs.

  16. Black phosphorus radio-frequency transistors.

    PubMed

    Wang, Han; Wang, Xiaomu; Xia, Fengnian; Wang, Luhao; Jiang, Hao; Xia, Qiangfei; Chin, Matthew L; Dubey, Madan; Han, Shu-jen

    2014-11-12

    Few-layer and thin film forms of layered black phosphorus (BP) have recently emerged as a promising material for applications in high performance nanoelectronics and infrared optoelectronics. Layered BP thin films offer a moderate bandgap of around 0.3 eV and high carrier mobility, which lead to transistors with decent on-off ratios and high on-state current densities. Here, we demonstrate the gigahertz frequency operation of BP field-effect transistors for the first time. The BP transistors demonstrated here show respectable current saturation with an on-off ratio that exceeds 2 × 10(3). We achieved a current density in excess of 270 mA/mm and DC transconductance above 180 mS/mm for hole conduction. Using standard high frequency characterization techniques, we measured a short-circuit current-gain cutoff frequency fT of 12 GHz and a maximum oscillation frequency fmax of 20 GHz in 300 nm channel length devices. BP devices may offer advantages over graphene transistors for high frequency electronics in terms of voltage and power gain due to the good current saturation properties arising from their finite bandgap, thus can be considered as a promising candidate for the future high performance thin film electronics technology for operation in the multi-GHz frequency range and beyond.

  17. Progress on diamond amplified photo-cathode

    SciTech Connect

    Wang, E.; Ben-Zvi, I.; Burrill, A.; Kewisch, J.; Chang, X.; Rao, T.; Smedley, J.; Wu, Q.; Muller, E.; Xin, T.

    2011-03-28

    Two years ago, we obtained an emission gain of 40 from the Diamond Amplifier Cathode (DAC) in our test system. In our current systematic study of hydrogenation, the highest gain we registered in emission scanning was 178. We proved that our treatments for improving the diamond amplifiers are reproducible. Upcoming tests planned include testing DAC in a RF cavity. Already, we have designed a system for these tests using our 112 MHz superconducting cavity, wherein we will measure DAC parameters, such as the limit, if any, on emission current density, the bunch charge, and the bunch length. The diamond-amplified photocathode, that promises to support a high average current, low emittance, and a highly stable electron beam with a long lifetime, is under development for an electron source. The diamond, functioning as a secondary emitter amplifies the primary current, with a few KeV energy, that comes from the traditional cathode. Earlier, our group recorded a maximum gain of 40 in the secondary electron emission from a diamond amplifier. In this article, we detail our optimization of the hydrogenation process for a diamond amplifier that resulted in a stable emission gain of 140. We proved that these characteristics are reproducible. We now are designing a system to test the diamond amplifier cathode using an 112MHz SRF gun to measure the limits of the emission current's density, and on the bunch charge and bunch length.

  18. High power Ka band TWT amplifier

    SciTech Connect

    Golkowski, C.; Ivers, J.D.; Nation, J.A.; Wang, P.; Schachter, L.

    1999-07-01

    Two high power 35 GHz TWT amplifiers driven by a relativistic pencil, 850 kV, 200A electron beam have been assembled and tested. The first had a dielectric slow wave structure and was primarily used to develop diagnostics, and to gain experience in working with high power systems in Ka band. The source of the input power for the amplifier was a magnetron producing a 30 kW, 200ns long pulse of which 10 kW as delivered to the experiment. The 30 cm long dielectric (Teflon) amplifier produced output power levels of about 1 MW with a gain of about 23 dB. These results are consistent with expectations from PIC code simulations for this arrangement. The second amplifier, which is a single stage disk loaded slow wave structure, has been designed. It consists of one hundred uniform cells with two sets of ten tapered calls at the ends to lower the reflection coefficient. The phase advance per cell is {pi}/2. The amplifier passband extends from 28 to 40 GHz. It is designed to increase the output power to about 20 MW. The amplifier is in construction and will be tested in the near future. Details of the design of both systems will be provided and initial results from the new amplifier presented.

  19. Quasi-optical constrained lens amplifiers

    NASA Astrophysics Data System (ADS)

    Schoenberg, Jon S.

    1995-09-01

    A major goal in the field of quasi-optics is to increase the power available from solid state sources by combining the power of individual devices in free space, as demonstrated with grid oscillators and grid amplifiers. Grid amplifiers and most amplifier arrays require a plane wave feed, provided by a far field source or at the beam waist of a dielectric lens pair. These feed approaches add considerable loss and size, which is usually greater than the quasi-optical amplifier gain. In addition, grid amplifiers require external polarizers for stability, further increasing size and complexity. This thesis describes using constrained lens theory in the design of quasi optical amplifier arrays with a focal point feed, improving the power coupling between the feed and the amplifier for increased gain. Feed and aperture arrays of elements, input/output isolation and stability, amplifier circuitry, delay lines and bias distribution are all contained on a single planar substrate, making monolithic circuit integration possible. Measured results of X band transmission lenses and a low noise receive lens are presented, including absolute power gain up to 13 dB, noise figure as low as 1.7 dB, beam scanning to +/-30 deg, beam forming and beam switching of multiple sources, and multiple level quasi-optical power combining. The design and performance of millimeter wave power combining amplifier arrays is described, including a Ka Band hybrid array with 1 watt output power, and a V Band 36 element monolithic array with a 5 dB on/off ratio.

  20. A Low-Noise Semiconductor Optical Amplifier

    SciTech Connect

    Ratowsky, R.P.; Dijaili, S.; Kallman, J.S.; Feit, M.D.; Walker, J.

    1999-03-23

    Optical amplifiers are essential devices for optical networks, optical systems, and computer communications. These amplifiers compensate for the inevitable optical loss in long-distance propagation (>50 km) or splitting (>10x). Fiber amplifiers such as the erbium-doped fiber amplifier have revolutionized the fiber-optics industry and are enjoying widespread use. Semiconductor optical amplifiers (SOAs) are an alternative technology that complements the fiber amplifiers in cost and performance. One obstacle to the widespread use of SOAs is the severity of the inevitable noise output resulting from amplified spontaneous emission (ASE). Spectral filtering is often used to reduce ASE noise, but this constrains the source spectrally, and improvement is typically limited to about 10 dB. The extra components also add cost and complexity to the final assembly. The goal of this project was to analyze, design, and take significant steps toward the realization of an innovative, low-noise SOA based on the concept of ''distributed spatial filtering'' (DSF). In DSF, we alternate active SOA segments with passive free-space diffraction regions. Since spontaneous emission radiates equally in all directions, the free-space region lengthens the amplifier for a given length of gain region, narrowing the solid angle into which the spontaneous emission is amplified [1,2]. Our innovation is to use spatial filtering in a differential manner across many segments, thereby enhancing the effect when wave-optical effects are included [3]. The structure quickly and effectively strips the ASE into the higher-order modes, quenching the ASE gain relative to the signal.

  1. Diode amplifier of modulated optical beam power

    SciTech Connect

    D'yachkov, N V; Bogatov, A P; Gushchik, T I; Drakin, A E

    2014-11-30

    Analytical relations are obtained between characteristics of modulated light at the output and input of an optical diode power amplifier operating in the highly saturated gain regime. It is shown that a diode amplifier may act as an amplitude-to-phase modulation converter with a rather large bandwidth (∼10 GHz). The low sensitivity of the output power of the amplifier to the input beam power and its high energy efficiency allow it to be used as a building block of a high-power multielement laser system with coherent summation of a large number of optical beams. (lasers)

  2. Phase noise in RF and microwave amplifiers.

    PubMed

    Boudot, Rodolphe; Rubiola, Enrico

    2012-12-01

    Understanding amplifier phase noise is a critical issue in many fields of engineering and physics, such as oscillators, frequency synthesis, telecommunication, radar, and spectroscopy; in the emerging domain of microwave photonics; and in exotic fields, such as radio astronomy, particle accelerators, etc. Focusing on the two main types of base noise in amplifiers, white and flicker, the power spectral density of the random phase φ(t) is Sφ(f) = b(0) + b(-1)/f. White phase noise results from adding white noise to the RF spectrum in the carrier region. For a given RF noise level, b(0) is proportional to the reciprocal of the carrier power P(0). By contrast, flicker results from a near-dc 1/f noise-present in all electronic devices-which modulates the carrier through some parametric effect in the semiconductor. Thus, b(-1) is a parameter of the amplifier, constant in a wide range of P(0). The consequences are the following: Connecting m equal amplifiers in parallel, b(-1) is 1/m times that of one device. Cascading m equal amplifiers, b(-1) is m times that of one amplifier. Recirculating the signal in an amplifier so that the gain increases by a power of m (a factor of m in decibels) as a result of positive feedback (regeneration), we find that b(-1) is m(2) times that of the amplifier alone. The feedforward amplifier exhibits extremely low b(-1) because the carrier is ideally nulled at the input of its internal error amplifier. Starting with an extensive review of the literature, this article introduces a system-oriented model which describes the phase flickering. Several amplifier architectures (cascaded, parallel, etc.) are analyzed systematically, deriving the phase noise from the general model. There follow numerous measurements of amplifiers using different technologies, including some old samples, and in a wide frequency range (HF to microwaves), which validate the theory. In turn, theory and results provide design guidelines and give suggestions for CAD and

  3. High Efficiency Microwave Power Amplifier (HEMPA) Design

    NASA Technical Reports Server (NTRS)

    Sims, W. Herbert

    2004-01-01

    This paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built that demonstrated conversion efficiencies four to five times higher than current state of the art.

  4. Very high gain Nd:YLF amplifiers

    SciTech Connect

    Knights, M.G.; Thomas, M.D.; Chicklis, E.P.; Rines, G.A.; Seka, W.

    1988-05-01

    The authors report on high gain Nd:YLF rod amplifiers in which single-pass, small signal gains of over 1700 have been obtained along with stored energy densitiesgreater than or equal to0.4J/cm/sup 3/. The ability of Nd:YLF amplifiers to support such gains is a result of high parasitic oscillation thresholds, due primarily to the low refractive index of the material. These results suggest that Nd:YLF is an excellent candidate for amplifiers where high specific stored energies and/or very high gains are required.

  5. Achieving and maintaining cleanliness in NIF amplifiers

    SciTech Connect

    Burnham, A. K.; Horvath, J. A.; Letts, S. A.; Menapace, J. A.; Stowers, I. F.

    1998-07-28

    Cleanliness measurements made on AMPLAB prototype National Ignition Facility (NIF) laser amplifiers during assembly, cassette transfer, and amplifier operation are summarized. These measurements include particle counts from surface cleanliness assessments using filter swipe techniques and from airborne particle monitoring. Results are compared with similar measurements made on the Beamlet and Nova lasers and in flashlamp test fixtures. Observations of Class 100,000 aerosols after flashlamp firings are discussed. Comparisons are made between typical damage densities on laser amplifier optics from Novette, NOVA, Beamlet, and AMPLAB.

  6. Phase-stable, microwave FEL amplifier

    SciTech Connect

    Carlsten, B.E.; Fazio, M.V.; Haynes, W.B.; May, L.; Potter, M.

    1995-07-01

    Free-electron laser (FEL) amplifiers have demonstrated high efficiency and high output power for microwave wavelengths. However, using present technology, microwave FEL amplifiers are not phase stable enough to be suitable for driving linear accelerators, where several much amplifiers need to be phase locked. The growing wave`s phase sensitivity to the beam voltage in the small-signal gain regime is responsible for the largest contribution to this phase instability. We discuss a scheme that reduces the phase sensitivity to the beam voltage by operating off synchronism and matching the phase variation resulting from the desynchronism to the phase variation from the reduced plasma wavenumber as the beam voltage changes.

  7. High fidelity readout of a transmon qubit using a superconducting low-inductance undulatory galvanometer microwave amplifier

    NASA Astrophysics Data System (ADS)

    Liu, Yanbing; Srinivasan, Srikanth J.; Hover, D.; Zhu, Shaojiang; McDermott, R.; Houck, A. A.

    2014-11-01

    We report high-fidelity, quantum non-demolition, single-shot readout of a superconducting transmon qubit using a dc-biased superconducting low-inductance undulatory galvanometer (SLUG) amplifier. The SLUG improves the system signal-to-noise ratio by 6.5 dB in a 20 MHz window compared with a bare high electron mobility transistor amplifier. An optimal cavity drive pulse is chosen using a genetic search algorithm, leading to a maximum combined readout and preparation fidelity of 91.9% with a measurement time of {{T}meas}=200 ns. Using post-selection to remove preparation errors caused by heating, we realize a combined preparation and readout fidelity of 94.3%.

  8. High-efficiency W-band hybrid integrated photoreceiver module using UTC-PD and pHEMT amplifier

    NASA Astrophysics Data System (ADS)

    Umezawa, T.; Katshima, K.; Kanno, A.; Akahane, K.; Matsumoto, A.; Yamamoto, N.; Kawanishi, T.

    2016-02-01

    A 100-GHz narrowband photoreceiver module integrated with a zero-bias operational uni-traveling-carrier photodiode (UTC-PD) and a GaAs-based pseudomorphic high-electron-mobility transistor (pHEMT) amplifier was fabricated and characterized. Both devices exhibited flat frequency response and outstanding overall performance. The UTC-PD showed a 3-dB bandwidth beyond 110 GHz while the pHEMT amplifier featured low power consumption and a gain of 24 dB over the 85-100 GHz range. A butterfly metal package equipped with a 1.0 mm (W) coaxial connector and a microstrip-coplanar waveguide conversion substrate was designed for low insertion loss and low return loss. The fabricated photoreceiver module demonstrated high conversion gain, a maximum output power of +9.5 dBm at 96 GHz, and DC-power consumption of 0.21 W.

  9. Multi-pass light amplifier

    NASA Technical Reports Server (NTRS)

    Plaessmann, Henry (Inventor); Grossman, William M. (Inventor); Olson, Todd E. (Inventor)

    1996-01-01

    A multiple-pass laser amplifier that uses optical focusing between subsequent passes through a single gain medium so that a reproducibly stable beam size is achieved within the gain region. A resonator or a White Cell cavity is provided, including two or more mirrors (planar or curvilinearly shaped) facing each other along a resonator axis and an optical gain medium positioned on a resonator axis between the mirrors or adjacent to one of the mirrors. In a first embodiment, two curvilinear mirrors, which may include adjacent lenses, are configured so that a light beam passing through the gain medium and incident on the first mirror is reflected by that mirror toward the second mirror in a direction approximately parallel to the resonator axis. A light beam translator, such as an optical flat of transparent material, is positioned to translate this light beam by a controllable amount toward or away from the resonator axis for each pass of the light beam through the translator. A second embodiment uses two curvilinear mirrors and one planar mirror, with a gain medium positioned in the optical path between each curvilinear mirror and the planar mirror. A third embodiment uses two curvilinear mirrors and two planar mirrors, with a gain medium positioned adjacent to a planar mirror. A fourth embodiment uses a curvilinear mirror and three planar mirrors, with a gain medium positioned adjacent to a planar mirror. A fourth embodiment uses four planar mirrors and a focusing lens system, with a gain medium positioned between the four mirrors. A fifth embodiment uses first and second planar mirrors, a focusing lens system and a third mirror that may be planar or curvilinear, with a gain medium positioned adjacent to the third mirror. A sixth embodiment uses two planar mirrors and a curvilinear mirror and a fourth mirror that may be planar or curvilinear, with a gain medium positioned adjacent to the fourth mirror. In a seventh embodiment, first and second mirrors face a third

  10. Operational Amplifier Experiments for the Chemistry Laboratory.

    ERIC Educational Resources Information Center

    Braun, Robert D.

    1996-01-01

    Provides details of experiments that deal with the use of operational amplifiers and are part of a course in instrumental analysis. These experiments are performed after the completion of a set of electricity and electronics experiments. (DDR)

  11. Microwave diode amplifiers with low intermodulation distortion

    NASA Technical Reports Server (NTRS)

    Cooper, H. W.; Cohn, M.; Buck, D. C.

    1975-01-01

    Distortions can be greatly reduced in narrow-band applications by using the second harmonic. The ac behavior of simplified diode amplifier has negative resistance depending on slope of equivalent I-V curve.

  12. Noise in phase-preserving linear amplifiers

    SciTech Connect

    Pandey, Shashank; Jiang, Zhang; Combes, Joshua; Caves, Carlton M.

    2014-12-04

    The purpose of a phase-preserving linear amplifier is to make a small signal larger, so that it can be perceived by instruments incapable of resolving the original signal, while sacrificing as little as possible in signal-to-noise. Quantum mechanics limits how well this can be done: the noise added by the amplifier, referred to the input, must be at least half a quantum at the operating frequency. This well-known quantum limit only constrains the second moments of the added noise. Here we provide the quantum constraints on the entire distribution of added noise: any phasepreserving linear amplifier is equivalent to a parametric amplifier with a physical state σ for the ancillary mode; σ determines the properties of the added noise.

  13. Integrated CMOS amplifier for ENG signal recording.

    PubMed

    Uranga, A; Navarro, X; Barniol, N

    2004-12-01

    The development and in vivo test of a fully integrated differential CMOS amplifier, implemented with standard 0.7-microm CMOS technology (one poly, two metals, self aligned twin-well CMOS process) intended to record extracellular neural signals is described. In order to minimize the flicker noise generated by the CMOS circuitry, a chopper technique has been chosen. The fabricated amplifier has a gain of 74 dB, a bandwidth of 3 kHz, an input noise of 6.6 nV/(Hz)0.5, a power dissipation of 1.3 mW, and the active area is 2.7 mm2. An ac coupling has been used to adapt the electrode to the amplifier circuitry for the in vivo testing. Compound muscle action potentials, motor unit action potentials, and compound nerve action potentials have been recorded in acute experiments with rats, in order to validate the amplifier. PMID:15605867

  14. Sensor/amplifier for weak light sources

    NASA Technical Reports Server (NTRS)

    Desmet, D. J.; Jason, A. J.; Parr, A. C.

    1980-01-01

    Light sensor/amplifier circuit detects weak light converts it into strong electrical signal in electrically noisy environment. Circuit is relatively simple and uses inexpensive, readily available components. Device is useful in such applications as fire detection and photographic processing.

  15. Two-stage hybrid microcircuit amplifier

    SciTech Connect

    Pyo, M.L.

    1987-04-01

    This report documents the design, development, and fabrication of a two-stage amplifier operating at 400 to 600 MHz. Included are characterization data, predictions generated during design, and measured performance.

  16. How to characterize the nonlinear amplifier?

    NASA Technical Reports Server (NTRS)

    Kallistratova, Dmitri Kouznetsov; Cotera, Carlos Flores

    1994-01-01

    The conception of the amplification of the coherent field is formulated. The definition of the coefficient of the amplification as the relation between the mean value of the field at the output to the value at the input and the definition of the noise as the difference between the number of photons in the output mode and square of the modulus of the mean value of the output amplitude are considered. Using a simple example it is shown that by these definitions the noise of the nonlinear amplifier may be less than the noise of the ideal linear amplifier of the same amplification coefficient. Proposals to search another definition of basic parameters of the nonlinear amplifiers are discussed. This definition should enable us to formulate the universal fundamental lower limit of the noise which should be valid for linear quantum amplifiers as for nonlinear ones.

  17. MMIC Amplifiers for 90 to 130 GHz

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Pukala, David; Peralta, Alejandro; Bryerton, Eric; Morgan, Matt; Boyd, T.; Hu, Ming; Schmitz, Adele

    2007-01-01

    This brief describes two monolithic microwave integrated-circuit (MMIC) amplifier chips optimized to function in the frequency range of 90 to 130 GHz, covering nearly all of F-band (90 - 140 GHz). These amplifiers were designed specifically for local-oscillator units in astronomical radio telescopes such as the Atacama Large Millimeter Array (ALMA). They could also be readily adapted for use in electronic test equipment, automotive radar systems, and communications systems that operate between 90 and 130 GHz.

  18. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon; Stock, Larry V.

    1989-01-01

    This semiannual progress report covers the period from September 1, 1988 to February 28, 1989 under NASA grant NAG-1-441 entitled, Direct Solar-Pumped Iodine Laser Amplifier. During this period, the research effort was concentrated on the solar pumped master oscillator power amplifier (MOPA) system using n-C3F7I. In the experimental work, the amplification measurement was conducted to identify the optimum conditions for amplification of the center's Vortek solar simulator pumped iodine laser amplifier. A modeling effort was also pursued to explain the experimental results in the theoretical work. The amplification measurement of the solar simulator pumped iodine laser amplifier is the first amplification experiment on the continuously pumped amplifier. The small signal amplification of 5 was achieved for the triple pass geometry of the 15 cm long solar simulator pumped amplifier at the n-C3F7I pressure of 20 torr, at the flow velocity of 6 m/sec and at the pumping intensity of 1500 solar constants. The XeCl laser pumped iodine laser oscillator, which was developed in the previous research, was employed as the master oscillator for the amplification measurement. In the theoretical work, the rate equations of the amplifier was established and the small signal amplification was calculated for the solar simulator pumped iodine laser amplifier. The amplification calculated from the kinetic equations with the previously measured rate coefficients reveals very large disagreement with experimental measurement. Moreover, the optimum condition predicted by the kinetic equation is quite discrepant with that measured by experiment. This fact indicates the necessity of study in the measurement of rate coefficients of the continuously pumped iodine laser system.

  19. High-Frequency, Conformable Organic Amplifiers.

    PubMed

    Reuveny, Amir; Lee, Sunghoon; Yokota, Tomoyuki; Fuketa, Hiroshi; Siket, Christian M; Lee, Sungwon; Sekitani, Tsuyoshi; Sakurai, Takayasu; Bauer, Siegfried; Someya, Takao

    2016-05-01

    Large-bandwidth, low-operation-voltage, and uniform organic amplifiers are fabricated on ultrathin foils. By the integration of short-channel OTFTs and AlOx capacitors, organic amplifiers with a bandwidth of 25 kHz are realized, demonstrating the highest gain-bandwidth product (GBWP) reported to date. Owing to material and process advancements, closed-loop architectures operate at frequencies of several kilohertz with an area smaller than 30 mm(2) . PMID:26922899

  20. High-Frequency, Conformable Organic Amplifiers.

    PubMed

    Reuveny, Amir; Lee, Sunghoon; Yokota, Tomoyuki; Fuketa, Hiroshi; Siket, Christian M; Lee, Sungwon; Sekitani, Tsuyoshi; Sakurai, Takayasu; Bauer, Siegfried; Someya, Takao

    2016-05-01

    Large-bandwidth, low-operation-voltage, and uniform organic amplifiers are fabricated on ultrathin foils. By the integration of short-channel OTFTs and AlOx capacitors, organic amplifiers with a bandwidth of 25 kHz are realized, demonstrating the highest gain-bandwidth product (GBWP) reported to date. Owing to material and process advancements, closed-loop architectures operate at frequencies of several kilohertz with an area smaller than 30 mm(2) .

  1. Athermal continuous-wave fiber amplifier

    NASA Astrophysics Data System (ADS)

    Nemova, Galina; Kashyap, Raman

    2009-07-01

    We present a new theoretical scheme for Yb 3+-doped athermal (radiation-balanced) continuous-wave fiber amplifier. This approach allows amplification with optical pumping of the fiber amplifier without detrimental heating of the fiber. Athermal amplification is realized by laser cooling in which waste heat is disposed of in the form of spontaneous fluorescence by balancing the radiated and absorbed power. The radiation-balanced fiber amplification can be realized using a specially designed distributed pumping scheme.

  2. Some Notes on Wideband Feedback Amplifiers

    DOE R&D Accomplishments Database

    Fitch, V.

    1949-03-16

    The extension of the passband of wideband amplifiers is a highly important problem to the designer of electronic circuits. Throughout the electronics industry and in many research programs in physics and allied fields where extensive use is made of video amplifiers, the foremost requirement is a passband of maximum width. This is necessary if it is desired to achieve a more faithful reproduction of transient wave forms, a better time resolution in physical measurements, or perhaps just a wider band gain-frequency response to sine wave signals. The art of electronics is continually faced with this omnipresent amplifier problem. In particular, the instrumentation techniques of nuclear physics require amplifiers with short rise times, a high degree of gain stability, and a linear response to high signal levels. While the distributed amplifier may solve the problems of those seeking only a wide passband, the requirements of stability and linearity necessitate using feedback circuits. This paper considers feedback amplifiers from the standpoint of high-frequency performance. The circuit conditions for optimum steady-state (sinusoidal) and transient response are derived and practical circuits (both interstage and output) are presented which fulfill these conditions. In general, the results obtained may be applied to the low-frequency end.

  3. V-band IMPATT power amplifier

    NASA Technical Reports Server (NTRS)

    Schell, S. W.

    1985-01-01

    This program is the result of the continuing demand and future requirement for a high data rate 60-GHz communications link. A reliable solid-state transmitter which delivers the necessary power over a wide bandwidth using the present IMPATT diode technology required the development of combining techniques. The development of a 60-GHz IMPATT power combiner amplifier is detailed. The results form a basis from which future wideband, high-power IMPATT amplifiers may be developed. As a result, several state-of-the-art advancements in millimeter-wave components technology were achieved. Specific achievements for the amplifier integration were: development of a nonresonant divider/combiner circuit; reproducible multiple junction circulator assemblies; and reliable high power 60-GHz IMPATT diodes. The various design approaches and tradeoffs which lead to the final amplifier configuration are discussed. A detailed circuit design is presented for the various amplifier components, and the conical line combiner, radial line combiner, and circulator development are discussed. The performance of the amplifier, the overall achievement of the program, the implications of the results, and an assessment of future development needs and recommendations are examined.

  4. Multiple excitation regenerative amplifier inertial confinement system

    DOEpatents

    George, V.E.; Haas, R.A.; Krupke, W.F.; Schlitt, L.G.

    1980-05-27

    The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation. 11 figs.

  5. Multiple excitation regenerative amplifier inertial confinement system

    DOEpatents

    George, Victor E. [Livermore, CA; Haas, Roger A. [Pleasanton, CA; Krupke, William F. [Pleasanton, CA; Schlitt, Leland G. [Livermore, CA

    1980-05-27

    The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation.

  6. Proposal of Switching Power Amplifier Using Small Capacity Linear Amplifier and LC Filter

    NASA Astrophysics Data System (ADS)

    Kamada, Jo; Funato, Hirohito; Ogasawara, Satoshi

    The higher efficiency and the low noise in output voltage and current has been required in some applications, i.e. audio-video equipment, medical equipment and so on. This paper proposes a power amplifier in which a PWM inverter is used as a main circuit. In the proposed power amplifier, a hybrid filter composed of a simple and general LC filter and a small capacity linear amplifier is connected to the output of the inverter. The linear amplifier is inserted in series to the filter capacitor to improve the filtering effect of the LC filter. Switching ripples and LC resonances are considerably suppressed by controlling the amplifier using the proposed method and a low distortion switching power amplifier is realized. The effects of the proposal circuit are verified by simulations and experiments. As a result, the proposed circuit achieves low noise about THD=0.68% in simulation and THD=1.7% in experiment.

  7. The 'SuperFET' - A monolithic device for high-gain amplifiers

    NASA Astrophysics Data System (ADS)

    Crescenzi, E. J., Jr.; Wilser, W. T.; Oglesbee, R. W.; Algeri, S. J.

    1981-07-01

    The development of minimum area GaAs FET chips which resulted in ICs with two FETs on a single .7 sq mm chip linked with microstrip matching circuitry is described. Cost considerations are given, noting that the figure of merit was high due to matching elements covering over half of the total chip area. The gain for the X- and Ku-bands over discrete transistors were 6 and 5 dB, at 20 and 18 GHz respectively. Design objectives for the X-band IC of 7-12.5 GHz minimum bandwidth, multistage cascadability for amplifier gains in the 25 to 50 dB range, low VSWR gain flatness, and cost competitiveness with thin film discrete FETs were achieved. The Ku-band 'superFET' was designed for small size, application flexibility, and mechanical ruggedness and reliability, with an eye to EW military applications.

  8. First On-Wafer Power Characterization of MMIC Amplifiers at Sub-Millimeter Wave Frequencies

    NASA Technical Reports Server (NTRS)

    Fung, A. K.; Gaier, T.; Samoska, L.; Deal, W. R.; Radisic, V.; Mei, X. B.; Yoshida, W.; Liu, P. S.; Uyeda, J.; Barsky, M.; Lai, R.

    2008-01-01

    Recent developments in semiconductor technology have enabled advanced submillimeter wave (300 GHz) transistors and circuits. These new high speed components have required new test methods to be developed for characterizing performance, and to provide data for device modeling to improve designs. Current efforts in progressing high frequency testing have resulted in on-wafer-parameter measurements up to approximately 340 GHz and swept frequency vector network analyzer waveguide measurements to 508 GHz. On-wafer noise figure measurements in the 270-340 GHz band have been demonstrated. In this letter we report on on-wafer power measurements at 330 GHz of a three stage amplifier that resulted in a maximum measured output power of 1.78mW and maximum gain of 7.1 dB. The method utilized demonstrates the extension of traditional power measurement techniques to submillimeter wave frequencies, and is suitable for automated testing without packaging for production screening of submillimeter wave circuits.

  9. Three-Stage InP Submillimeter-Wave MMIC Amplifier

    NASA Technical Reports Server (NTRS)

    Pukala, David; Samoska, Lorene; Man, King; Gaier, Todd; Deal, William; Lai, Richard; Mei, Gerry; Makishi, Stella

    2008-01-01

    A submillimeter-wave monolithic integrated- circuit (S-MMIC) amplifier has been designed and fabricated using an indium phosphide (InP) 35-nm gate-length high electron mobility transistor (HEMT) device, developed at Northrop Grumman Corporation. The HEMT device employs two fingers each 15 micrometers wide. The HEMT wafers are grown by molecular beam epitaxy (MBE) and make use of a pseudomorphic In0.75Ga0.25As channel, a silicon delta-doping layer as the electron supply, an In0.52Al0.48As buffer layer, and an InP substrate. The three-stage design uses coplanar waveguide topology with a very narrow ground-to-ground spacing of 14 micrometers. Quarter-wave matching transmission lines, on-chip metal-insulator-metal shunt capacitors, series thin-film resistors, and matching stubs were used in the design. Series resistors in the shunt branch arm provide the basic circuit stabilization. The S-MMIC amplifier was measured for S-parameters and found to be centered at 320 GHz with 13-15-dB gain from 300-345 GHz. This chip was developed as part of the DARPA Submillimeter Wave Imaging Focal Plane Technology (SWIFT) program (see figure). Submillimeter-wave amplifiers could enable more sensitive receivers for earth science, planetary remote sensing, and astrophysics telescopes, particularly in radio astronomy, both from the ground and in space. A small atmospheric window at 340 GHz exists and could enable ground-based observations. However, the submillimeter-wave regime (above 300 GHz) is best used for space telescopes as Earth s atmosphere attenuates most of the signal through water and oxygen absorption. Future radio telescopes could make use of S-MMIC amplifiers for wideband, low noise, instantaneous frequency coverage, particularly in the case of heterodyne array receivers.

  10. Real Time Calibration Method for Signal Conditioning Amplifiers

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J. (Inventor); Mata, Carlos T. (Inventor); Eckhoff, Anthony (Inventor); Perotti, Jose (Inventor); Lucena, Angel (Inventor)

    2004-01-01

    A signal conditioning amplifier receives an input signal from an input such as a transducer. The signal is amplified and processed through an analog to digital converter and sent to a processor. The processor estimates the input signal provided by the transducer to the amplifier via a multiplexer. The estimated input signal is provided as a calibration voltage to the amplifier immediately following the receipt of the amplified input signal. The calibration voltage is amplified by the amplifier and provided to the processor as an amplified calibration voltage. The amplified calibration voltage is compared to the amplified input signal, and if a significant error exists, the gain and/or offset of the amplifier may be adjusted as necessary.

  11. A silicon nanocrystal tunnel field effect transistor

    SciTech Connect

    Harvey-Collard, Patrick; Drouin, Dominique; Pioro-Ladrière, Michel

    2014-05-12

    In this work, we demonstrate a silicon nanocrystal Field Effect Transistor (ncFET). Its operation is similar to that of a Tunnelling Field Effect Transistor (TFET) with two barriers in series. The tunnelling barriers are fabricated in very thin silicon dioxide and the channel in intrinsic polycrystalline silicon. The absence of doping eliminates the problem of achieving sharp doping profiles at the junctions, which has proven a challenge for large-scale integration and, in principle, allows scaling down the atomic level. The demonstrated ncFET features a 10{sup 4} on/off current ratio at room temperature, a low 30 pA/μm leakage current at a 0.5 V bias, an on-state current on a par with typical all-Si TFETs and bipolar operation with high symmetry. Quantum dot transport spectroscopy is used to assess the band structure and energy levels of the silicon island.

  12. Vertically Integrated Multiple Nanowire Field Effect Transistor.

    PubMed

    Lee, Byung-Hyun; Kang, Min-Ho; Ahn, Dae-Chul; Park, Jun-Young; Bang, Tewook; Jeon, Seung-Bae; Hur, Jae; Lee, Dongil; Choi, Yang-Kyu

    2015-12-01

    A vertically integrated multiple channel-based field-effect transistor (FET) with the highest number of nanowires reported ever is demonstrated on a bulk silicon substrate without use of wet etching. The driving current is increased by 5-fold due to the inherent vertically stacked five-level nanowires, thus showing good feasibility of three-dimensional integration-based high performance transistor. The developed fabrication process, which is simple and reproducible, is used to create multiple stiction-free and uniformly sized nanowires with the aid of the one-route all-dry etching process (ORADEP). Furthermore, the proposed FET is revamped to create nonvolatile memory with the adoption of a charge trapping layer for enhanced practicality. Thus, this research suggests an ultimate design for the end-of-the-roadmap devices to overcome the limits of scaling.

  13. Radiation effects on power transistor performance

    NASA Technical Reports Server (NTRS)

    Frasca, Albert J.

    1987-01-01

    The D60T, D62T, and D75T transistors in the nuclear reactor were irradiated with bias voltage and high current I sub c vs. V sub ec curves were obtained to evaluate gain degradation at high power levels. Pre- and post-irradiation high current switching tests were performed to evaluate the response. The gamma ray damage work done at Sandia was correlated with the neutron work done at the O.S.U. reactor with the above specified transistors. Theoretical analyses of damage and electrical performance were conducted in terms of semiconductor physics. The experimental high current pulser was improved in order to measure switching time changes which are less than one microsecond at currents of 100 to 200 amperes for in-situ testing.

  14. Flexible Organic Transistors with Controlled Nanomorphology.

    PubMed

    Lee, Byoung Hoon; Hsu, Ben B Y; Patel, Shrayesh N; Labram, John; Luo, Chan; Bazan, Guillermo C; Heeger, Alan J

    2016-01-13

    We report the controlled nanomorphology of semiconducting polymers on chemically and mechanically stable nanogrooved polymer substrates. By employing silicon dioxide thin films with finely adjusted thicknesses on nanogrooved polymer substrates, semiconducting polymer thin films oriented and aligned along the nanogrooves were obtained. Organic field-effect transistors (OFETs) fabricated from the oriented semiconducting polymer, poly[4-(4,4-dihexadecyl-4H-cyclopenta[1,2-b:5,4-b']dithiophen-2-yl)-alt-[1,2,5]thiadiazolo-[3,4-c]pyridine] (PCDTPT), yielded saturation hole mobilities as high as 19.3 cm(2) V(-1 )s(-1), and the flexible "plastic" transistors demonstrated excellent mechanical stability under various bending conditions. These results represent important progress for solution-processed flexible OFETs and demonstrate that directed self-assembly of semiconducting polymers can be achieved by soft nanostructures. PMID:26645364

  15. Vertically Integrated Multiple Nanowire Field Effect Transistor.

    PubMed

    Lee, Byung-Hyun; Kang, Min-Ho; Ahn, Dae-Chul; Park, Jun-Young; Bang, Tewook; Jeon, Seung-Bae; Hur, Jae; Lee, Dongil; Choi, Yang-Kyu

    2015-12-01

    A vertically integrated multiple channel-based field-effect transistor (FET) with the highest number of nanowires reported ever is demonstrated on a bulk silicon substrate without use of wet etching. The driving current is increased by 5-fold due to the inherent vertically stacked five-level nanowires, thus showing good feasibility of three-dimensional integration-based high performance transistor. The developed fabrication process, which is simple and reproducible, is used to create multiple stiction-free and uniformly sized nanowires with the aid of the one-route all-dry etching process (ORADEP). Furthermore, the proposed FET is revamped to create nonvolatile memory with the adoption of a charge trapping layer for enhanced practicality. Thus, this research suggests an ultimate design for the end-of-the-roadmap devices to overcome the limits of scaling. PMID:26544156

  16. Black phosphorus field-effect transistors.

    PubMed

    Li, Likai; Yu, Yijun; Ye, Guo Jun; Ge, Qingqin; Ou, Xuedong; Wu, Hua; Feng, Donglai; Chen, Xian Hui; Zhang, Yuanbo

    2014-05-01

    Two-dimensional crystals have emerged as a class of materials that may impact future electronic technologies. Experimentally identifying and characterizing new functional two-dimensional materials is challenging, but also potentially rewarding. Here, we fabricate field-effect transistors based on few-layer black phosphorus crystals with thickness down to a few nanometres. Reliable transistor performance is achieved at room temperature in samples thinner than 7.5 nm, with drain current modulation on the order of 10(5) and well-developed current saturation in the I-V characteristics. The charge-carrier mobility is found to be thickness-dependent, with the highest values up to ∼ 1,000 cm(2) V(-1) s(-1) obtained for a thickness of ∼ 10 nm. Our results demonstrate the potential of black phosphorus thin crystals as a new two-dimensional material for applications in nanoelectronic devices.

  17. Ballistic InAs nanowire transistors.

    PubMed

    Chuang, Steven; Gao, Qun; Kapadia, Rehan; Ford, Alexandra C; Guo, Jing; Javey, Ali

    2013-02-13

    Ballistic transport of electrons at room temperature in top-gated InAs nanowire (NW) transistors is experimentally observed and theoretically examined. From length dependent studies, the low-field mean free path is directly extracted as ~150 nm. The mean free path is found to be independent of temperature due to the dominant role of surface roughness scattering. The mean free path was also theoretically assessed by a method that combines Fermi's golden rule and a numerical Schrödinger-Poisson simulation to determine the surface scattering potential with the theoretical calculations being consistent with experiments. Near ballistic transport (~80% of the ballistic limit) is demonstrated experimentally for transistors with a channel length of ~60 nm, owing to the long mean free path of electrons in InAs NWs. PMID:23256503

  18. Gold-coated graphene field-effect transistors for quantitative analysis of protein-antibody interactions

    NASA Astrophysics Data System (ADS)

    Tarasov, Alexey; Tsai, Meng-Yen; Flynn, Erin M.; Joiner, Corey A.; Taylor, Robert C.; Vogel, Eric M.

    2015-12-01

    Field-effect transistors (FETs) based on large-area graphene and other 2D materials can potentially be used as low-cost and flexible potentiometric biological sensors. However, there have been few attempts to use these devices for quantifying molecular interactions and to compare their performance to established sensor technology. Here, gold-coated graphene FETs are used to measure the binding affinity of a specific protein-antibody interaction. Having a gold surface gives access to well-known thiol chemistry for the self-assembly of linker molecules. The results are compared with potentiometric silicon-based extended-gate sensors and a surface plasmon resonance system. The estimated dissociation constants are in excellent agreement for all sensor types as long as the active surfaces are the same (gold). The role of the graphene transducer is to simply amplify surface potential changes caused by adsorption of molecules on the gold surface.

  19. Device and Design Optimization for AlGaN/GaN X-Band-Power-Amplifiers with High Efficiency

    NASA Astrophysics Data System (ADS)

    Kühn, Jutta; van Raay, Friedbert; Quay, Rüdiger; Kiefer, Rudolf; Mikulla, Michael; Seelmann-Eggebert, Matthias; Bronner, Wolfgang; Schlechtweg, Michael; Ambacher, Oliver; Thumm, Manfred

    2010-03-01

    The design, realization and characterization of dual-stage X-band high-power and highly-efficient monolithic microwave integrated circuit (MMIC) power amplifiers (PAs) with AlGaN/GaN high electronic mobility transistors (HEMTs) is presented. These high power amplifiers (HPAs) are based on a precise investigation of circuit-relevant HEMT behavior using two different field-plate variants and its effects on PA performance as well as optimization of HPA driver stage size which also has a deep impact on the entire HPA. Two broadband (3 GHz) MMICs with different field-plate variants and two narrowband (1 GHz) PAs with different driver- to final-stage gate-width ratio are realized with a maximum output power of 19-23 W, a maximum power-added efficiency (PAE) of ≥40%, and an associated power gain of 17 dB at X-band. Furthermore, two 1 mm test transistors of the same technology with the mentioned field-plate variants and a 1 mm test MMIC support VSWR-ratio tests of 6:1 and 4:1, respectively.

  20. Nonuniform carrier distribution in semiconductor optical amplifiers

    NASA Astrophysics Data System (ADS)

    Evankow, Joseph David, Jr.

    This work discusses the experimental results and theoretical analysis of the longitudinal distribution of the spontaneous emission, amplified spontaneous emission, hole-electron pairs, and gain in semiconductor optical amplifiers. A novel, yet simple, technique was developed enabling, for the first time, the measurement of these distributions. This was accomplished with a high degree of spatial resolution using a single-mode micro-lensed fiber tip positioned perpendicular to the active region and moved longitudinally along the stripe. The cornerstone of this study centers on the theoretical analysis of the small portion of the isotropic spontaneous emission, emanating from the optical cavity, which is captured by the lensed fiber. Spectral as well as integrated power measurements were made along the length of the cavity. These spectral and integrated power measurements provide a direct link to the carrier concentration and gain along the optical cavity. The distribution of this spontaneous emission along the amplifier, and its relationship to other parameters, provide information about the carriers. Since the common mode of operation for linear optical amplifiers is deep in saturation, the devices in this study were analyzed in regimes significantly below the small-signal gain. While large carrier density non- uniformity occur with output powers equal to or greater than Psat, a significant amount can occur in amplifiers even with small input signals. In these amplifiers, the higher carder concentrations produce much higher internal gain coefficients making them more prone to non-uniform carrier density distributions. Moreover, even in semiconductor lasers, where the carrier concentration and the gain are pinned at the onset of lasing to rather pedestrian levels (approximately 1 × 1018 cm-3 and of 3 dB, respectively), previous theoretical analysis for more than a decade postulated that a significant spatial distribution occur. These measurements and analysis

  1. Npn double heterostructure bipolar transistor with ingaasn base region

    DOEpatents

    Chang, Ping-Chih; Baca, Albert G.; Li, Nein-Yi; Hou, Hong Q.; Ashby, Carol I. H.

    2004-07-20

    An NPN double heterostructure bipolar transistor (DHBT) is disclosed with a base region comprising a layer of p-type-doped indium gallium arsenide nitride (InGaAsN) sandwiched between n-type-doped collector and emitter regions. The use of InGaAsN for the base region lowers the transistor turn-on voltage, V.sub.on, thereby reducing power dissipation within the device. The NPN transistor, which has applications for forming low-power electronic circuitry, is formed on a gallium arsenide (GaAs) substrate and can be fabricated at commercial GaAs foundries. Methods for fabricating the NPN transistor are also disclosed.

  2. Free electron gas primary thermometer: The bipolar junction transistor

    SciTech Connect

    Mimila-Arroyo, J.

    2013-11-04

    The temperature of a bipolar transistor is extracted probing its carrier energy distribution through its collector current, obtained under appropriate polarization conditions, following a rigorous mathematical method. The obtained temperature is independent of the transistor physical properties as current gain, structure (Homo-junction or hetero-junction), and geometrical parameters, resulting to be a primary thermometer. This proposition has been tested using off the shelf silicon transistors at thermal equilibrium with water at its triple point, the transistor temperature values obtained involve an uncertainty of a few milli-Kelvin. This proposition has been successfully tested in the temperature range of 77–450 K.

  3. Optical driven electromechanical transistor based on tunneling effect.

    PubMed

    Jin, Leisheng; Li, Lijie

    2015-04-15

    A new electromechanical transistor based on an optical driven vibrational ring structure has been postulated. In the device, optical power excites the ring structure to vibrate, which acts as the shuttle transporting electrons from one electrode to the other forming the transistor. The electrical current of the transistor is adjusted by the optical power. Coupled opto-electro-mechanical simulation has been performed. It is shown from the dynamic analysis that the stable working range of the transistor is much wider than that of the optical wave inside the cavity, i.e., the optical resonance enters nonperiodic states while the mechanical vibration of the ring is still periodic.

  4. A PWM transistor inverter for an ac electric vehicle drive

    NASA Technical Reports Server (NTRS)

    Slicker, J. M.

    1981-01-01

    A prototype system consisting of closely integrated motor, inverter, and transaxle has been built in order to demonstrate the feasibility of a three-phase ac transistorized inverter for electric vehicle applications. The microprocessor-controlled inverter employs monolithic power transistors to drive an oil-cooled, three-phase induction traction motor at a peak output power of 30 kW from a 144 V battery pack. Transistor safe switching requirements are discussed, and a circuit is presented for recovering trapped snubber inductor energy at transistor turn-off.

  5. A circuit model for defective bilayer graphene transistors

    NASA Astrophysics Data System (ADS)

    Umoh, Ime J.; Moktadir, Zakaria; Hang, Shuojin; Kazmierski, Tom J.; Mizuta, Hiroshi

    2016-05-01

    This paper investigates the behaviour of a defective single-gate bilayer graphene transistor. Point defects were introduced into pristine graphene crystal structure using a tightly focused helium ion beam. The transfer characteristics of the exposed transistors were measured ex-situ for different defect concentrations. The channel peak resistance increased with increasing defect concentration whilst the on-off ratio showed a decreasing trend for both electrons and holes. To understand the electrical behaviour of the transistors, a circuit model for bilayer graphene is developed which shows a very good agreement when validated against experimental data. The model allowed parameter extraction of bilayer transistor and can be implemented in circuit level simulators.

  6. Flexible polymer transistors with high pressure sensitivity for application in electronic skin and health monitoring

    NASA Astrophysics Data System (ADS)

    Schwartz, Gregor; Tee, Benjamin C.-K.; Mei, Jianguo; Appleton, Anthony L.; Kim, Do Hwan; Wang, Huiliang; Bao, Zhenan

    2013-05-01

    Flexible pressure sensors are essential parts of an electronic skin to allow future biomedical prostheses and robots to naturally interact with humans and the environment. Mobile biomonitoring in long-term medical diagnostics is another attractive application for these sensors. Here we report the fabrication of flexible pressure-sensitive organic thin film transistors with a maximum sensitivity of 8.4 kPa-1, a fast response time of <10 ms, high stability over >15,000 cycles and a low power consumption of <1 mW. The combination of a microstructured polydimethylsiloxane dielectric and the high-mobility semiconducting polyisoindigobithiophene-siloxane in a monolithic transistor design enabled us to operate the devices in the subthreshold regime, where the capacitance change upon compression of the dielectric is strongly amplified. We demonstrate that our sensors can be used for non-invasive, high fidelity, continuous radial artery pulse wave monitoring, which may lead to the use of flexible pressure sensors in mobile health monitoring and remote diagnostics in cardiovascular medicine.

  7. Design and simulation of oxide and doping engineered lateral bipolar junction transistors for high power applications

    NASA Astrophysics Data System (ADS)

    Loan, Sajad A.; Bashir, Faisal; Akhoon, M. Saqib; Alamoud, Abdulrahman M.

    2016-01-01

    In this paper, we propose new structures of lateral bipolar junction transistor (LBJT) on silicon on insulator (SOI) with improved performance. The proposed devices are lateral bipolar transistors with multi doping zone collector drift region and a thick buried oxide under the collector region. Calibrated simulation studies have revealed that the proposed devices have higher breakdown voltage than the conventional device, that too at higher drift doping concentration. This has resulted in improved tradeoff between the on-resistance and the breakdown voltage of the proposed devices. It has been observed that the proposed device with two collector drift doping zones and a buried oxide thick step results in ∼190% increase in the breakdown voltage than the conventional device. The further increase in the number of collector drift doping zones from two to three has increased the breakdown voltage by 260% than the conventional one. On comparing the proposed devices with the buried oxide double step devices, it has been found that an increase of ∼15-19% in the breakdown voltage is observed in the proposed devices even at higher drift doping concentrations. The use of higher drift doping concentration reduces the on-resistance of the proposed device and thus improves the tradeoff between the breakdown voltage and the on-resistance of the proposed device in comparison to buried oxide double step devices. Further, the use of step doping in the collector drift region has resulted in the reduction of kink effect in the proposed device. Using the mixed mode simulations, the proposed devices have been tested at the circuit level, by designing and simulating inverting amplifiers employing the proposed devices. Both DC and AC analyses of the inverting amplifiers have shown that the proposed devices work well at the circuit level. It has been observed that there is a slight increase in ON delay in the proposed device; however, the OFF delay is more or less same as that of the

  8. Thermal recovery of the NIF amplifiers

    SciTech Connect

    Beullier, J; Bicrel,; Erlandson, A; London, R; Manes, K; Marshall, C; Petty, C; Pierce, R; Smith, L; Sutton, S; Zapata, L

    1998-06-30

    With approximately 99% of the electrical energy supplied to the National Ignition Facility (NIF) appearing as heat in the amplifiers, thermal recovery of the NIF system is a major consideration in the design process. The NIF shot rate is one shot every 8 hours, with a goal of 4 hours between shots. This necessitates that thermal recovery take place in no more than 7 hours, with a goal of 3 hours for the accelerated shot rate. Residual optical distortions, which restrict the shot rate, are grouped into two discrete categories: (1) distortions associated with residual temperature gradients in the laser slabs, and (2) distortions associated with buoyantly driven convective currents in the amplifier cavity and beam-tube regions. Thermal recovery of the amplifiers is achieved by cooling the flashlamps and blastshields with a turbulent gas flow. The cooled blastshields then serve as a cold boundary to radiatively extract the residual heat deposited in the slabs and edge claddings. Advanced concepts, such as the use of slightly chilled gas to accelerate some aspects of recovery, are addressed. To quantify recovery rates of the amplifiers, experiments and numerical models are used to measure and calculate the temperatures and optical distortions in NIF-like amplifier elements. The calculation results are benchmarked against AMLAB temperature measurements, thus allowing a quantitative prediction of NIF thermal recovery. These results indicate that the NIF requirement of 7 hour thermal recovery can be achieved with chilled temperature cooling gas.

  9. High power, high beam quality regenerative amplifier

    DOEpatents

    Hackel, Lloyd A.; Dane, Clifford B.

    1993-01-01

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  10. High power, high beam quality regenerative amplifier

    DOEpatents

    Hackel, L.A.; Dane, C.B.

    1993-08-24

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  11. Injection- Seeded Optoplasmonic Amplifier in the Visible

    PubMed Central

    Gartia, Manas Ranjan; Seo, Sujin; Kim, Junhwan; Chang, Te-Wei; Bahl, Gaurav; Lu, Meng; Liu, Gang Logan; Eden, J. Gary

    2014-01-01

    A hybrid optoplasmonic amplifier, injection-seeded by an internally-generated Raman signal and operating in the visible (563–675 nm), is proposed and evidence for amplification is presented. Comprising a gain medium tethered to a whispering gallery mode (WGM) resonator with a protein, and a plasmonic surface, the optical system described here selectively amplifies a single (or a few) Raman line(s) produced within the WGM resonator and is well-suited for routing narrowband optical power on-a-chip. Over the past five decades, optical oscillators and amplifiers have typically been based on the buildup of the field from the spontaneous emission background. Doing so limits the temporal coherence of the output, lengthens the time required for the optical field intensity to reach saturation, and often is responsible for complex, multiline spectra. In addition to the spectral control afforded by injection-locking, the effective Q of the amplifier can be specified by the bandwidth of the injected Raman signal. This characteristic contrasts with previous WGM-based lasers and amplifiers for which the Q is determined solely by the WGM resonator. PMID:25156810

  12. Method to amplify variable sequences without imposing primer sequences

    DOEpatents

    Bradbury, Andrew M.; Zeytun, Ahmet

    2006-11-14

    The present invention provides methods of amplifying target sequences without including regions flanking the target sequence in the amplified product or imposing amplification primer sequences on the amplified product. Also provided are methods of preparing a library from such amplified target sequences.

  13. Ultrashort pulse amplification in cryogenically cooled amplifiers

    DOEpatents

    Backus, Sterling J.; Kapteyn, Henry C.; Murnane, Margaret Mary

    2004-10-12

    A laser amplifier system amplifies pulses in a single "stage" from .about.10.sup.-9 joules to more than 10.sup.-3 joules, with average power of 1-10 watts, and beam quality M.sup.2 <2. The laser medium is cooled substantially below room temperature, as a means to improve the optical and thermal characteristics of the medium. This is done with the medium inside a sealed, evacuated or purged cell to avoid moisture or other materials condensing on the surface. A "seed" pulse from a separate laser is passed through the laser medium, one or more times, in any of a variety of configurations including single-pass, multiple-pass, and regenerative amplifier configurations.

  14. Modulation instability in high power laser amplifiers.

    PubMed

    Rubenchik, Alexander M; Turitsyn, Sergey K; Fedoruk, Michail P

    2010-01-18

    The modulation instability (MI) is one of the main factors responsible for the degradation of beam quality in high-power laser systems. The so-called B-integral restriction is commonly used as the criteria for MI control in passive optics devices. For amplifiers the adiabatic model, assuming locally the Bespalov-Talanov expression for MI growth, is commonly used to estimate the destructive impact of the instability. We present here the exact solution of MI development in amplifiers. We determine the parameters which control the effect of MI in amplifiers and calculate the MI growth rate as a function of those parameters. The safety range of operational parameters is presented. The results of the exact calculations are compared with the adiabatic model, and the range of validity of the latest is determined. We demonstrate that for practical situations the adiabatic approximation noticeably overestimates MI. The additional margin of laser system design is quantified.

  15. Ultraflexible organic amplifier with biocompatible gel electrodes.

    PubMed

    Sekitani, Tsuyoshi; Yokota, Tomoyuki; Kuribara, Kazunori; Kaltenbrunner, Martin; Fukushima, Takanori; Inoue, Yusuke; Sekino, Masaki; Isoyama, Takashi; Abe, Yusuke; Onodera, Hiroshi; Someya, Takao

    2016-01-01

    In vivo electronic monitoring systems are promising technology to obtain biosignals with high spatiotemporal resolution and sensitivity. Here we demonstrate the fabrication of a biocompatible highly conductive gel composite comprising multi-walled carbon nanotube-dispersed sheet with an aqueous hydrogel. This gel composite exhibits admittance of 100 mS cm(-2) and maintains high admittance even in a low-frequency range. On implantation into a living hypodermal tissue for 4 weeks, it showed a small foreign-body reaction compared with widely used metal electrodes. Capitalizing on the multi-functional gel composite, we fabricated an ultrathin and mechanically flexible organic active matrix amplifier on a 1.2-μm-thick polyethylene-naphthalate film to amplify (amplification factor: ∼200) weak biosignals. The composite was integrated to the amplifier to realize a direct lead epicardial electrocardiography that is easily spread over an uneven heart tissue. PMID:27125910

  16. The Electron Beam Semiconductor (EBS) amplifier

    NASA Astrophysics Data System (ADS)

    True, R. M.; Baxendale, J. F.

    1980-07-01

    The Electron Beam Semiconductor (EBS) concept has existed for three decades; but only within the last decade has an active, well-defined program been underway to develop devices that can operate as high-power radio frequency(RF) amplifiers, fast risetime switches, and current and voltage pulse amplifiers. This report discusses the test procedures, data and results of reliability testing of RF and video pulse EBS amplifiers at Electronics Research and Development Command (ERADCOM), Fort Monmouth, New Jersey. Also, the experimental analysis of the series connected diode EBS device is described in detail. Finally, the report concludes with a discussion of the state-of-the-art of EBS and future trends of the technology.

  17. Ultraflexible organic amplifier with biocompatible gel electrodes

    NASA Astrophysics Data System (ADS)

    Sekitani, Tsuyoshi; Yokota, Tomoyuki; Kuribara, Kazunori; Kaltenbrunner, Martin; Fukushima, Takanori; Inoue, Yusuke; Sekino, Masaki; Isoyama, Takashi; Abe, Yusuke; Onodera, Hiroshi; Someya, Takao

    2016-04-01

    In vivo electronic monitoring systems are promising technology to obtain biosignals with high spatiotemporal resolution and sensitivity. Here we demonstrate the fabrication of a biocompatible highly conductive gel composite comprising multi-walled carbon nanotube-dispersed sheet with an aqueous hydrogel. This gel composite exhibits admittance of 100 mS cm-2 and maintains high admittance even in a low-frequency range. On implantation into a living hypodermal tissue for 4 weeks, it showed a small foreign-body reaction compared with widely used metal electrodes. Capitalizing on the multi-functional gel composite, we fabricated an ultrathin and mechanically flexible organic active matrix amplifier on a 1.2-μm-thick polyethylene-naphthalate film to amplify (amplification factor: ~200) weak biosignals. The composite was integrated to the amplifier to realize a direct lead epicardial electrocardiography that is easily spread over an uneven heart tissue.

  18. FEL amplifier performance in the Compton regime

    NASA Astrophysics Data System (ADS)

    Cover, R. A.; Bhowmik, A.

    1984-01-01

    The Kroll-Morton-Rosenbluth equations of motion for electrons in a linearly polarized, tapered wiggler are utilized to describe gain in free-electron laser amplifiers. The three-dimensional amplifier model includes the effects of density variation in the electron beam, off-axis variations in the wiggler magnetic field, and betatron oscillations. The input electromagnetic field is injected and subsequently propagated within the wiggler by computing the Fresnel-Kirchhoff diffraction integral using the Gardner-Fresnel-Kirchhoff algorithm. The injected optical beam used in evaluating amplifier performance is initially a Gaussian which in general may be astigmatic. The importance of the above effects on extraction efficiency is computed both with rigorous three-dimensional electromagnetic wave propagation and a Gaussian treatment of the field.

  19. Single mode terahertz quantum cascade amplifier

    SciTech Connect

    Ren, Y. Wallis, R.; Shah, Y. D.; Jessop, D. S.; Degl'Innocenti, R.; Klimont, A.; Kamboj, V.; Beere, H. E.; Ritchie, D. A.

    2014-10-06

    A terahertz (THz) optical amplifier based on a 2.9 THz quantum cascade laser (QCL) structure has been demonstrated. By depositing an antireflective coating on the QCL facet, the laser mirror losses are enhanced to fully suppress the lasing action, creating a THz quantum cascade (QC) amplifier. Terahertz radiation amplification has been obtained, by coupling a separate multi-mode THz QCL of the same active region design to the QC amplifier. A bare cavity gain is achieved and shows excellent agreement with the lasing spectrum from the original QCL without the antireflective coating. Furthermore, a maximum optical gain of ∼30 dB with single-mode radiation output is demonstrated.

  20. Short pulse free electron laser amplifier

    DOEpatents

    Schlitt, Leland G.; Szoke, Abraham

    1985-01-01

    Method and apparatus for amplification of a laser pulse in a free electron laser amplifier where the laser pulse duration may be a small fraction of the electron beam pulse duration used for amplification. An electron beam pulse is passed through a first wiggler magnet and a short laser pulse to be amplified is passed through the same wiggler so that only the energy of the last fraction, f, (f<1) of the electron beam pulse is consumed in amplifying the laser pulse. After suitable delay of the electron beam, the process is repeated in a second wiggler magnet, a third, . . . , where substantially the same fraction f of the remainder of the electron beam pulse is consumed in amplification of the given short laser pulse in each wiggler magnet region until the useful electron beam energy is substantially completely consumed by amplification of the laser pulse.

  1. High Bandwidth Differential Amplifier for Shock Experiments

    SciTech Connect

    Ross, P. W., Tran, V., Chau, R.

    2012-04-30

    We developed a high bandwidth differential amplifier for gas gun shock experiments/applications. The circuit has a bandwidth > 1 GHz, and is capable of measuring signals of ≤1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is approximately 250 V relative to ground. Since the expected voltage change in the target is < 1 V, the differential amplifier must have a large common mode rejection. High pass filters suppress internal ringing of operational amplifiers. Results of bench tests are shown.

  2. Class E power amplifiers for wireless communications

    NASA Astrophysics Data System (ADS)

    Sowlati Hashjani, Tirdad

    In this thesis, the use of Class E power amplifiers for digital wireless communication applications is presented for the first time. A linear transmitter design using Class E amplifier is proposed for the North American Digital Cellular Standard. In this architecture, a phase correcting feedback loop is used to cancel the AM-PM distortion in Class E power amplifier. Several low voltage Class E power amplifiers, and the phase correcting feedback loop are designed and implemented in a commercially available 0.8 mum GaAs MESFET process. A fully integrated Class E power module operating at 835 MHz is presented. The power module consists of a Class F driver stage and a Class E power amplifier, and delivers 250 mW to the standard 50 Omega load with a power added efficiency of 51%. The design and implementation of a hybrid Class E power module operating at 835 MHz is also discussed. In this design, the output matching network is implemented on an alumina substrate, and has a lower power dissipation than its GaAs counterpart. The power module delivers 443 mW to the 50 Omega load with a power added efficiency of 67%. A 1.8 GHz fully integrated Class E power module is also presented. In this case, the power module delivers 200 mW of power to the 50 Omega load with a power added efficiency of 57%. The design and implementation of the phase correcting feedback loop, which consists of a limiting amplifier, a phase detector and two phase shifters, are discussed. The phase correcting feedback loop is used to linearize the 835 MHz Class E hybrid power module. With a loop gain of 20, the maximum phase distortion in the power module was reduced from 30sp° to 4sp° and the total power added efficiency was 65%.

  3. Transverse intensity transformation by laser amplifiers

    NASA Astrophysics Data System (ADS)

    Litvin, Igor A.; King, Gary; Collett, Oliver J. P.; Strauss, Hencharl J.

    2015-03-01

    Lasers beams with a specific intensity profile such as super-Gaussian, Airy or Dougnut-like are desirable in many applications such as laser materials processing, medicine and communications. We propose a new technique for laser beam shaping by amplifying a beam in an end-pumped bulk amplifier that is pumped with a beam that has a modified intensity profile. Advantages of this method are that it is relatively easy to implement, has the ability to reshape multimode beams and is naturally suited to high power/energy beams. Both three and four level gain materials can be used as amplifier media. However, a big advantage of using three level materials is their ability to attenuate of the seed beam, which enhances the contrast of the shaping. We first developed a numerical method to obtain the required pump intensity for an arbitrary beam transformation. This method was subsequently experimentally verified using a three level system. The output of a 2.07 μm seed laser was amplified in a Ho:YLF bulk amplifier which was being pumped by a 1.89 μm Tm:YLF laser which had roughly a TEM10 Hermit Gaussian intensity profile. The seed beam was amplified from 0.3 W to 0.55 W at the full pump power of 35 W. More importantly, the beam profile in one transverse direction was significantly shaped from Gaussian to roughly flat-top, as the model predicted. The concept has therefore been shown to be viable and can be used to optimise the beam profile for a wide range of applications.

  4. Master-Oscillator/Power-Amplifier Laser System

    NASA Technical Reports Server (NTRS)

    Yu, Anthony W.; Krainak, Michael A.; Unger, Glenn L.

    1994-01-01

    Master-oscillator/power-amplifier (MOPA) laser system operates in continuous-wave mode or in amplitude-modulation (e.g., pulse) mode by modulation of oscillator current. Power amplifier is laser-diode-pumped neodymium:yttrium lithium fluoride (Nd:YLF) laser; oscillator is laser diode. Offers relatively high efficiency and power. Because drive current to oscillator modulated, external electro-optical modulator not needed. Potential uses include free-space optical communications, coded laser ranging, and generation of high-power, mode-locked pulses.

  5. Beyond nonlinear saturation of backward Raman amplifiers

    NASA Astrophysics Data System (ADS)

    Barth, Ido; Toroker, Zeev; Balakin, Alexey A.; Fisch, Nathaniel J.

    2016-06-01

    Backward Raman amplification is limited by relativistic nonlinear dephasing resulting in saturation of the leading spike of the amplified pulse. Pump detuning is employed to mitigate the relativistic phase mismatch and to overcome the associated saturation. The amplified pulse can then be reshaped into a monospike pulse with little precursory power ahead of it, with the maximum intensity increasing by a factor of two. This detuning can be employed advantageously both in regimes where the group velocity dispersion is unimportant and where the dispersion is important but small.

  6. Beyond nonlinear saturation of backward Raman amplifiers.

    PubMed

    Barth, Ido; Toroker, Zeev; Balakin, Alexey A; Fisch, Nathaniel J

    2016-06-01

    Backward Raman amplification is limited by relativistic nonlinear dephasing resulting in saturation of the leading spike of the amplified pulse. Pump detuning is employed to mitigate the relativistic phase mismatch and to overcome the associated saturation. The amplified pulse can then be reshaped into a monospike pulse with little precursory power ahead of it, with the maximum intensity increasing by a factor of two. This detuning can be employed advantageously both in regimes where the group velocity dispersion is unimportant and where the dispersion is important but small. PMID:27415380

  7. Cryogenic transimpedance amplifier for micromechanical capacitive sensors.

    PubMed

    Antonio, D; Pastoriza, H; Julián, P; Mandolesi, P

    2008-08-01

    We developed a cryogenic transimpedance amplifier that works at a broad range of temperatures, from room temperature down to 4 K. The device was realized with a standard complementary metal oxide semiconductor 1.5 mum process. Measurements of current-voltage characteristics, open-loop gain, input referred noise current, and power consumption are presented as a function of temperature. The transimpedance amplifier has been successfully applied to sense the motion of a polysilicon micromechanical oscillator at low temperatures. The whole device is intended to serve as a magnetometer for microscopic superconducting samples.

  8. Beyond nonlinear saturation of backward Raman amplifiers

    DOE PAGES

    Barth, Ido; Toroker, Zeev; Balakin, Alexey A.; Fisch, Nathaniel J.

    2016-06-27

    Backward Raman amplification is limited by relativistic nonlinear dephasing resulting in saturation of the leading spike of the amplified pulse. We employed pump detuning in order to mitigate the relativistic phase mismatch and to overcome the associated saturation. In an amplified pulse can then be reshaped into a monospike pulse with little precursory power ahead of it, with the maximum intensity increasing by a factor of two. Finally, this detuning can be employed advantageously both in regimes where the group velocity dispersion is unimportant and where the dispersion is important but small.

  9. Advanced Organic Permeable-Base Transistor with Superior Performance.

    PubMed

    Klinger, Markus P; Fischer, Axel; Kaschura, Felix; Scholz, Reinhard; Lüssem, Björn; Kheradmand-Boroujeni, Bahman; Ellinger, Frank; Kasemann, Daniel; Leo, Karl

    2015-12-16

    An optimized vertical organic permeable-base transistor (OPBT) competing with the best organic field-effect transistors in performance, while employing low-cost fabrication techniques, is presented. The OPBT stands out by its excellent power efficiency at the highest frequencies.

  10. Transistor bonding pad configuration for uniform injection and low inductance

    NASA Technical Reports Server (NTRS)

    Jacobson, D. S.

    1970-01-01

    Modification of process for fabricating transistors, which comprises a metallization-pattern design for emitter and base areas together with a double bonding configuration for each emitter and base-bonding lead, improves uniformity of carrier injection in transistors and of reducing lead inductances at base-emitter terminals.

  11. Low-Inductance Wiring For Parallel Switching Transistors

    NASA Technical Reports Server (NTRS)

    Veatch, M. S.; Landis, D. M.

    1990-01-01

    Simple configuration for wiring of multiple parallel-connected switching transistors minimizes stray wiring inductance while providing for use of balancing transformers, which equalize currents in transistors. Currents balanced on twisted pairs of wires. Because twisted pairs carry both "hot-side" and return currents, this configuration has relatively low inductance.

  12. Method for double-sided processing of thin film transistors

    DOEpatents

    Yuan, Hao-Chih; Wang, Guogong; Eriksson, Mark A.; Evans, Paul G.; Lagally, Max G.; Ma, Zhenqiang

    2008-04-08

    This invention provides methods for fabricating thin film electronic devices with both front- and backside processing capabilities. Using these methods, high temperature processing steps may be carried out during both frontside and backside processing. The methods are well-suited for fabricating back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.

  13. Doped organic transistors operating in the inversion and depletion regime

    PubMed Central

    Lüssem, Björn; Tietze, Max L.; Kleemann, Hans; Hoßbach, Christoph; Bartha, Johann W.; Zakhidov, Alexander; Leo, Karl

    2013-01-01

    The inversion field-effect transistor is the basic device of modern microelectronics and is nowadays used more than a billion times on every state-of-the-art computer chip. In the future, this rigid technology will be complemented by flexible electronics produced at extremely low cost. Organic field-effect transistors have the potential to be the basic device for flexible electronics, but still need much improvement. In particular, despite more than 20 years of research, organic inversion mode transistors have not been reported so far. Here we discuss the first realization of organic inversion transistors and the optimization of organic depletion transistors by our organic doping technology. We show that the transistor parameters—in particular, the threshold voltage and the ON/OFF ratio—can be controlled by the doping concentration and the thickness of the transistor channel. Injection of minority carriers into the doped transistor channel is achieved by doped contacts, which allows forming an inversion layer. PMID:24225722

  14. Self-amplified CMOS image sensor using a current-mode readout circuit

    NASA Astrophysics Data System (ADS)

    Santos, Patrick M.; de Lima Monteiro, Davies W.; Pittet, Patrick

    2014-05-01

    The feature size of the CMOS processes decreased during the past few years and problems such as reduced dynamic range have become more significant in voltage-mode pixels, even though the integration of more functionality inside the pixel has become easier. This work makes a contribution on both sides: the possibility of a high signal excursion range using current-mode circuits together with functionality addition by making signal amplification inside the pixel. The classic 3T pixel architecture was rebuild with small modifications to integrate a transconductance amplifier providing a current as an output. The matrix with these new pixels will operate as a whole large transistor outsourcing an amplified current that will be used for signal processing. This current is controlled by the intensity of the light received by the matrix, modulated pixel by pixel. The output current can be controlled by the biasing circuits to achieve a very large range of output signal levels. It can also be controlled with the matrix size and this permits a very high degree of freedom on the signal level, observing the current densities inside the integrated circuit. In addition, the matrix can operate at very small integration times. Its applications would be those in which fast imaging processing, high signal amplification are required and low resolution is not a major problem, such as UV image sensors. Simulation results will be presented to support: operation, control, design, signal excursion levels and linearity for a matrix of pixels that was conceived using this new concept of sensor.

  15. Long-Term Reliability of High Speed SiGe/Si Heterojunction Bipolar Transistors

    NASA Technical Reports Server (NTRS)

    Ponchak, George E. (Technical Monitor); Bhattacharya, Pallab

    2003-01-01

    Accelerated lifetime tests were performed on double-mesa structure Si/Si0.7Ge0.3/Si npn heterojunction bipolar transistors, grown by molecular beam epitaxy, in the temperature range of 175C-275C. Both single- and multiple finger transistors were tested. The single-finger transistors (with 5x20 micron sq m emitter area) have DC current gains approximately 40-50 and f(sub T) and f(sub MAX) of up to 22 GHz and 25 GHz, respectively. The multiple finger transistors (1.4 micron finger width, 9 emitter fingers with total emitter area of 403 micron sq m) have similar DC current gain but f(sub T) of 50 GHz. It is found that a gradual degradation in these devices is caused by the recombination enhanced impurity diffusion (REID) of boron atoms from the p-type base region and the associated formation of parasitic energy barriers to electron transport from the emitter to collector layers. This REID has been quantitatively modeled and explained, to the first order of approximation, and the agreement with the measured data is good. The mean time to failure (MTTF) of the devices at room temperature is estimated from the extrapolation of the Arrhenius plots of device lifetime versus reciprocal temperature. The results of the reliability tests offer valuable feedback for SiGe heterostructure design in order to improve the long-term reliability of the devices and circuits made with them. Hot electron induced degradation of the base-emitter junction was also observed during the accelerated lifetime testing. In order to improve the HBT reliability endangered by the hot electrons, deuterium sintered techniques have been proposed. The preliminary results from this study show that a deuterium-sintered HBT is, indeed, more resistant to hot-electron induced base-emitter junction degradation. SiGe/Si based amplifier circuits were also subjected to lifetime testing and we extrapolate MTTF is approximately 1.1_10(exp 6) hours at 125iC junction temperature from the circuit lifetime data.

  16. Measuring the energy of amplified spontaneous emission (ASE) in a short pulse laser amplifier

    NASA Astrophysics Data System (ADS)

    Iliev, Marin; Adams, Daniel; Greco, Michael; Meier, Amanda; Squier, Jeff; Durfee, Charles

    2010-10-01

    In high-gain pulsed laser amplifiers, amplified spontaneous emission (ASE) tends to limit the gain in single stage fiber amplifiers. Even if ASE is not strong enough to deplete the gain of the amplifier, it still contributes strongly to a low-intensity background output in the amplified signal. The intensity contrast between the amplified short pulse and this background ASE pedestal can be measured with third-order autocorrelation, but this method cannot be used to completely specify the ASE's energy, which is distributed over many nanoseconds. We have developed a novel method that allows us to determine the energy and the spectrum of the ASE. We use a cross polarized wave (XPW) generating crystal such as BaF2 to ``clean up'' the ASE from the short pulse(SP). The input pulse (SP and ASE) and the cross-polarized signal are passed through a birefringent crystal such as sapphire. The relative group velocity difference along each crystal axis results in a delay between both channels. After passing through a polarizer, an interferogram is obtained in a spectrometer. This interferogram results from interference of the XPW pulse with the short-pulse content of the amplifier output, with a background of the ASE spectrum. Fourier analysis yields both the ASE energy and its spectrum.

  17. Progress Towards High-Sensitivity Arrays of Detectors of Sub-mm Radiation Using Superconducting Tunnel Junctions with Integrated Radio Frequency Single-Electron Transistors

    NASA Technical Reports Server (NTRS)

    Stevenson, T. R.; Hsieh, W.-T.; Li, M. J.; Prober, D. E.; Rhee, K. W.; Schoelkopf, R. J.; Stahle, C. M.; Teufel, J.; Wollack, E. J.

    2004-01-01

    For high resolution imaging and spectroscopy in the FIR and submillimeter, space observatories will demand sensitive, fast, compact, low-power detector arrays with 104 pixels and sensitivity less than 10(exp -20) W/Hz(sup 0.5). Antenna-coupled superconducting tunnel junctions with integrated rf single-electron transistor readout amplifiers have the potential for achieving this high level of sensitivity, and can take advantage of an rf multiplexing technique. The device consists of an antenna to couple radiation into a small superconducting volume and cause quasiparticle excitations, and a single-electron transistor to measure current through junctions contacting the absorber. We describe optimization of device parameters, and results on fabrication techniques for producing devices with high yield for detector arrays. We also present modeling of expected saturation power levels, antenna coupling, and rf multiplexing schemes.

  18. Current gain in sub-10 nm base GaN tunneling hot electron transistors with AlN emitter barrier

    SciTech Connect

    Yang, Zhichao Zhang, Yuewei; Nath, Digbijoy N.; Rajan, Siddharth; Khurgin, Jacob B.

    2015-01-19

    We report on Gallium Nitride-based tunneling hot electron transistor amplifier with common-emitter current gain greater than 1. Small signal current gain up to 5 and dc current gain of 1.3 were attained in common-emitter configuration with collector current density in excess of 50 kA/cm{sup 2}. The use of a combination of 1 nm GaN/3 nm AlN layers as an emitter tunneling barrier was found to improve the energy collimation of the injected electrons. These results represent demonstration of unipolar vertical transistors in the III-nitride system that can potentially lead to higher frequency and power microwave devices.

  19. A spiking neuron circuit based on a carbon nanotube transistor.

    PubMed

    Chen, C-L; Kim, K; Truong, Q; Shen, A; Li, Z; Chen, Y

    2012-07-11

    A spiking neuron circuit based on a carbon nanotube (CNT) transistor is presented in this paper. The spiking neuron circuit has a crossbar architecture in which the transistor gates are connected to its row electrodes and the transistor sources are connected to its column electrodes. An electrochemical cell is incorporated in the gate of the transistor by sandwiching a hydrogen-doped poly(ethylene glycol)methyl ether (PEG) electrolyte between the CNT channel and the top gate electrode. An input spike applied to the gate triggers a dynamic drift of the hydrogen ions in the PEG electrolyte, resulting in a post-synaptic current (PSC) through the CNT channel. Spikes input into the rows trigger PSCs through multiple CNT transistors, and PSCs cumulate in the columns and integrate into a 'soma' circuit to trigger output spikes based on an integrate-and-fire mechanism. The spiking neuron circuit can potentially emulate biological neuron networks and their intelligent functions.

  20. I-V Characteristics of a Ferroelectric Field Effect Transistor

    NASA Technical Reports Server (NTRS)

    MacLeod, Todd C.; Ho, Fat Duen

    1999-01-01

    There are many possible uses for ferroelectric field effect transistors.To understand their application, a fundamental knowledge of their basic characteristics must first be found. In this research, the current and voltage characteristics of a field effect transistor are described. The effective gate capacitance and charge are derived from experimental data on an actual FFET. The general equation for a MOSFET is used to derive the internal characteristics of the transistor: This equation is modified slightly to describe the FFET characteristics. Experimental data derived from a Radiant Technologies FFET is used to calculate the internal transistor characteristics using fundamental MOSFET equations. The drain current was measured under several different gate and drain voltages and with different initial polarizations on the ferroelectric material in the transistor. Two different polarization conditions were used. One with the gate ferroelectric material polarized with a +9.0 volt write pulse and one with a -9.0 volt pulse.

  1. Organic transistors manufactured using inkjet technology with subfemtoliter accuracy

    PubMed Central

    Sekitani, Tsuyoshi; Noguchi, Yoshiaki; Zschieschang, Ute; Klauk, Hagen; Someya, Takao

    2008-01-01

    A major obstacle to the development of organic transistors for large-area sensor, display, and circuit applications is the fundamental compromise between manufacturing efficiency, transistor performance, and power consumption. In the past, improving the manufacturing efficiency through the use of printing techniques has inevitably resulted in significantly lower performance and increased power consumption, while attempts to improve performance or reduce power have led to higher process temperatures and increased manufacturing cost. Here, we lift this fundamental limitation by demonstrating subfemtoliter inkjet printing to define metal contacts with single-micrometer resolution on the surface of high-mobility organic semiconductors to create high-performance p-channel and n-channel transistors and low-power complementary circuits. The transistors employ an ultrathin low-temperature gate dielectric based on a self-assembled monolayer that allows transistors and circuits on rigid and flexible substrates to operate with very low voltages. PMID:18362348

  2. A spiking neuron circuit based on a carbon nanotube transistor

    NASA Astrophysics Data System (ADS)

    Chen, C.-L.; Kim, K.; Truong, Q.; Shen, A.; Li, Z.; Chen, Y.

    2012-07-01

    A spiking neuron circuit based on a carbon nanotube (CNT) transistor is presented in this paper. The spiking neuron circuit has a crossbar architecture in which the transistor gates are connected to its row electrodes and the transistor sources are connected to its column electrodes. An electrochemical cell is incorporated in the gate of the transistor by sandwiching a hydrogen-doped poly(ethylene glycol)methyl ether (PEG) electrolyte between the CNT channel and the top gate electrode. An input spike applied to the gate triggers a dynamic drift of the hydrogen ions in the PEG electrolyte, resulting in a post-synaptic current (PSC) through the CNT channel. Spikes input into the rows trigger PSCs through multiple CNT transistors, and PSCs cumulate in the columns and integrate into a ‘soma’ circuit to trigger output spikes based on an integrate-and-fire mechanism. The spiking neuron circuit can potentially emulate biological neuron networks and their intelligent functions.

  3. A spiking neuron circuit based on a carbon nanotube transistor.

    PubMed

    Chen, C-L; Kim, K; Truong, Q; Shen, A; Li, Z; Chen, Y

    2012-07-11

    A spiking neuron circuit based on a carbon nanotube (CNT) transistor is presented in this paper. The spiking neuron circuit has a crossbar architecture in which the transistor gates are connected to its row electrodes and the transistor sources are connected to its column electrodes. An electrochemical cell is incorporated in the gate of the transistor by sandwiching a hydrogen-doped poly(ethylene glycol)methyl ether (PEG) electrolyte between the CNT channel and the top gate electrode. An input spike applied to the gate triggers a dynamic drift of the hydrogen ions in the PEG electrolyte, resulting in a post-synaptic current (PSC) through the CNT channel. Spikes input into the rows trigger PSCs through multiple CNT transistors, and PSCs cumulate in the columns and integrate into a 'soma' circuit to trigger output spikes based on an integrate-and-fire mechanism. The spiking neuron circuit can potentially emulate biological neuron networks and their intelligent functions. PMID:22710137

  4. Flexible Proton-Gated Oxide Synaptic Transistors on Si Membrane.

    PubMed

    Zhu, Li Qiang; Wan, Chang Jin; Gao, Ping Qi; Liu, Yang Hui; Xiao, Hui; Ye, Ji Chun; Wan, Qing

    2016-08-24

    Ion-conducting materials have received considerable attention for their applications in fuel cells, electrochemical devices, and sensors. Here, flexible indium zinc oxide (InZnO) synaptic transistors with multiple presynaptic inputs gated by proton-conducting phosphorosilicate glass-based electrolyte films are fabricated on ultrathin Si membranes. Transient characteristics of the proton gated InZnO synaptic transistors are investigated, indicating stable proton-gating behaviors. Short-term synaptic plasticities are mimicked on the proposed proton-gated synaptic transistors. Furthermore, synaptic integration regulations are mimicked on the proposed synaptic transistor networks. Spiking logic modulations are realized based on the transition between superlinear and sublinear synaptic integration. The multigates coupled flexible proton-gated oxide synaptic transistors may be interesting for neuroinspired platforms with sophisticated spatiotemporal information processing. PMID:27471861

  5. AMPLIFIED TELEPHONE AS A TEACHING MEDIUM.

    ERIC Educational Resources Information Center

    JOLLY, JOAN; MADDEN, CHARLES F.

    A GRANT TOTALING $58,400 FROM THE FUND FOR THE ADVANCEMENT OF EDUCATION ENABLED STEPHENS COLLEGE TO INITIATE AN EXPERIMENTAL EDUCATIONAL PROGRAM BY WHICH AMPLIFIED TELEPHONE COMMUNICATION BROUGHT HIGH-QUALITY INSTRUCTION TO GROUPS OF SMALL LIBERAL ARTS COLLEGES. A "MASTER TEACHER" ORGANIZED AND PRESENTED THE BASIC MATERIALS OF THE COURSE. PERSONS…

  6. Stereoscopy Amplifies Emotions Elicited by Facial Expressions

    PubMed Central

    Kätsyri, Jari; Häkkinen, Jukka

    2015-01-01

    Mediated facial expressions do not elicit emotions as strongly as real-life facial expressions, possibly due to the low fidelity of pictorial presentations in typical mediation technologies. In the present study, we investigated the extent to which stereoscopy amplifies emotions elicited by images of neutral, angry, and happy facial expressions. The emotional self-reports of positive and negative valence (which were evaluated separately) and arousal of 40 participants were recorded. The magnitude of perceived depth in the stereoscopic images was manipulated by varying the camera base at 15, 40, 65, 90, and 115 mm. The analyses controlled for participants’ gender, gender match, emotional empathy, and trait alexithymia. The results indicated that stereoscopy significantly amplified the negative valence and arousal elicited by angry expressions at the most natural (65 mm) camera base, whereas stereoscopy amplified the positive valence elicited by happy expressions in both the narrowed and most natural (15–65 mm) base conditions. Overall, the results indicate that stereoscopy amplifies the emotions elicited by mediated emotional facial expressions when the depth geometry is close to natural. The findings highlight the sensitivity of the visual system to depth and its effect on emotions. PMID:27551358

  7. Stereoscopy Amplifies Emotions Elicited by Facial Expressions.

    PubMed

    Hakala, Jussi; Kätsyri, Jari; Häkkinen, Jukka

    2015-12-01

    Mediated facial expressions do not elicit emotions as strongly as real-life facial expressions, possibly due to the low fidelity of pictorial presentations in typical mediation technologies. In the present study, we investigated the extent to which stereoscopy amplifies emotions elicited by images of neutral, angry, and happy facial expressions. The emotional self-reports of positive and negative valence (which were evaluated separately) and arousal of 40 participants were recorded. The magnitude of perceived depth in the stereoscopic images was manipulated by varying the camera base at 15, 40, 65, 90, and 115 mm. The analyses controlled for participants' gender, gender match, emotional empathy, and trait alexithymia. The results indicated that stereoscopy significantly amplified the negative valence and arousal elicited by angry expressions at the most natural (65 mm) camera base, whereas stereoscopy amplified the positive valence elicited by happy expressions in both the narrowed and most natural (15-65 mm) base conditions. Overall, the results indicate that stereoscopy amplifies the emotions elicited by mediated emotional facial expressions when the depth geometry is close to natural. The findings highlight the sensitivity of the visual system to depth and its effect on emotions. PMID:27551358

  8. NON-BLOCKING STABILIZED FEED BACK AMPLIFIER

    DOEpatents

    Fairstein, E.

    1960-03-01

    A plural stuge nonblocking degenerative feed-back amplifier was designed particularly suitable for counting circuits because of the stability and linearity in operation, characterized by the fact that the inltial stage employs a cathode coupled input circuit fed from a cathode follower and the final stage has a tline constant greater than those of the other stages.

  9. Stereoscopy Amplifies Emotions Elicited by Facial Expressions.

    PubMed

    Hakala, Jussi; Kätsyri, Jari; Häkkinen, Jukka

    2015-12-01

    Mediated facial expressions do not elicit emotions as strongly as real-life facial expressions, possibly due to the low fidelity of pictorial presentations in typical mediation technologies. In the present study, we investigated the extent to which stereoscopy amplifies emotions elicited by images of neutral, angry, and happy facial expressions. The emotional self-reports of positive and negative valence (which were evaluated separately) and arousal of 40 participants were recorded. The magnitude of perceived depth in the stereoscopic images was manipulated by varying the camera base at 15, 40, 65, 90, and 115 mm. The analyses controlled for participants' gender, gender match, emotional empathy, and trait alexithymia. The results indicated that stereoscopy significantly amplified the negative valence and arousal elicited by angry expressions at the most natural (65 mm) camera base, whereas stereoscopy amplified the positive valence elicited by happy expressions in both the narrowed and most natural (15-65 mm) base conditions. Overall, the results indicate that stereoscopy amplifies the emotions elicited by mediated emotional facial expressions when the depth geometry is close to natural. The findings highlight the sensitivity of the visual system to depth and its effect on emotions.

  10. LOW-LEVEL DIRECT CURRENT AMPLIFIER

    DOEpatents

    Kerns, Q.A.

    1959-05-01

    A d-c amplifier is described. Modulation is provided between a d-c signal and an alternating current to give an output signal proportional to the d- c signal. The circuit has high sensitivity and accuracy. (T.R.H.)

  11. Reflected-wave maser. [low noise amplifier

    NASA Technical Reports Server (NTRS)

    Clauss, R. C. (Inventor)

    1976-01-01

    A number of traveling-wave, slow-wave maser structures, containing active maser material but absent the typical ferrite isolators, are immersed in a nonuniform magnetic field. The microwave signal to be amplified is inserted at a circulator which directs the signal to a slow-wave structure. The signal travels through the slow-wave structure, being amplified according to the distance traveled. The end of the slow-wave structure farthest from the circulator is arranged to be a point of maximum reflection of the signal traveling through the slow-wave structure. As a consequence, the signal to be amplified traverses the slow-wave structure again, in the opposite direction (towards the circulator) experiencing amplification equivalent to that achieved by a conventional traveling-wave maser having twice the length. The circulator directs the amplified signal to following like stages of amplification. Isolators are used in between stages to prevent signals from traveling in the wrong direction, between the stages. Reduced signal loss is experienced at each stage. The high gain produced by each slow-wave structure is reduced to a moderate value by use of a nonuniform magnetic field which also broadens the line width of the maser material. The resulting bandwidth can be exceptionally wide. Cascaded stages provide high gain, exceptionally wide bandwith and very low noise temperature.

  12. Simulations of the LANL regenerative amplifier FEL

    SciTech Connect

    Kesselring, M.; Colson, W.B.; Wong, R.K.; Sheffield, R.L.

    1997-08-01

    The LANL regenerative amplifier FEL is designed to produce an average output power of 1 kW. Simulations study the transverse effects due to guiding by the intense electron beam and feedback. These simulations coupled with experimental measurements can be used to improve future high-power FEL designs.

  13. Analysis of a multistable semiconductor light amplifier

    SciTech Connect

    Otsuka, K.; Iwamura, H.

    1983-07-01

    A multistable operation in semiconductor laser amplifiers, based upon the carrier density dependence of the active region refractive index, is proposed. Simple analytical expressions describing the optical multistability are given, using the so-called antiguidance factor, which is the ratio of the decrease in the real refractive index to the increase in the imaginary refractive index.

  14. Kondo Effect in a Single Electron Transistor

    NASA Astrophysics Data System (ADS)

    Goldhaber-Gordon, David

    1998-03-01

    When a field-effect transistor is made very small, and electrons in the channel are separated from those in the leads by tunnel junctions, the transistor turns on and off every time an extra electron is added to the channel. The droplet of electrons confined in the channel of such a single-electron transistor (SET) interacts with electrons in the leads. This is in close analogy to an impurity atom interacting with the delocalized electrons in a metal, the traditional system for studying the Kondo effect.(Y. Meir, N.S. Wingreen, and P.A. Lee. PRL) 70, 2601 (1993) I will discuss measurements on a new generation of SETs that display all the aspects of the Kondo effect:(D. Goldhaber-Gordon, Hadas Shtrikman, D. Mahalu, D. Abusch-Magder, U. Meirav, and M.A. Kastner. To be published in Nature). a spin singlet forms between a localized electron in the channel and delocalized electrons in the leads, causing an enhancement of the zero-bias conductance, when the number of electrons on the artificial atom is odd but not when it is even. The system can be studied out of equilibrium by applying a voltage between the two leads, an impossible procedure in bulk Kondo systems. The spin singlet is altered by applying such a voltage or a magnetic field or by increasing the temperature, all in ways that agree with predictions. In addition, the tunability of an SET allows study of the system over a range of parameters not easily accessible to previous calculations or experiments.

  15. Narrow-linewidth master-oscillator power amplifier based on a semiconductor tapered amplifier.

    PubMed

    Wilson, A C; Sharpe, J C; McKenzie, C R; Manson, P J; Warrington, D M

    1998-07-20

    The output of a grating-stabilized external-cavity diode laser was injected into a semiconductor tapered amplifier in a master-oscillator power amplifier configuration, producing as much as 500 mW of power with narrow linewidth. The additional linewidth that is due to the tapered amplifier is much smaller than the typical linewidth of grating-stabilized laser diodes. To demonstrate the usefulness of the narrow linewidth and high output power, we used the system to perform Doppler-free two-photon spectroscopy with rubidium. PMID:18285950

  16. Dose Rate Effects in Linear Bipolar Transistors

    NASA Technical Reports Server (NTRS)

    Johnston, Allan; Swimm, Randall; Harris, R. D.; Thorbourn, Dennis

    2011-01-01

    Dose rate effects are examined in linear bipolar transistors at high and low dose rates. At high dose rates, approximately 50% of the damage anneals at room temperature, even though these devices exhibit enhanced damage at low dose rate. The unexpected recovery of a significant fraction of the damage after tests at high dose rate requires changes in existing test standards. Tests at low temperature with a one-second radiation pulse width show that damage continues to increase for more than 3000 seconds afterward, consistent with predictions of the CTRW model for oxides with a thickness of 700 nm.

  17. Hafnium transistor process design for neural interfacing.

    PubMed

    Parent, David W; Basham, Eric J

    2009-01-01

    A design methodology is presented that uses 1-D process simulations of Metal Insulator Semiconductor (MIS) structures to design the threshold voltage of hafnium oxide based transistors used for neural recording. The methodology is comprised of 1-D analytical equations for threshold voltage specification, and doping profiles, and 1-D MIS Technical Computer Aided Design (TCAD) to design a process to implement a specific threshold voltage, which minimized simulation time. The process was then verified with a 2-D process/electrical TCAD simulation. Hafnium oxide films (HfO) were grown and characterized for dielectric constant and fixed oxide charge for various annealing temperatures, two important design variables in threshold voltage design.

  18. Gate engineered performance of single molecular transistor

    NASA Astrophysics Data System (ADS)

    Ray, S. J.

    2016-05-01

    The operation, performance and electrostatics of multigated Single Molecular Transistor (SMT) devices are investigated using first-principles based density functional theory calculations for planar (pentacene) and non-planar (sucrose) molecules as islands. It has been found that the incorporation of larger numbers of gates allows enhanced electrostatic control in the SMT operation which has been quantified from the energy calculations and estimation of the gate capacitances. The effect of multiple gates is more dominant for a non-planar molecule than a planar molecule within an SMT which indicates the usefulness of such multi-gate architectures for future nanoelectronic devices.

  19. Relationship Between Latchup And Transistor Current Gain

    NASA Technical Reports Server (NTRS)

    Edmonds, Larry D.

    1989-01-01

    Theoretical study takes new look at current-vs.-voltage behavior of silicon controlled rectifiers (SCR's), four-layer complementary metal oxide/semiconductor (CMOS) devices, and similar devices susceptible to latchup. For purposes of analysis, "latchup" denotes transition of such device from lower-current-conducting steady state to distinct higher-current-conducting steady state. Focuses upon conventional two-couple-transistor model of one-dimensional SCR. Although model gives oversimplified view of latchup in CMOS circuits, useful for qualitative predictions of electrical characteristics.

  20. Hysteresis modeling in graphene field effect transistors

    SciTech Connect

    Winters, M.; Rorsman, N.; Sveinbjörnsson, E. Ö.

    2015-02-21

    Graphene field effect transistors with an Al{sub 2}O{sub 3} gate dielectric are fabricated on H-intercalated bilayer graphene grown on semi-insulating 4H-SiC by chemical vapour deposition. DC measurements of the gate voltage v{sub g} versus the drain current i{sub d} reveal a severe hysteresis of clockwise orientation. A capacitive model is used to derive the relationship between the applied gate voltage and the Fermi energy. The electron transport equations are then used to calculate the drain current for a given applied gate voltage. The hysteresis in measured data is then modeled via a modified Preisach kernel.

  1. Perpendicular transport in superlattice bipolar transistors (SBT)

    NASA Astrophysics Data System (ADS)

    Sibille, A.; Palmier, J. F.; Minot, C.; Harmand, J. C.; Dubon-Chevallier, C.

    Diffusion-limited electron transport in superlattices is studied by gain measurements on heterojunction bipolar transistors with a {GaAs}/{GaAlAs} superlattice base. In the case of thin barriers, Bloch conduction is observed, while hopping between localized levels prevails for large barriers. A transition occurs between these two regimes, localization being achieved when the energy broadening induced by the electron-phonon coupling added to the disorder due to imperfect growth is of the order of the miniband width. This interpretation is supported by temperature dependence measurements of the perpendicular mobilities in relation with theoretical calculations of these mobilities.

  2. Radiation-hard static induction transistor

    SciTech Connect

    Hanes, M.H.; Bartko, J.; Hwang, J.M.; Rai-Choudhury, P.; Leslie, S.G.

    1988-12-01

    The static induction transistor (SIT) has been proposed as a preferred power switching device for applications in military and space environments because of its potential for radiation hardness, high-frequency operation, and the incorporation of on-chip smart power sensor and logic functions. Design, fabrication, and characteristics of a 350 V, 100 A buried gate SIT are described. The potential radiation hardness of this class of devices was evaluated by measurement of SIT characteristics after irradiation with 100 Mrad electrons (2 MeV), and up to 10%16% fission neutrons/cm/sup 2/. High-temperature operation and the possibility of radiation damage self-annealing are discussed.

  3. Transistor screening evaluation SJ6708H

    NASA Technical Reports Server (NTRS)

    Barton, J. L.

    1978-01-01

    A manufacturer was contracted to screen 125 transistors capable of withstanding the high level inductive voltages obtained when switching inductive loads. Planned differences included a change in die bonding to comply with NASA's desire for hard solder die attachment which further necessitated a change in package to conform to the required die mounting system. Evaluation of the electrical performance and recommended changes were made during the preliminary build phase of the program. The following sections are outlined: (1) narrative outline; (2) customer data summary and X-ray reports; (3) device specification; (4) failure analysis reports; (5) test facilities list; and (6) test measurement data.

  4. Printed shadow masks for organic transistors

    NASA Astrophysics Data System (ADS)

    Noguchi, Yoshiaki; Sekitani, Tsuyoshi; Someya, Takao

    2007-09-01

    We have manufactured organic field-effect transistors by using shadow masks that are patterned by a screen printing system. The 50-nm-thick pentacene layer is sublimed as a channel in the vacuum system through the shadow mask on the base film with a multilayer patterned by ink-jet. After the deposition of the pentacene layer, the shadow mask is peeled off from the base film without any mechanical damages to the lower structures. The mobility in the saturation regime is 0.4cm2/Vs and the on-off ratio exceeds 105.

  5. Multi-pass amplifier architecture for high power laser systems

    DOEpatents

    Manes, Kenneth R; Spaeth, Mary L; Erlandson, Alvin C

    2014-04-01

    A main amplifier system includes a first reflector operable to receive input light through a first aperture and direct the input light along an optical path. The input light is characterized by a first polarization. The main amplifier system also includes a first polarizer operable to reflect light characterized by the first polarization state. The main amplifier system further includes a first and second set of amplifier modules. Each of the first and second set of amplifier modules includes an entrance window, a quarter wave plate, a plurality of amplifier slablets arrayed substantially parallel to each other, and an exit window. The main amplifier system additionally includes a set of mirrors operable to reflect light exiting the first set of amplifier modules to enter the second set of amplifier modules and a second polarizer operable to reflect light characterized by a second polarization state.

  6. Amplifier spurious input current components in electrode-electrolyte interface impedance measurements

    PubMed Central

    Felice, Carmelo J; Madrid, Rossana E; Valentinuzzi, Max E

    2005-01-01

    Background In Impedance Microbiology, the time during which the measuring equipment is connected to the bipolar cells is rather long, usually between 6 to 24 hrs for microorganisms with duplication times in the order of less than one hour and concentrations ranging from 101 to 107 [CFU/ml]. Under these conditions, the electrode-electrolyte interface impedance may show a slow drift of about 2%/hr. By and large, growth curves superimposed on such drift do not stabilize, are less reproducible, and keep on distorting all over the measurement of the temporal reactive or resistive records due to interface changes, in turn originated in bacterial activity. This problem has been found when growth curves were obtained by means of impedance analyzers or with impedance bridges using different types of operational amplifiers. Methods Suspecting that the input circuitry was the culprit of the deleterious effect, we used for that matter (a) ultra-low bias current amplifiers, (b) isolating relays for the selection of cells, and (c) a shorter connection time, so that the relays were maintained opened after the readings, to bring down such spurious drift to a negligible value. Bacterial growth curves were obtained in order to test their quality. Results It was demonstrated that the drift decreases ten fold when the circuit remained connected to the cell for a short time between measurements, so that the distortion became truly negligible. Improvement due to better-input amplifiers was not as good as by reducing the connection time. Moreover, temperature effects were insignificant with a regulation of ± 0.2 [°C]. Frequency did not influence either. Conclusion The drift originated either at the dc input bias offset current (Ios) of the integrated circuits, or in discrete transistors connected directly to the electrodes immersed in the cells, depending on the particular circuit arrangement. Reduction of the connection time was the best countermeasure. PMID:15796776

  7. Graphene as tunable contact for high performance thin film transistor

    NASA Astrophysics Data System (ADS)

    Liu, Yuan

    Graphene has been one of the most extensively studied materials due to its unique band structure, the linear dispersion at the K point. It gives rise to novel phenomena, such as the anomalous quantum Hall effect, and has opened up a new category of "Fermi-Dirac" physics. Graphene has also attracted enormous attention for future electronics because of its exceptional high carrier mobility, high carrier saturation velocity, and large critical current density. However, graphene has zero intrinsic band gap, thus can not be used as the active channel material for logic transistors with sufficient on/off current ratio. Previous approaches to address this challenge include the induction of a transport gap in graphene nanostructures or bilayer graphene. However, these approaches have proved successful in improving the on-- off ratio of the resulting devices, but often at a severe sacrifice of the deliverable current density. Alternatively, with a finite density of states, tunable work-function and optical transparency, graphene can function as a unique tunable contact material to create a new structure of electronic devices. In this thesis, I will present my effort toward on-off ratio of graphene based vertical thin film transistor. I will include the work form four of my first author publication. I will first present my research studies on the a dramatic enhancement of the overall quantum efficiency and spectral selectivity of graphene photodetector, by coupling with plasmonic nanostructures. It is observed that metallic plasmonic nanostructures can be integrated with graphene photodetectors to greatly enhance the photocurrent and external quantum efficiency by up to 1,500%. Plasmonic nanostructures of variable resonance frequencies selectively amplify the photoresponse of graphene to light of different wavelengths, enabling highly specific detection of multicolours. Then I will show a new design of highly flexible vertical TFTs (VTFTs) with superior electrical

  8. Graphene as tunable contact for high performance thin film transistor

    NASA Astrophysics Data System (ADS)

    Liu, Yuan

    Graphene has been one of the most extensively studied materials due to its unique band structure, the linear dispersion at the K point. It gives rise to novel phenomena, such as the anomalous quantum Hall effect, and has opened up a new category of "Fermi-Dirac" physics. Graphene has also attracted enormous attention for future electronics because of its exceptional high carrier mobility, high carrier saturation velocity, and large critical current density. However, graphene has zero intrinsic band gap, thus can not be used as the active channel material for logic transistors with sufficient on/off current ratio. Previous approaches to address this challenge include the induction of a transport gap in graphene nanostructures or bilayer graphene. However, these approaches have proved successful in improving the on-- off ratio of the resulting devices, but often at a severe sacrifice of the deliverable current density. Alternatively, with a finite density of states, tunable work-function and optical transparency, graphene can function as a unique tunable contact material to create a new structure of electronic devices. In this thesis, I will present my effort toward on-off ratio of graphene based vertical thin film transistor. I will include the work form four of my first author publication. I will first present my research studies on the a dramatic enhancement of the overall quantum efficiency and spectral selectivity of graphene photodetector, by coupling with plasmonic nanostructures. It is observed that metallic plasmonic nanostructures can be integrated with graphene photodetectors to greatly enhance the photocurrent and external quantum efficiency by up to 1,500%. Plasmonic nanostructures of variable resonance frequencies selectively amplify the photoresponse of graphene to light of different wavelengths, enabling highly specific detection of multicolours. Then I will show a new design of highly flexible vertical TFTs (VTFTs) with superior electrical

  9. Hybrid transistor manipulation controlled by light within a PANDA microring resonator.

    PubMed

    Chantanetra, Soontorn; Teeka, Chat; Mitatha, Somsak; Jomtarak, Rangsan; Yupapin, Preecha P

    2012-06-01

    In this paper, the novel type of transistor known as a hybrid transistor is proposed, in which all types of transistors can be formed by using a microring resonator called a PANDA microring resonator. In principle, such a transistor can be used to form for various transistor types by using the atom/molecule trapping tools, which is named by an optical tweezer, where in application all type of transistors, especially, molecule and photon transistors can be performed by using the trapping tools, which will be described in details.

  10. Low phase noise oscillator using two parallel connected amplifiers

    NASA Technical Reports Server (NTRS)

    Kleinberg, Leonard L.

    1987-01-01

    A high frequency oscillator is provided by connecting two amplifier circuits in parallel where each amplifier circuit provides the other amplifier circuit with the conditions necessary for oscillation. The inherent noise present in both amplifier circuits causes the quiescent current, and in turn, the generated frequency, to change. The changes in quiescent current cause the transconductance and the load impedance of each amplifier circuit to vary, and this in turn results in opposing changes in the input susceptance of each amplifier circuit. Because the changes in input susceptance oppose each other, the changes in quiescent current also oppose each other. The net result is that frequency stability is enhanced.

  11. Signal and noise analysis of a-Si:H radiation detector-amplifier system

    SciTech Connect

    Cho, Gyuseong

    1992-03-01

    Hydrogenated amorphous silicon (a-Si:H) has potential advantages in making radiation detectors for many applications because of its deposition capability on a large-area substrate and its high radiation resistance. Position-sensitive radiation detectors can be made out of a 1d strip or a 2-d pixel array of a Si:H pin diodes. In addition, signal processing electronics can be made by thin-film transistors on the same substrate. The calculated radiation signal, based on a simple charge collection model agreed well with results from various wave length light sources and 1 MeV beta particles on sample diodes. The total noise of the detection system was analyzed into (a) shot noise and (b) 1/f noise from a detector diode, and (c) thermal noise and (d) 1/f noise from the frontend TFT of a charge-sensitive preamplifier. the effective noise charge calculated by convoluting these noise power spectra with the transfer function of a CR-RC shaping amplifier showed a good agreement with the direct measurements of noise charge. The derived equations of signal and noise charge can be used to design an a-Si:H pixel detector amplifier system optimally. Signals from a pixel can be readout using switching TFTs, or diodes. Prototype tests of a double-diode readout scheme showed that the storage time and the readout time are limited by the resistances of the reverse-biased pixel diode and the forward biased switching diodes respectively. A prototype charge-sensitive amplifier was made using poly-Si TFTs to test the feasibility of making pixel-level amplifiers which would be required in small-signal detection. The measured overall gain-bandwidth product was {approximately}400 MHz and the noise charge {approximately}1000 electrons at a 1 {mu}sec shaping time. When the amplifier is connected to a pixel detector of capacitance 0.2 pF, it would give a charge-to-voltage gain of {approximately}0.02 mV/electron with a pulse rise time less than 100 nsec and a dynamic range of 48 dB.

  12. Intrinsic delay of permeable base transistor

    SciTech Connect

    Chen, Wenchao; Guo, Jing; So, Franky

    2014-07-28

    Permeable base transistors (PBTs) fabricated by vacuum deposition or solution process have the advantages of easy fabrication and low power operation and are a promising device structure for flexible electronics. Intrinsic delay of PBT, which characterizes the speed of the transistor, is investigated by solving the three-dimensional Poisson equation and drift-diffusion equation self-consistently using finite element method. Decreasing the emitter thickness lowers the intrinsic delay by improving on-current, and a thinner base is also preferred for low intrinsic delay because of fewer carriers in the base region at off-state. The intrinsic delay exponentially decreases as the emitter contact Schottky barrier height decreases, and it linearly depends on the carrier mobility. With an optimized emitter contact barrier height and device geometry, a sub-nano-second intrinsic delay can be achieved with a carrier mobility of ∼10 cm{sup 2}/V/s obtainable in solution processed indium gallium zinc oxide, which indicates the potential of solution processed PBTs for GHz operations.

  13. The cavity-embedded-cooper pair transistor

    NASA Astrophysics Data System (ADS)

    Chen, Fei

    Nearly eight decades after Erwin Schrodinger proposed his famous cat paradox, the boundary between classical and quantum physics is becoming accessible to experimental study in condensed matter systems, in which macroscopic and microscopic degrees of freedom interact with each other. The cavity-embedded-Cooper pair transistor (cCPT) is an ideal candidate for such a study in that it is not only strongly and intrinsically nonlinear but also fully quantum mechanical. A novel technique, based on the circuit quantum electrodynamics architecture, is first introduced for applying a dc bias to a high-Q superconducting microwave cavity. The development and investigation of the cCPT system, in which a Cooper pair transistor acting as a single artificial atom is directly coupled to an on-chip dc-biased high-Q resonator, is then presented. Self-oscillations in the cCPT, internally driven by the ac Josephson effect, demonstrate the strong and phase coherent coupling between matter and light in the cCPT. Meanwhile, photons continually produced by the system are collected and characterized by quantum state tomography, which indicates the non-classical nature of the emitted light and the nonlinear quantum dynamics of the cCPT system.

  14. Characterizing the switching thresholds of magnetophoretic transistors

    PubMed Central

    Abedini-Nassab, Roozbeh; Joh, Daniel Y.; Van Heest, Melissa A.; Yi, John S.; Baker, Cody; Taherifard, Zohreh; Margolis, David M.; Garcia-Martinez, Victor; Chilkoti, Ashutosh; Murdoch, David M.; Yellen, Benjamin B.

    2015-01-01

    Here, we quantify for the first time the operating conditions of a 3-terminal magnetophoretic transistor architecture used to switch magnetically labeled single cells and single magnetic beads along different paths in microfluidic environments. The semiconducting transport properties are achieved by engineering a small gap between two magnetic disks. Cell and bead motion across the gap is controlled by the gate currents from nearby microwires, which produce competing magnetic fields to toggle the locations of the magnetic potential energy minima. We demonstrate both attractive and repulsive transistor modes, in which cells transfer towards the microwire (attractive mode) or away from microwire (repulsive mode). This novel two-way switching capability allows cells to be written to, or extracted from, specified storage areas in a multiplexed array. For both attractive and repulsive modes, we find that complete switching is achieved with as little as 10–20 mA gate currents in 0–100 Oe static and dynamic external magnetic fields. When combined with a non-fouling brush grafted to the chip surface to reduce non-specific cell adhesion, this platform opens the door to scalable, biologically relevant applications and multiplexing of large single cell arrays. PMID:26349853

  15. Coherent Matterwave Emission from an Atomtronic Transistor

    NASA Astrophysics Data System (ADS)

    Straatsma, Cameron; Anderson, Dana

    2016-05-01

    We investigate matterwave emission from a triple-well ``transistor'' atomic potential consisting of a ``source'' well treated as a reservoir having fixed chemical potential and temperature, a narrow ``gate'' well, and a ``drain'' well coupled to the vacuum. The ground state of the gate well is occupied by a Bose-Einstein condensate having large chemical potential along with the first excited state of the potential. These lower states are coupled to the two highest lying bound states lying near the top of the barriers separating the gate from the other two wells. We show that the energy level separations of the two lower states and the two upper states can be made degenerate by design of the Gaussian barrier widths and separation. When degenerate, the two pairs of states are strongly coupled by phonon exchange. We seek a self-consistent solution for the coupling between the high-lying states and the ground state pair, which occurs due to stimulated absorption and emission of phonons. In steady-state, coupling of the upper states leads to matter wave emission such that the emission of the two states is mutually coherent. The output from the transistor is thus an intensity-modulated matterwave whose frequency is approximately equal to the ground-state trap frequency.

  16. Electrostatically Reversible Polarity of Ambipolar α-MoTe2 Transistors.

    PubMed

    Nakaharai, Shu; Yamamoto, Mahito; Ueno, Keiji; Lin, Yen-Fu; Li, Song-Lin; Tsukagoshi, Kazuhito

    2015-06-23

    A doping-free transistor made of ambipolar α-phase molybdenum ditelluride (α-MoTe2) is proposed in which the transistor polarity (p-type and n-type) is electrostatically controlled by dual top gates. The voltage signal in one of the gates determines the transistor polarity, while the other gate modulates the drain current. We demonstrate the transistor operation experimentally, with electrostatically controlled polarity of both p- and n-type in a single transistor. PMID:25988597

  17. Linear control of oscillator and amplifier flows*

    NASA Astrophysics Data System (ADS)

    Schmid, Peter J.; Sipp, Denis

    2016-08-01

    Linear control applied to fluid systems near an equilibrium point has important applications for many flows of industrial or fundamental interest. In this article we give an exposition of tools and approaches for the design of control strategies for globally stable or unstable flows. For unstable oscillator flows a feedback configuration and a model-based approach is proposed, while for stable noise-amplifier flows a feedforward setup and an approach based on system identification is advocated. Model reduction and robustness issues are addressed for the oscillator case; statistical learning techniques are emphasized for the amplifier case. Effective suppression of global and convective instabilities could be demonstrated for either case, even though the system-identification approach results in a superior robustness to off-design conditions.

  18. Ideal photon number amplifier and duplicator

    NASA Technical Reports Server (NTRS)

    Dariano, G. M.

    1992-01-01

    The photon number-amplification and number-duplication mechanism are analyzed in the ideal case. The search for unitary evolutions leads to consider also a number-deamplification mechanism, the symmetry between amplification and deamplification being broken by the integer-value nature of the number operator. Both transformations, amplification and duplication, need an auxiliary field which, in the case of amplification, turns out to be amplified in the inverse way. Input-output energy conservation is accounted for using a classical pump or through frequency-conversion of the fields. Ignoring one of the fields is equivalent to considering the amplifier as an open system involving entropy production. The Hamiltonians of the ideal devices are given and compared with those of realistic systems.

  19. Review of two-stream amplifier performance

    NASA Astrophysics Data System (ADS)

    Phillips, Purobi M.; Freund, Henry P.; Zaidman, Ernest G.; Ganguly, Achintya K.; Vanderplaats, Norman R.

    1990-03-01

    The basic concept of the two-stream instability and its application in building a microwave/millimeter-wave amplifier are reviewed from the perspective of the general use of high-frequency devices. A historical review of the relevant literature is presented, with additional discussion of unpublished laboratory notebooks from the US Naval Research Laboratory. A summary of the theoretical background and its extension to the bounded three-dimensional case is given, along with results from one-dimensional nonlinear particle simulation, which is compared to nonlinear theory. The advantages, limitations, and shortcomings of a two-stream amplifier are discussed in comparison with other currently available devices that work in the same range of parameters.

  20. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1986-01-01

    In order to evaluate the feasibility of the solar pumped dye laser, the parametric study of a dye laser amplifier pumped by a solar simulator and flashlamp was carried out, and the amplifier gains were measured at various pump beam irradiances on the dye cell. Rhodamine 6G was considered as a candidate for the solar pumped laser because of its good utilization of the solar spectrum and high quantum efficiency. The measurement shows that a solar concentration of 20,000 is required to reach the threshold of the dye. The work to construct a kinetic model algorithm which predicts the output parameter of laser was progressed. The kinetic model was improved such that there is good agreement between the theoretical model and experimental data for the systems defined previously as flashlamp pumped laser oscillator, and the long path length solar pumped laser.