The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform

V. V. Popov - One of the best experts on this subject based on the ideXlab platform.

  • The Resonant Terahertz Response of a Slot Diode with a Two-Dimensional Electron Channel
    Semiconductors, 2020
    Co-Authors: V. V. Popov
    Abstract:

    The terahertz response of a slot diode with a two-dimensional Electron Channel is calculated on the basis of the first principles of electromagnetism. It is shown that all characteristic electromagnetic lengths (scattering, absorption, and extinction lengths), as well as the impedance of the diode, exhibit resonances at plasmon excitation frequencies in the Channel. The fundamental resonance behaves similarly to the current resonance in an RLC circuit. It has been concluded that, even at room temperature, a slot diode with a two-dimensional Electron Channel provides a resonant circuit at terahertz frequencies that couples effectively to external electromagnetic radiation with a loaded Q-factor exceeding unity. The diode resistance may be measured from contactless measurements of the characteristic electromagnetic lengths of the diode.

  • Plasmonic terahertz monochromatic coherent emission from an asymmetric chirped dual-grating-gate InP-HEMT with a photonic vertical cavity
    71st Device Research Conference, 2013
    Co-Authors: Takayuki Watanabe, V. V. Popov, Akira Satou, Yuki Kurita, Tetsuya Suemitsu, Wojciech Knap, Taiichi Otsuji
    Abstract:

    We demonstrate an intense stimulated emission of 0.1-1-μW terahertz (THz) monochromatic radiation in InP-based asymmetric chirped dual-grating-gate (AC-DGG) high Electron mobility transistors (HEMTs) at 140-290K. In the research of modern THz Electronics, development of compact, tunable and coherent sources operating in the THz regime is one of the hottest issues. Hydrodynamic nonlinearities of two-dimensional (2D) plasmons in HEMTs are promising for intense emission of THz radiation [1, 2]. Thanks to the dc-current-driven plasmon instabilities of the Dyakonov-Shur (D-S) type driven by a non-reciprocal Doppler effect in 2D Electron Channel with asymmetric boundary conditions [1] and/or the Ryzhii-Satou-Shur (R-S-S) type driven by Electron-transit-time mechanism in a periodic structure [3] the gate-voltage tunable THz emission has been observed from GaN-, GaAs- and InP-based single-gate or symmetric dual-grating-gate (DGG) HEMTs [4-6].

  • transformation of the plasmon spectrum in a grating gate transistor structure with spatially modulated two dimensional Electron Channel
    Semiconductors, 2010
    Co-Authors: D V Fateev, V. V. Popov, M S Shur
    Abstract:

    We present the theory of plasmon excitation in a grating-gate transistor structure with spatially modulated 2D Electron Channel. The plasmon spectrum varies depending on the Electron density modulation in the transistor Channel. We report on the frequency ranges of plasmon mode excitation in the gated and ungated regions of the Channel and on the interaction of these different types of plasmon modes. We show that a constructive influence of the ungated regions of the Electron Channel considerably increases the intensity of the gated plasmon resonances and reduces the plasmon-resonance linewidth in the grating-gated transistor structure.

  • Plasmon-plasmon scattering in two-dimensional Electron Channel of a terahertz nanotransistor
    2008 4th International Conference on Advanced Optoelectronics and Lasers, 2008
    Co-Authors: Olga V. Polischuk, V. V. Popov, W. Knap, El A. Fatimy
    Abstract:

    We calculate the terahertz absorption spectrum of the high-Electron-mobility transistor with a short gate and long ungated Channel regions and show that the main contribution to the linewidth of the gated plasmon resonance can be attributed to the plasmon-plasmon inter-mode scattering. The results allow to interpret recent experimental results of resonant THz detection by InGaAs nanotransistors. The physics of the plasmon-plasmon inter-mode scattering is discussed compared to the other possible plasmon damping mechanisms.

  • terahertz plasmon photoresponse in a density modulated two dimensional Electron Channel of a gaas algaas field effect transistor
    Applied Physics Letters, 2007
    Co-Authors: G. Aizin, G. M. Tsymbalov, D V Fateev, V. V. Popov
    Abstract:

    We present a theory of dc photoresponse, change in device conductance, at the plasmon resonance in the density modulated two-dimensional Electron Channel of the grating-gated GaAs∕AlGaAs field-effect transistor irradiated by an electromagnetic wave of terahertz frequency. An equilibrium density modulation is shown to give rise to a specific mechanism of photoresponse due to a plasma electrostriction effect. In strongly modulated systems, this effect dominates the photoresponse and results in a strong increase of the resonant peak amplitudes and photoresponse sign reversal dependent on the modulation depth and the equilibrium density profile. These results are in good qualitative agreement with recent experiments.

M. Miyashita - One of the best experts on this subject based on the ideXlab platform.

  • dependence of Electron Channel mobility on si sio sub 2 interface microroughness
    IEEE Electron Device Letters, 1991
    Co-Authors: T. Ohmi, K. Kotani, A. Teramoto, M. Miyashita
    Abstract:

    The effect of the Si-SiO/sub 2/ interface microroughness on the Electron Channel mobility of n-MOSFETs was investigated. The surface microroughness was controlled by changing the mixing ratio of NH/sub 4/OH in the NH/sub 4/OH-H/sub 2/O/sub 2/-H/sub 2/O solution in the RCA cleaning procedure. The gate oxide was etched, following the evaluation of the electrical characteristics of MOS transistors, to measure the microroughness of the Si-SiO/sub 2/ interface with scanning tunneling microscopy (STM). As the interface microroughness increases, the Electron Channel mobility, which can be obtained from the current-voltage characteristics of the MOSFET, gets lower. The Channel mobility is around 360 cm/sup 2//V-s when the average interface microroughness is 0.2 nm, where the substrate impurity concentration is 4.5*10/sup 17/ cm/sup -3/, i.e. the Electron bulk mobility is 400 cm/sup 2//V-s. It goes down to 100 cm/sup 2//V-s when the interface microroughness exceeds 1 nm. >

  • Dependence of Electron Channel mobility on Si-SiO/sub 2/ interface microroughness
    IEEE Electron Device Letters, 1991
    Co-Authors: T. Ohmi, K. Kotani, A. Teramoto, M. Miyashita
    Abstract:

    The effect of the Si-SiO/sub 2/ interface microroughness on the Electron Channel mobility of n-MOSFETs was investigated. The surface microroughness was controlled by changing the mixing ratio of NH/sub 4/OH in the NH/sub 4/OH-H/sub 2/O/sub 2/-H/sub 2/O solution in the RCA cleaning procedure. The gate oxide was etched, following the evaluation of the electrical characteristics of MOS transistors, to measure the microroughness of the Si-SiO/sub 2/ interface with scanning tunneling microscopy (STM). As the interface microroughness increases, the Electron Channel mobility, which can be obtained from the current-voltage characteristics of the MOSFET, gets lower. The Channel mobility is around 360 cm/sup 2//V-s when the average interface microroughness is 0.2 nm, where the substrate impurity concentration is 4.5*10/sup 17/ cm/sup -3/, i.e. the Electron bulk mobility is 400 cm/sup 2//V-s. It goes down to 100 cm/sup 2//V-s when the interface microroughness exceeds 1 nm.

O.v. Polischuk - One of the best experts on this subject based on the ideXlab platform.

  • tuning of ungated plasmons by a gate in the field effect transistor with two dimensional Electron Channel
    Journal of Applied Physics, 2008
    Co-Authors: V V Popov, M S Shur, A N Koudymov, O.v. Polischuk
    Abstract:

    We show that voltage variations at a short gate can effectively tune higher-order ungated plasmon resonances in field-effect transistors (FETs). These higher-order ungated plasmon resonances may be excited by incoming terahertz radiation with much greater efficiency than the gated plasmon resonances. We calculate the spectra of the terahertz plasmon absorption in the frame of a rigorous electromagnetic approach, which allows us to estimate the radiation resistance. Based on the calculation results, we explain the behavior of different plasmon resonances in terms of the alternating-current FET equivalent circuit. The results may help design high performance plasmonic devices operating in the terahertz frequency range.

  • Tunable Screening of Inter-Contact Plasmons by a Recessed Gate in Field-Effect Transistor with Two-Dimensional Electron Channel
    2007 International Kharkov Symposium Physics and Engrg. of Millimeter and Sub-Millimeter Waves (MSMW), 2007
    Co-Authors: V. V. Popov, O.v. Polischuk, T.v. Teperik
    Abstract:

    This work studies field-effect transistors (FET) with two-dimensional Electron Channel. It is theoretically shown that the frequencies of higher-order resonances of the ungated plasmon modes can be effectively tuned by the gate-voltage variation at a short recessed gate, which mimic conventional gated plasmon resonance but with a much stronger efficiency. The calculated THz absorption spectra of a FET with a short recessed gate are presented. Results show that the frequency of the second-order inter-contact plasmon resonance can be tuned by applying the gate voltage producing the Electron density variation in the short gated region of the Channel.

  • plasmon enhanced Electron drag and terahertz photoconductance in a grating gated field effect transistor with two dimensional Electron Channel
    Applied Physics Letters, 2006
    Co-Authors: G. Aizin, V. V. Popov, O.v. Polischuk
    Abstract:

    The authors present a theory of dc photoresponse in two-dimensional (2D) Electron Channel in the grating-gated field-effect transistor irradiated by an electromagnetic wave of terahertz frequency. The authors determine photoinduced dc correction to the source-drain voltage and demonstrate that it has resonant peaks when the frequency of an external radiation coincides with 2D plasmon frequencies. The photoresponse is shown to depend on the asymmetric Electron drag in the 2D Channel with constant bias current. The amplitude of the resonant peaks has nonmonotonic temperature dependence with a maximum at elevated temperatures. The results explain qualitatively some important features of the photoresponse observed in recent experiments.

  • Electrodynamics of plasma oscillations in semiconductor microdevices with two-dimensional Electron Channels
    10th International Conference on Mathematical Methods in Electromagnetic Theory 2004., 2004
    Co-Authors: V. V. Popov, G. M. Tsymbalov, O.v. Polischuk, W. Knap
    Abstract:

    Electromagnetic theory of plasma oscillations in field-effect transistor with two-dimensional Electron Channel is presented. Two different key electromagnetic problems are considered. They are the problems of diffraction of the plane electromagnetic wave (i) on the slot in infinite perfectly conductive plane, which is bridged by 2D Electron Channel and (ii) on the perfectly conductive strip, which screens partially an infinite 2D Electron sheet located at a given distance from the strip. New physics inherent in these problems is revealed.

T. Ohmi - One of the best experts on this subject based on the ideXlab platform.

  • dependence of Electron Channel mobility on si sio sub 2 interface microroughness
    IEEE Electron Device Letters, 1991
    Co-Authors: T. Ohmi, K. Kotani, A. Teramoto, M. Miyashita
    Abstract:

    The effect of the Si-SiO/sub 2/ interface microroughness on the Electron Channel mobility of n-MOSFETs was investigated. The surface microroughness was controlled by changing the mixing ratio of NH/sub 4/OH in the NH/sub 4/OH-H/sub 2/O/sub 2/-H/sub 2/O solution in the RCA cleaning procedure. The gate oxide was etched, following the evaluation of the electrical characteristics of MOS transistors, to measure the microroughness of the Si-SiO/sub 2/ interface with scanning tunneling microscopy (STM). As the interface microroughness increases, the Electron Channel mobility, which can be obtained from the current-voltage characteristics of the MOSFET, gets lower. The Channel mobility is around 360 cm/sup 2//V-s when the average interface microroughness is 0.2 nm, where the substrate impurity concentration is 4.5*10/sup 17/ cm/sup -3/, i.e. the Electron bulk mobility is 400 cm/sup 2//V-s. It goes down to 100 cm/sup 2//V-s when the interface microroughness exceeds 1 nm. >

  • Dependence of Electron Channel mobility on Si-SiO/sub 2/ interface microroughness
    IEEE Electron Device Letters, 1991
    Co-Authors: T. Ohmi, K. Kotani, A. Teramoto, M. Miyashita
    Abstract:

    The effect of the Si-SiO/sub 2/ interface microroughness on the Electron Channel mobility of n-MOSFETs was investigated. The surface microroughness was controlled by changing the mixing ratio of NH/sub 4/OH in the NH/sub 4/OH-H/sub 2/O/sub 2/-H/sub 2/O solution in the RCA cleaning procedure. The gate oxide was etched, following the evaluation of the electrical characteristics of MOS transistors, to measure the microroughness of the Si-SiO/sub 2/ interface with scanning tunneling microscopy (STM). As the interface microroughness increases, the Electron Channel mobility, which can be obtained from the current-voltage characteristics of the MOSFET, gets lower. The Channel mobility is around 360 cm/sup 2//V-s when the average interface microroughness is 0.2 nm, where the substrate impurity concentration is 4.5*10/sup 17/ cm/sup -3/, i.e. the Electron bulk mobility is 400 cm/sup 2//V-s. It goes down to 100 cm/sup 2//V-s when the interface microroughness exceeds 1 nm.

Yu. P. Yakovlev - One of the best experts on this subject based on the ideXlab platform.

  • Magnetotransport properties of type II heterojunctions based on GaInAsSb/InAs and GaInAsSb/GaSb
    Semiconductors, 2006
    Co-Authors: T. I. Voronina, T. S. Lagunova, M. P. Mikhaĭlova, K. D. Moiseev, A. F. Lipaev, Yu. P. Yakovlev
    Abstract:

    The results of detailed study of the magnetotransport properties of broken-gap type II heterojunctions in a GaInAsSb/InAs(GaSb) system are reported. An Electron Channel with a high charge-carrier mobility (as high as 50000–60000 cm^2/(V s)) is observed and studied for the first time in an isotype broken-gap p -GaInAsSb/ p -InAs heterostructure. The effects of Electron-Channel depletion and semimetal-semiconductor transition in the case of heavy doping of the quaternary alloy with acceptors are studied. Magnetotransport properties at temperatures of 4.2–200 K are studied in detail. Data on the energy spectrum and parameters of two-dimensional charge carriers at the heteroboundary are obtained. It is ascertained experimentally that, depending on the composition, either staggered (at x = 0.85) or broken-gap (at x = 0.95) heterojunctions can be formed in the Ga_1− x In_xAs_ySb_1− y /GaSb, which is confirmed by theoretical calculations. The anomalous Hall effect and negative magnetoresistance were observed in GaInAsSb/InAs:Mn grown on substrates doped heavily with Mn magnetic acceptor impurity so that the hole concentration was as high as p > 5 × 10^18 cm^−3; these phenomena are caused by exchange interaction of Mn ions in InAs with high-mobility charge carriers in the Electron Channel at the heterointerface.

  • interface induced optical and transport phenomena in type ii broken gap single heterojunctions
    Semiconductor Science and Technology, 2004
    Co-Authors: M. P. Mikhailova, K. D. Moiseev, Yu. P. Yakovlev
    Abstract:

    This review deals with a study of optical and magnetotransport phenomena at a type II arsenide–antimonide heterojunction with a broken-gap alignment. A fundamental feature of this structure is partial overlapping of the InAs conduction band with the GaSb-rich solid solution valence band. In such a heterostructure, Electrons and holes are spatially separated and localized in self-consistent quantum wells formed on both sides of the heterointerface. This leads to unusual tunnelling-assisted radiative recombination transitions and novel transport properties. Results of a pioneering study of interface-related luminescence in type II broken-gap GaInAsSb/InAs heterostructures, with a high quality abrupt heteroboundary, grown by the LPE method, are presented. The energy band diagram of the type II broken-gap GaInAsSb/InAs(GaSb) heterostructures and band overlapping control, depending on a doping level and epilayer composition of quaternary solid solution, are discussed. A 2D-Electron Channel with high Hall mobility at the p-GaInAsSb/p-InAs interface was found and examined. A great deal of attention is paid to quantum transport properties of the semimetal Channel in a wide magnetic field range (up to 18 T) at low temperatures. A cyclotron resonance study was used to obtain data on the energy spectrum at the interface and to estimate effective masses for subbands in the semimetal Channel. The intriguing behaviour of the 2D-Electron system in the presence of localized holes in high magnetic fields and the first observation of integer quantum Hall effect plateaus on the type II single GaInAsSb/InAs heterointerface formed by LPE are demonstrated. A tunnelling-injection laser with high asymmetric band offset confinements based on the type II broken-gap heterojunction is considered. Applications of the interface-induced phenomena in luminescent and transport properties for the design of novel mid-IR optoElectronic devices and Hall sensors are briefly reviewed.

  • Interaction of charge carriers with the localized magnetic moments of manganese atoms in p-GaInAsSb/p-InAs:Mn heterostructures
    Semiconductors, 2003
    Co-Authors: T. S. Lagunova, T. I. Voronina, M. P. Mikhailova, K. D. Moiseev, E. Samokhin, Yu. P. Yakovlev
    Abstract:

    Transport properties of p -Ga_1− x In_xAs_ySb_1− y / p -InAs:Mn heterostructures with undoped layers of solid solutions similar in composition to GaSb ( x ≲0.22) grown by liquid-phase epitaxy on substrates with a Mn concentration of (5–7)×10^18 cm^−3 are studied. It is ascertained that there is an Electron Channel at the interface (from the InAs side). The anomalous Hall effect and negative magnetoresistance are observed at relatively high temperatures (77–200) K. These phenomena can be attributed to the s-d -exchange interaction between Mn ions of the substrate and s Electrons of the two-dimensional Channel. The effective magnetic moment of Mn ions was evaluated as μ=200µ_B at T =77 K.

  • Interface-induced phenomena in type II antimonide-arsenide heterostructures
    IEE Proceedings - Optoelectronics, 1998
    Co-Authors: M. P. Mikhailova, K. D. Moiseev, Y.a. Berezovets, R.v. Parfeniev, N.l. Bazhenov, V.a. Smirnov, Yu. P. Yakovlev
    Abstract:

    Type II antimonide-arsenide based heterostructures have recently received great attention from researchers engaged in the design of mid-infrared optoElectronic devices. Magnetotransport properties of the semimetal Channel and the interface electroluminescence were experimentally studied on type II broken-gap GaInAsSb-InAs single heterojunctions grown by LPE with high quality interface. An Electron Channel with high Hall mobility was, for the first time, observed at the interface of isotype p-GaInAsSb/p-InAs heterojunctions with undoped and slightly doped quaternary layers at low temperatures. A depletion of the Electron Channel was found to be due to the heavy acceptor doping level of the quaternary layer. The two-dimensional nature of the interface carriers was established by Shubnikov-de Haas oscillation experiments at 1.8-4.2 K under magnetic fields up to 9-14 T. Intensive interface electroluminescence in the structures under study was observed in the spectral range of 3-4 /spl mu/m at low temperatures (4.2-77 K). A model of the recombination transition at the type II broken-gap interface was proposed and experimentally confirmed. A new physical approach to the design of mid-infrared tunnelling-injection lasers is demonstrated.

  • Properties of the Electron Channel in single GaInAsSb/p-InAs heterostructures
    Technical Physics Letters, 1997
    Co-Authors: T. I. Voronina, T. S. Lagunov, M. P. Mikhailova, Konstantin D. Moiseev, S. A. Obukhov, A. E. Rozov, Yu. P. Yakovlev
    Abstract:

    An investigation is carried out on the properties of the Electron Channel in a broken-gap isotypic type II GaInAsSb/p-InAs heterostructure and their dependence on the doping level of the quaternary solid solution with a donor (Te) and an acceptor (Zn). The Hall mobility decreases (by more than two orders of magnitude) with increasing acceptor concentration. The Shubnikov-de Haas oscillations are observed at low temperatures (T=1.5–20 K) and the Electron effective mass is determined (mn=0.026m0), along with some other parameters of the heterostructure.