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Palma, F., Teppe, F., Fatimy, A. E., Green, R., Xu, J., Vachontin, Y., et al. (2010). THz communication system based on a THz quantum cascade laser and a hot electron bolometer. In 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves (11623798 (1 to 2)).
Abstract: We present the experimental study of the direct emission – detection system based on the THz Quantum Cascade Laser as a source and Hot Electron Bolometer (HEB) detector – in view of its application as an optical communication system. We show that the system can efficiently transmit the QCL Terahertz pulses. We estimate the maximal modulation speed of the system to be about several GHz and show that it is limited only by the QCL pulse power supply, detector amplifier and connection line/wires parameters.
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Shangina, E. L., Smirnov, K. V., Morozov, D. V., Kovalyuk, V. V., Gol’tsman, G. N., Verevkin, A. A., et al. (2010). Concentration dependence of the intermediate frequency bandwidth of submillimeter heterodyne AlGaAs/GaAs nanostructures. Bull. Russ. Acad. Sci. Phys., 74(1), 100–102.
Abstract: The concentration dependence of the intermediate frequency bandwidth of heterodyne AlGaAs/GaAs detectors with 2D electron gas is measured using submillimeter spectroscopy with high time resolution at T= 4.2 K. The intermediate frequency bandwidth f3dBfalls from 245 to 145 MHz with increasing concentration of 2D electrons n s = (1.6-6.6) × 10[su11] cm-2. The dependence f3dB ≈ n s – 0.04±is observed in the studied concentration range; this dependence is determined by electron scattering by the deformation potential of acoustic phonons and piezoelectric scattering.
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Mitin, V., Antipov, A., Sergeev, A., Vagidov, N., Eason, D., & Strasser, G. (2011). Quantum Dot Infrared Photodetectors: Photoresponse Enhancement Due to Potential Barriers. Nanoscale res lett, 6(1), 6.
Abstract: Potential barriers around quantum dots (QDs) play a key role in kinetics of photoelectrons. These barriers are always created, when electrons from dopants outside QDs fill the dots. Potential barriers suppress the capture processes of photoelectrons and increase the photoresponse. To directly investigate the effect of potential barriers on photoelectron kinetics, we fabricated several QD structures with different positions of dopants and various levels of doping. The potential barriers as a function of doping and dopant positions have been determined using nextnano3 software. We experimentally investigated the photoresponse to IR radiation as a function of the radiation frequency and voltage bias. We also measured the dark current in these QD structures. Our investigations show that the photoresponse increases ~30 times as the height of potential barriers changes from 30 to 130 meV.
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Семенов, А. В., Девятов, И. А., Рябчун, С. А., Масленников, С. Н., Масленникова, А. С., Ларионов, П. А., et al. (2011). Поглощение терагерцового электромагнитного излучения в “грязной” сверхпроводниковой пленке при произвольном виде спектральных функций. Ж. Радиоэлектрон., 10, 7.
Abstract: A problem of absorption of high-frequency electromagnetic field in dirty superconductor is treated within Keldysh technic. Expression for the source term in the kinetic equation for quasiparticle distribution function is derived. The result is significant for deriving a consistent microscopic theory of superconducting detectors for terahertz frequency range, perspective detectors on kinetic inductance of current-biased superconducting strip and on Josephson inductance of tunnel.
В технике Келдыша рассмотрена задача о поглощении мощности высокочастотного электромагнитного поля в сверхпроводнике, удовлетворяющем условию грязного предела. Получено выражение для члена источника в кинетическом уравнении для функции распределения квазичастиц, справедливое при произвольном виде спектральных функций. Этот результат имеет значение для развития последовательной микроскопической теории сверхпроводниковых детекторов излучения терагерцового диапазона, в частности, перспективных детекторов на кинетической индуктивности смещённой током сверхпроводниковой полоски и джозефсоновской индуктивности туннельного контакта.
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Semenov, A. V., Devyatov, I. A., Ryabchun, S. A., Maslennikov, S. N., Maslennikova, A. S., Larionov, P. A., et al. (2011). Absorption of terahertz electromagnetic radiation in dirty superconducting film at arbitrary type of the spectral functions. Rus. J. Radio Electron., (10).
Abstract: A problem of absorption of high-frequency electromagnetic field in dirty superconductor is treated within Keldysh technic. Expression for the source term in the kinetic equation for quasiparticle distribution function is derived. The result is significant for deriving a consistent microscopic theory of superconducting detectors for terahertz frequency range, perspective detectors on kinetic inductance of current-biased superconducting strip and on Josephson inductance of tunnel.
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