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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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D. Henrich, L. R. S. D., M. Hofherr, K. Il'in, A. Semenov, and M. Siegel. (2012). Detection efficiency of a spiral-nanowire superconducting single-photon detector. arXiv:1210.3988. Retrieved June 30, 2024, from http://arxiv.org/abs/1210.3988
Abstract: We investigate the detection efficiency of a spiral layout of a Superconducting Nanowire Single-Photon Detector (SNSPD). The design is less susceptible to the critical current reduction in sharp turns of the nanowire than the conventional meander design. Detector samples with different nanowire width from 300 to 100 nm are patterned from a 4 nm thick NbN film deposited on sapphire substrates. The critical current IC at 4.2 K for spiral, meander, and simple bridge structures is measured and compared. On the 100 nm wide samples, the detection efficiency is measured in the wavelength range 400-1700 nm and the cut-off wavelength of the hot-spot plateau is determined. In the optical range, the spiral detector reaches a detection efficiency of 27.6%, which is ~1.5 times the value of the meander. In the infrared range the detection efficiency is more than doubled.
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Minaeva, O., Fraine, A., Korneev, A., Divochiy, A., Goltsman, G., & Sergienko, A. (2012). High resolution optical time-domain reflectometry using superconducting single-photon detectors. In Frontiers in Opt. 2012/Laser Sci. XXVIII (Fw3a.39). Optical Society of America.
Abstract: We discuss the advantages and limitations of single-photon optical time-domain reflectometry with superconducting single-photon detectors. The higher two-point resolution can be achieved due to superior timing performance of SSPDs in comparison with InGaAs APDs.
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Чулкова, Г. М., Корнеев, А. А., Смирнов, К. В., & Окунев, О. В. (2012). Энергетическая релаксация в примесных металлах, двумерном электронном газе в AlGaAs-GaAs, сверхпроводниковых пленках NbN и детекторы субмиллиметрового и ик излучения на их основе. Прометей, МПГУ.
Abstract: Монография посвящена обзору исследований влияния эффектов электронного беспорядка на электронное взаимодействие в металлах, сверхпроводниках, полупроводниках, а также в различных низкоразмерных структурах. Актуальность поднятых в монографии вопросов определяется интенсивным развитием нанотехнологий, созданием новых наноструктурированных материалов и уникальных наноэлементов для электроники и фотоники. Упругое электронное рассеяние на границах наноструктур качественно меняет взаимодействие электронов с фонолами, что, безусловно, должно учитываться при проектировании соответствующей элементной базы. Прикладная часть работы посвящена контролируемой модификации электронных процессов для оптимизации новых наносенсоров на основе электронного разогрева в сверхпроводниковых и полупроводниковых структурах. Монография предназначена для студентов старших курсов, аспирантов и начинающих следователей, работающих в области сверхпроводниковой наноэлектроники.
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Shurakov, A., Tong, C. -yu E., Grimes, P., Blundell, R., & Golt'sman, G. (2015). A microwave reflection readout scheme for hot electron bolometric direct detector. IEEE Trans. THz Sci. Technol., 5, 81–84.
Abstract: In this paper, we propose and present data from a fast THz detector based on the repurpose of hot electron bolometer mixers (HEB) fabricated from superconducting NbN thinfilm. This detector is essentially a traditional NbN bolometer element that operates under the influence of a microwave pump. The in-jected microwave power serves the dual purpose of enhancing the detector sensitivity and reading out the impedance changes of the device in response to incidentTHz radiation. We have measured an optical Noise Equivalent Power of 4 pW/ Hz for our detector at a bath temperature of 4.2 K. The measurement frequency was 0.83 THz and the modulation frequency was 1.48 kHz. The readout
scheme is versatile and facilitates both high-speed operation as well as multi-pixel applications.
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Gayduchenko, I., Kardakova, A., Fedorov, G., Voronov, B., Finkel, M., Jiménez, D., et al. (2015). Response of asymmetric carbon nanotube network devices to sub-terahertz and terahertz radiation. J. Appl. Phys., 118(19), 194303.
Abstract: Demand for efficient terahertz radiation detectors resulted in intensive study of the asymmetric carbon nanostructures as a possible solution for that problem. It was maintained that photothermoelectric effect under certain conditions results in strong response of such devices to terahertz radiation even at room temperature. In this work, we investigate different mechanisms underlying the response of asymmetric carbon nanotube (CNT) based devices to sub-terahertz and terahertz radiation. Our structures are formed with CNT networks instead of individual CNTs so that effects probed are more generic and not caused by peculiarities of an individual nanoscale object. We conclude that the DC voltage response observed in our structures is not only thermal in origin. So called diode-type response caused by asymmetry of the device IV characteristic turns out to be dominant at room temperature. Quantitative analysis provides further routes for the optimization of the device configuration, which may result in appearance of novel terahertz radiation detectors.
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Dube, I., Jiménez, D., Fedorov, G., Boyd, A., Gayduchenko, I., Paranjape, M., et al. (2015). Understanding the electrical response and sensing mechanism of carbon-nanotube-based gas sensors. Carbon, 87, 330–337.
Abstract: Gas sensors based on carbon nanotube field effect transistors (CNFETs) have outstanding sensitivity compared to existing technologies. However, the lack of understanding of the sensing mechanism has greatly hindered progress on calibration standards and customization of these nano-sensors. Calibration requires identifying fundamental transistor parameters and establishing how they vary in the presence of a gas. This work focuses on modeling the electrical response of CNTFETs in the presence of oxidizing (NO2) and reducing (NH3) gases and determining how the transistor characteristics are affected by gas-induced changes of contact properties, such as the Schottky barrier height and width, and by the doping level of the nanotube. From the theoretical fits of the experimental transfer characteristics at different concentrations of NO2 and NH3, we find that the CNTFET response can be modeled by introducing changes in the Schottky barrier height. These changes are directly related to the changes in the metal work function of the electrodes that we determine experimentally, independently, with a Kelvin probe. Our analysis yields a direct correlation between the ON – current and the changes in the electrode metal work function. Doping due to molecules adsorbed at the carbon-nanotube/metal interface also affects the transfer characteristics.
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Akhmadishina, K. F., Bobrinetskiy, I. I., Komarov, I. A., Malovichko, A. M., Nevolin, V. K., Fedorov, G. E., et al. (2015). Fast-response biological sensors based on single-layer carbon nanotubes modified with specific aptamers. Semicond., 49(13), 1749–1753.
Abstract: The possibility of the fabrication of a fast-response biological sensor based on a composite of single-layer carbon nanotubes and aptamers for the specific detection of proteins is shown. The effect of modification of the surface of the carbon nanotubes on the selectivity and sensitivity of the sensors is investigated. It is shown that carboxylated nanotubes have a better selectivity for detecting thrombin.
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