Hydyrova Selbi

Scopus Publications

Investigation of Electrical Properties and Structure of ITO Thin Films Fabricated by Magnetron Sputtering
Selbi Yu Hydyrova, Kamila T. Makarova, Mikhail G. Popkov, Timur I. Mavliaviev, Sergei S. Romanov, et al.
International Youth Conference on Radio Electronics Electrical and Power Engineering Reepe, 2025
In this paper, electrical properties of thin ITO films formed by magnetron sputtering on Si, sapphire, Si3N4 on Si substrates, as well as on polyvinylidene fluoride and a glass slide, depending on the deposition process parameters were investigated. A characteristic power-law dependence of the sheet resistance on the film thickness was obtained in the thickness range from 20 to 100 nm. Process modes were determined that provide the lowest sheet resistance values from 98 to 155 Ohm/sq. for 100 nm thick films during formation without heating the substrate and direct current sputtering at a magnetron power of 80 to 85 W. It was revealed that sputtering in a pulsed mode at a pulse frequency of 10 to 100 kHz and a pulse duty cycle of 15 to 80% leads to an increase in the sheet resistance of the films in the range under study. Heating the substrate holder to 200°C during formation leads to an increase in the degree of crystallinity of the film and a decrease in the sheet resistance to 71 Ohm/sq. and 77 Ohm/sq. for ITO on Si and sapphire substrates, respectively. On polyvinylidene fluoride substrates, the highest transmittance of the ITO film is 86% at a wavelength of 550 nm.
Waveguide Integrated Superconducting Single-Photon Detector For Photonic And Ion Quantum Processors And Neuromorphic Computing
V. V. Kovalyuk, I. O. Venediktov, K. O. Sedykh, S. S. Svyatodukh, S. Hydyrova, et al.
Radiophysics and Quantum Electronics, 2024
Study of the Influence of Substrate Material and Thickness of Indium Tin Oxide Coatings on Their Optoelectronic Characteristics
P. A. Mikhalev, B. A. Parshin, S. Y. Hydyrova, K. M. Moiseev, A. S. Voronin
2024 Intelligent Technologies and Electronic Devices in Vehicle and Road Transport Complex Tirved 2024 Conference Proceedings, 2024
The article presents the results of studies on the influence of substrate material, application parameters, and Indium Tin Oxide (ITO) coating thickness on its functional characteristics (transparency and surface resistance). Coatings of different thicknesses were applied by magnetron sputtering to two types of substrates: glass and polyethylene terephthalate (PET) film. The optical parameters were studied using spectrophotometry (in the visible wavelength range), while the surface resistance was measured using the four-point van der Pauw method. As a result, the optimal values of the application parameters and ITO coating thickness for each type of substrate were determined, balancing transparency and surface resistance, with a view to their subsequent use as transparent electrodes in microelectronics, optoelectronics, acousto-optics, solar energy, and other fields.
Wavelength-and Time-Division Multiplexing via Pump Current Variation of a Pulsed Semiconductor Laser-A Method of Synchronization for Quantum Key Distribution
Roman Shakhovoy, Marius Puplauskis, Violetta Sharoglazova, Elizaveta Maksimova, Selbi Hydyrova, et al.
IEEE Journal of Quantum Electronics, 2023
The dependence of the semiconductor laser wavelength on the pump current is a well-known phenomenon, which is generally attributed to a change in the refractive index of the active layer due to carrier injection. This effect is usually considered to be a drawback as it causes frequency chirping of the pulses produced via direct current modulation. Here, we show that at high values of thermal resistance of a laser diode, the lasing wavelength is red-shifted due to the change of the refractive index caused by a thermal effect and this shift may significantly exceed (in absolute value) the blue shift related to a refractive index change induced by the carrier injection. We propose to benefit from the ability to tune wavelength by the pump current variation and use the same laser to generate qubits and synchronization optical pulses for quantum key distribution at different wavelengths. To demonstrate the proposed method of synchronization, we perform numerical simulations as well as proof-of-principle experiments.
Temperature rate equations for a semiconductor laser
Selbi Hydyrova, Marius Puplauskis, Roman Shakhovoy
Aip Conference Proceedings, 2023
Phase randomness in a semiconductor laser: Issue of quantum random-number generation
Roman Shakhovoy, Marius Puplauskis, Violetta Sharoglazova, Alexander Duplinskiy, Denis Sych, et al.
Physical Review A, 2023
Gain-switched lasers are in demand in numerous quantum applications, particularly, in systems of quantum key distribution and in various optical quantum random number generators. The reason for this popularity is natural phase randomization between gain-switched laser pulses. The idea of such randomization has become so familiar that most authors use it without regard to the features of the laser operation mode they use. However, at high repetition rates of laser pulses or when pulses are generated at a bias current close to the threshold, the phase randomization condition may be violated. This paper describes theoretical and experimental methods for estimating the degree of phase randomization in a gain-switched laser. We consider in detail diﬀerent situations of laser pulse interference and show that the interference signal remains quantum in nature even in the presence of classical phase drift in the interferometer provided that the phase diﬀusion in a laser is eﬃcient enough. Moreover, we formulate the relationship between the previously introduced quantum reduction factor and the leftover hash lemma. Using this relationship, we develop a method to estimate the quantum noise contribution to the interference signal in the presence of phase correlations. Finally, we introduce a simple experimental method based on the analysis of statistical interference fringes, providing more detailed information about the probabilistic properties of laser pulse
Review of Superconducting Microstrip Single-photon Detectors
В.А. Желтиков, Д.Д. Платонов, С. Хадырова, К.М. Моисеев, Д.Д. Васильев
Photonics Russia, 2022
В работе описаны актуальные модели детектирования и текущее состояние развития техники однофотонных детекторов. Проведен анализ материалов изготовления ультратонких пленок для детекторов, структура которых создана на основе полосок микрометровой ширины (SMSPD), и составлены рекомендации для улучшения их рабочих характеристик. Для снижения скорости темнового счета (DCR), возрастания эффективности детектирования системы (SDE), быстродействия (CR) и увеличения активной площади необходимо использовать SMSPD из рентгеноаморфных материалов типа α-Mn с низким коэффициентом диффузии, обладающих топологией, созданной на основе брэгговских отражающих структур (DBR), с высоким коэффициентом заполнения и уширением полосы элементов на повороте.
Evaluation of the Single-Photon Detector Characteristics Depending on the Parameters of a WxSi1–x Superconducting Film
S. Yu. Hydyrova, I. A. Stepanov, D. D. Vasilev, K. M. Moiseev
Physics of the Solid State, 2021
Providing of Ultra-Thin Film Thickness Uniformity by Magnetron Sputtering from Two Sources
S Hydyrova, M Yu Akishin, D D Vasilev, K M Moiseev
Iop Conference Series Materials Science and Engineering, 2020
To achieve high characteristics of single-photon detectors based on WSi thin films it is necessary to provide high film thickness uniformity more than 95%. This paper presents a mathematical modeling of the thickness uniformity of an ultra-thin film formed by magnetron sputtering from two sources, based on an experimentally determined mass flow from a single magnetron, depending on the location of the magnetrons relative to the substrate holder. According to the results of non-uniformity modeling, the requirements for the design and location of the magnetron unit in the chamber were made, which ensured the required non-uniformity of the film thickness of less than 5%.
Simulation of the cut-off wavelength of superconducting single-photon detectors based on WSi thin films for systems for optical space communications
K. M. Moiseev, D. D. Vasilev, S. Yu. Hydyrova
Aip Conference Proceedings, 2019
Superconducting single-photon detectors (SNSPD) are receivers in optical systems for space communications and exhibit high quantum efficiency and count rate. The receiver in the optical system of atmospheric communication should provide highly efficient detection of radiation with a wavelength of 1.55 µm. The cut-off wavelength of SNSPD is the maximum wavelength of radiation at which high detection efficiency is maintained and depends on the geometrical parameters of the sensitive element of the detector and the thickness and structure of the thin film of superconducting material parameters. In this work, we simulate the cut-off wavelength depending on the thickness of the superconducting film WxSi1-x and the stoichiometric composition with a nanowire width of 100 nm and a ratio of the bias current to the critical 0.7. It is shown that the largest value of the cut-off wavelength λc = 3.06 µm corresponds to a film thickness of 5 nm and a Si content of 25%. With a film thickness of 7 nm, detection with the required wavelength of 1.55 µm is provided over the entire investigated range of the stoichiometric composition of the film: when the Si content is from 15 to 25%.Superconducting single-photon detectors (SNSPD) are receivers in optical systems for space communications and exhibit high quantum efficiency and count rate. The receiver in the optical system of atmospheric communication should provide highly efficient detection of radiation with a wavelength of 1.55 µm. The cut-off wavelength of SNSPD is the maximum wavelength of radiation at which high detection efficiency is maintained and depends on the geometrical parameters of the sensitive element of the detector and the thickness and structure of the thin film of superconducting material parameters. In this work, we simulate the cut-off wavelength depending on the thickness of the superconducting film WxSi1-x and the stoichiometric composition with a nanowire width of 100 nm and a ratio of the bias current to the critical 0.7. It is shown that the largest value of the cut-off wavelength λc = 3.06 µm corresponds to a film thickness of 5 nm and a Si content of 25%. With a film thickness of 7 nm, detection with the ...