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Photoconductivity and infrared-light absorption in p-GaAs/AlGaAs quantum wells
Semiconductors. 2022. Vol. 55. No. 9. P. 710-716.
Vinnichenko M. Y., Makhov I., Kharin N. Y., Graf S. V., Panevin V. Y., Sedova I. V., Sorokin S. V., Firsov D. A.
The low-temperature impurity-assisted photoconductivity and absorption spectra of a nanostructure
with acceptor-doped multiple GaAs/AlGaAs quantum wells are investigated. The experimental absorption
and photoconductivity spectra agree well with each other. Using the calculated energy spectrum of the
hole and acceptor states in the quantum wells, the contributions of the transitions of holes from the ground
acceptor state to the delocalized states of valence subbands and excited impurity states, and the contributions
of the acceptor photoionization to the states above a quantum well, are identified.
Nikolaev I., Kazakov A., Drozdov K. et al., Journal of Applied Physics 2022 Vol. 132 No. 23 Article 234301
We report a detailed study of the bipolar persistent photoconductivity in an HgTe/CdHgTe double quantum well (DQW), which can be a perspective for studying topological states in these structures. Photoconductivity spectra measurements in the range of 1.1–3.1 eV as well as transport measurements under different illumination conditions were performed at T = 4.2 K. Based on the results, the processes ...
Added: June 7, 2023
Adamov R. B., Melentev G. A., Sedova I. V. et al., Journal of Luminescence 2024 Vol. 266 Article 120302
Terahertz (THz) luminescence in doped nanostructures with GaAs/AlGaAs quantum wells is studied under conditions of interband optical pumping. The study is carried out on compensated quantum wells with different doping profiles. In one structure, compensation is carried out directly in each quantum well by introducing donors and acceptors with the same concentration. In the other, ...
Added: November 12, 2023
Nadtochiy A., Gordeev N., Kharchenko A. et al., Journal of Lightwave Technology 2021 Vol. 39 No. 23 P. 7479-7485
Modal absorptions in laser-like heterostructures containing
InAs self-assembled quantum dots (QDs) and InGaAs
quantum well-dots (QWDs) have been studied. The evaluation
of photoresponse as a function of waveguide length has allowed
us to determine per-layer modal absorptions of 69 and 13 cm-1
for the ground state optical transitions of QWDs and QDs, respectively.
The values of the modal absorption can be ...
Added: November 28, 2021
Vinnichenko M. Y., Makhov I., Ustimenko R. V. et al., Micro and Nanostructures 2022 Vol. 169 Article 207339
The results of comprehensive studies of near-infrared photoluminescence and mid-infrared equilibrium and photoinduced absorption spectra in structures with Ge/Si quantum dots with different doping levels at different optical pumping intensities and different temperatures are presented. Obtained dependences of interband photoluminescence spectra on temperature and optical pumping intensity are explained by the change in the intensities of direct and indirect in real space electron-hole ...
Added: September 5, 2022
Максимов М. В., Zhukov A., Письма в Журнал технической физики 2019 Т. 45 № 11 С. 20-23
InGaAs/InGaAlAs laser diodes operating in the 1.55-μm spectral range are studied. It is demonstrated
that a certain level of carbon doping (1012 cm–2 per a single quantum well) allows one to reduce the
temperature coefficient of variation of the lasing wavelength in such structures and raise the characteristic
temperature of threshold current and differential efficiency at temperatures from ...
Added: March 16, 2021
Moiseev E., Максимов М. В., Kryzhanovskaya N. et al., Физика и техника полупроводников 2020 Т. 54 № 2 С. 212-216
The results are presented on a comparative analysis of spectral and threshold characteristics of diode microdisk lasers operating at room temperature in a spectral range of 1.2xx µm with different active regions: InGaAsN/GaAs quantum wells or InAs/InGaAs/GaAs quantum dots. It was found that microlasers of a comparable size with quantum wells have higher lasing threshold ...
Added: September 30, 2020
Malov V. V., Tameev A. R., Novikov S. V. et al., Organic Photonics and Photovoltaics 2015 Vol. 3 No. 1 P. 156-160
Optical and photoelectric properties of modern photosensitive polymers are of great interest due to their prospects for photovoltaic applications. In particular, an investigation of absorption and photoconductivity edge of these materials could provide valuable information. For these purpose we applied the constant photocurrent method which has proved its efficiency for inorganic materials. PCDTBT and PTB7 ...
Added: November 20, 2015
А.Т. П., А.Р. Тамеев, В.Г. Ш., Успехи химии 2018 Т. 87 № 10 С. 923-949
Data on the effect of electromagnetic fields on polymerization processes are analyzed and integrated. The results of
investigation of the response of polymeric systems including polymerization mixtures, polymer solutions, melts and gels to external electromagnetic fields are discussed. Mechanisms of changes in the kinetic parameters of cationic polymerization of certain monomers are considered. They are based ...
Added: July 16, 2018
Kharchenko A. A., Nadtochiy A., Mintairov S. A. et al., Nano-Structures and Nano-Objects 2021 Vol. 25 Article 100628
Electronic states in a novel type of quantum-size heterostructures referred to as InGaAs quantum welldots
(QWDs) were experimentally studied using absorption in stripe waveguides of different lengths
based on a single, double, five, and ten QWD layers. The value of the modal absorption was measured
to be 70 cm−1 and 90 cm−1 for ground-state transition and high-energy one, ...
Added: January 26, 2021
Адамов Р. Б., Мелентьев Г. А., Подоскин А. А. et al., Физика и техника полупроводников 2023 Т. 57 № 8 С. 663-673
Исследованы фото- и электролюминесценция в p-i-n-структурах с компенсированными квантовыми ямами GaAs/AlGaAs с различными профилями легирования: с пространственным разделением доноров и акцепторов (доноры локализованы в квантовых ямах, акцепторы - в барьерах) и без него (и доноры, и акцепторы локализованы в квантовых ямах). Изучались спектральные характеристики люминесценции в ближнем ИК диапазоне при гелиевых температурах. Выявлены линии излучательной ...
Added: February 5, 2024
Budkin G. V., Makhov I. S., Firsov D. A., Journal of Physics: Condensed Matter 2021 Vol. 33 No. 16 Article 165301
The flow of electric current in quantum well breaks the space inversion symmetry, which leads to the dependence of the radiation transmission on the relative orientation of current and photon wave vector, this phenomenon can be named current drag of photons. We have developed a microscopic theory of such an effect for intersubband transitions in ...
Added: October 8, 2021
Чупраков С. А., Блинов И. В., Загорский Д. Л. et al., Физика металлов и металловедение 2021 Т. 122 № 9 С. 933-939
In this work, by the method of matrix synthesis, nanowires (NPs) of various types were obtained - from pure cobalt, from an alloy of cobalt with copper and layer structures consisting of alternating layers of cobalt and copper of various thicknesses. Structural features of the arrays have been investigated by the method of nuclear magnetic ...
Added: November 12, 2021
Lounis B., Buzdin A. I., Physical Review B: Condensed Matter and Materials Physics 2022 Vol. 105 No. 2 Article L020504
We theoretically study the nonequilibrium dynamics of the order parameter of a superconducting ring inhomogeneously quenched through its transition temperature. Numerical simulations based on spectral decomposition of the time-dependent Ginzburg-Landau equation reveal that current-carrying superconducting states can be generated in the ring under certain fast local temperature quench conditions. We also show that illumination of ...
Added: December 10, 2022
Duarte E. C., Sardella E., Teixeira Saraiva T. et al., / Cornell University. Series cond-mat "arxiv.org". 2022. No. 2209.
The presence of magnetic fields and/or transport currents can cause penetration of vortices in superconductors. Their motion leads to dissipation and resistive state arises, which in turn strongly affects the performance of superconducting devices such as single-photon and single-electron detectors. Therefore, an understanding of the dissipation mechanisms in mesoscopic superconductors is not only of fundamental ...
Added: November 7, 2022
E. I. Moiseev, N. V. Kryzhanovskaya, Zubov F. I. et al., St. Petersburg Polytechnical University Journal: Physics and Mathematics 2022 Vol. 15 No. 3.2 P. 25-30
This paper is the first study of the far-field patterns of semiconductor microlasers with an active region based on In0.4Ga0.6As/GaAs quantum well-dots. A theoretical model describing the far-field radiation pattern is developed. It is shown that in the vertical direction the radiation pattern has a narrow beam divergence (the most of the power is confined ...
Added: March 15, 2023
Zhukov A., Kryzhanovskaya N., Moiseev E. et al., Физика и техника полупроводников 2020 Т. 54 № 6 С. 570-574
A model is developed that makes it possible to analytically determine the threshold current of a microdisk laser with consideration for its self-heating as a function of the ambient temperature and the microlaser diameter. It is shown that there exists a minimum microdisk diameter determined by self-heating, up to which continuous-wave lasing can be reached ...
Added: September 15, 2020
Zhukov A., Moiseev E., Nadtochiy A. et al., Письма в Журнал технической физики 2021 Т. 47 № 13 С. 28-31
The energy consumption of an uncooled microdisk quantum well-dot laser under high-frequency modulation was investigated. For a microlaser with a diameter of 20 μm, the lowest power consumption of 1.6 pJ was obtained per one bit of data transmitted using an optical signal. ...
Added: October 11, 2021
Малеев Н. А., Васильев А. П., Кузьменков А. Г. et al., Письма в Журнал технической физики 2019 Т. 45 № 21 С. 29-33
High-electron mobility transistor (HEMT) with improved breakdown characteristics has been developed. Composite InGaAs channel structure was used in combination with fully selective double recess device fabrication process. HEMTs with T-gate length of 120 nm and width 4x30 m demonstrate maximum extrinsic transconductance of 810 mS/mm, maximum drain current density of 460 mA/mm and gate-drain reverse ...
Added: December 8, 2020
Zhukov A., Kryzhanovskaya N., Moiseev E. et al., IEEE Journal of Quantum Electronics 2020 Vol. 56 No. 5 P. 1-8
We discuss the effect of self-heating on performance of injection microdisk lasers operating in continuous-wave (CW) regime at room and elevated temperature. A model is developed that allows one to obtain analytical expressions for the peak optical power limited by the thermal rollover effect, the corresponding injection current and excess temperature of the device. The ...
Added: July 30, 2020
N.A. Fominykh, F.I. Zubov, K.A. Ivanov et al., St. Petersburg Polytechnical University Journal: Physics and Mathematics 2023 Vol. 16 No. 1.2 P. 126-132
In the present work, we study the possibility of the emission output of a semiconductor microring laser through a radially coupled optical waveguide. Room temperature lasing has been achieved in continuous wave regime with the wavelength of ~1090 nm. The characteristics of microlasers with and without waveguide have been compared. We have performed a spatial ...
Added: July 3, 2023
Budkov Y., Kalikin N., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2023 Vol. 107 No. 2 Article 024503
In this paper, we present a self-consistent field theory of macroscopic forces in spatially inhomogeneous flexible chain polyelectrolyte solutions. We derive an analytical expression for a stress tensor which consists of three terms: isotropic hydrostatic stress, electrostatic (Maxwell) stress, and stress rising from conformational entropy of polymer chains—conformational stress. We apply our theory to the ...
Added: February 15, 2023
Shurakov A., Mikhailov D., Belikov I. et al., Journal of Physics: Conference Series 2020 Vol. 1695 No. 1 Article 012154
In this paper we report on the fabrication of a planar Schottky diode utilizing a Г-shaped anode suspended bridge. The bridge maintains transition between the top and bottom level planes of a 1.4 µm thick GaAs mesa. To implement the profile of a suspended bridge and inward tilt of a mesa wall adjacent to it, ...
Added: May 18, 2022
Зубов Ф. И., Максимов М. В., Kryzhanovskaya N. et al., Письма в Журнал технической физики 2021 Т. 47 № 20 С. 3-6
The output power is studied under continuous-wave operation of microdisk lasers with InGaAs/GaAs quantum well-dots hybridly integrated with a silicon substrate with the epitaxial side down using the thermocompression bonding method. Owing a decrease in the thermal resistance and suppression of self-heating, an increase in the values of currents is observed at which the power ...
Added: October 14, 2021
Shurakov A., Moltchanov D., Prikhodko A. et al., Computer Communications 2023 Vol. 201 P. 48-58
Abstract: The next step in the last mile wireless access is utilization of the terahertz (THz) frequency band spanning from 0.1 to 3 THz, specifically, its lower part (up to 300 GHz) also known as sub-THz frequencies. At these frequencies, communication systems can offer tens of consecutive gigahertz potentially allowing to further improve access rates at the ...
Added: May 11, 2023