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Direct observation of a Γ−X energy spectrum transition in narrow AlAs quantum wells
Physical Review B: Condensed Matter and Materials Physics. 2018. Vol. 97. No. 11. P. 115308-115308.
Khisameeva A. R., Shchepetilnikov A. V., Muravev V. M., Gubarev S. I., Frolov D. D., Nefyodov Y. A., Kukushkin I., Reichl C., Altshuler L., Dietsche W., Wegscheider W.
Spectra of magnetoplasma excitations have been investigated in two-dimensional electron systems in AlAs quantum wells (QWs) of different widths. The magnetoplasma spectrum has been found to change profoundly when the quantum well width becomes thinner than 5.5 nm, indicating a drastic change in the conduction electron energy spectrum. The transformation can be interpreted in terms of transition from the in-plane strongly anisotropic Xx−Xy valley occupation to the out-of-plane isotropic Xz valley in the QW plane. Strong enhancement of the cyclotron effective mass over the band value in narrow AlAs QWs is reported.
Publication based on the results of:
Ivanov S., Chernov M. Y., Solov'ev V. A. et al., Progress in Crystal Growth and Characterization of Materials 2019 Vol. 65 No. 1 P. 20-35
High-efficiency semiconductor lasers and light-emitting diodes operating in the 3–5 μm mid-infrared (mid-IR) spectral range are currently of great demand for a wide variety of applications, in particular, gas sensing, noninvasive medical tests, IR spectroscopy etc. III-V compounds with a lattice constant of about 6.1 Å are traditionally used for this spectral range. The attractive idea to fabricate such emitters on GaAs substrates by using In(Ga,Al)As ...
Added: May 31, 2021
Vinnichenko M. Y., Makhov I. S., Panevin V. Y. et al., Physica E: Low-Dimensional Systems and Nanostructures 2020 Vol. 124 Article 114301
The results of the theoretical and experimental investigations of optical response of the acceptor centers in narrow GaAs/AlGaAs quantum wells in the infrared spectral range are presented. In the theoretical part, we focused on the probabilities of the photoionization of acceptor centers taking into account the complicated valence band structure and intermixing the light and ...
Added: October 11, 2021
Vinnichenko M. Y., Fedorov A. D., Kharin N. Y. et al., Journal of Physics: Conference Series 2020 Vol. 1482 P. 1-4
Optical absorption of s- and p-polarized light was studied in GaN/AlN quantum wells in the near-infrared spectral range. An absorption peak associated with intersubband electron transitions in quantum wells was observed near a wavelength of 1.55 μm. Optoelectronic devices based on these structures can be used in fiber-optic telecommunication technologies. ...
Added: February 19, 2021
Wang Y., Rong X., Ivanov S. et al., Advanced Optical Materials 2019 Vol. 7 No. 10 P. 1-7
High‐output‐power electron‐beam (e‐beam) pumped deep ultraviolet (DUV) light sources, operating at 230–270 nm, are achieved by adjusting the well thickness of binary ultrathin GaN/AlN multiple quantum wells. These structures are fabricated on high‐quality thermally annealed AlN templates by metal‐organic chemical vapor deposition. Owing to the reduced dislocation density, large electron–hole overlap, and efficient carrier injection ...
Added: February 19, 2021
Yu. E. Lozovik, I. L. K., Pavel A. V., Physical Review B: Condensed Matter and Materials Physics 2017 Vol. 95 No. 24-5430 P. 245430-1-245430-19
We study anisotropies of the helicity modulus, excitation spectrum, sound velocity, and angle-resolved luminescence spectrum in a two-dimensional system of interacting excitons in a periodic potential. Analytical expressions for anisotropic corrections to the quantities characterizing superfluidity are obtained. We consider particularly the case of dipolar excitons in quantum wells. For GaAs/AlGaAs heterostructures as well as ...
Added: October 22, 2017
Makhov I. S., Panevin V. Y., Firsov D. A. et al., Journal of Luminescence 2019 Vol. 210 P. 352-357
The low-temperature terahertz and near-infrared photoluminescence from the near-infrared laser nanostructure with GaAs/AlGaAs quantum wells doped with shallow donors is studied under intense interband optical excitation. The optical electron transitions involving excited and ground donor states in quantum wells are revealed in terahertz and near-infrared photoluminescence spectra. Impurity assisted near-infrared stimulated emission under interband optical ...
Added: October 15, 2021
Sorokin S. V., Avdienko P. S., Sedova I. V. et al., Materials 2020 No. 13 P. 1-29
Development of molecular beam epitaxy (MBE) of two-dimensional (2D) layered materials is an inevitable step in realizing novel devices based on 2D materials and heterostructures. However, due to existence of numerous polytypes and occurrence of additional phases, the synthesis of 2D films remains a difficult task. This paper reports on MBE growth of GaSe, InSe, ...
Added: November 13, 2020
Firsov D. D., Komkov O. S., Solov’ev V. A. et al., Journal of the Optical Society of America B: Optical Physics 2019 Vol. 36 No. 4 P. 910-916
An IR photoreflectance (PR) study of two-dimensional nanoheterostructures based on InSb was performed by using Fourier-transform IR photomodulation spectroscopy. The studied structures, including InSb/Al𝑥In1−𝑥SbInSb/AlxIn1−xSb quantum wells (QWs) and type-II nanostructures with monolayer-thick InSb insertions within bulk InAs layers, were grown via molecular beam epitaxy on GaAs (001) and InAs (001) substrates, respectively. The PR spectra of the InSb/Al𝑥In1−𝑥SbInSb/AlxIn1−xSb heterostructures ...
Added: February 25, 2021
Mantsevich V. N., Rozhansky I. V., Maslova N. S. et al., Physical Review B: Condensed Matter and Materials Physics 2019 No. 99 Article 115307
We consider time-dependent processes in the optically excited hybrid system formed by a quantum well (QW) coupled to a remote spin-split correlated bound state. The spin-dependent tunneling from the QW to the bound state results in the nonequilibrium electron spin polarization in the QW. The Coulomb correlations at the bound state enhance the spin polarization ...
Added: October 21, 2021
Khisameeva A., Shchepetilnikov A., Muravev V. M. et al., Journal of Experimental and Theoretical Physics 2020 Vol. 130 No. 4 P. 594-601
The plasma oscillations in new advanced two-dimensional electron systems (2DESs) based on the heterostructures ZnO/MgZnO, AlAs/AlGaAs, and GaAs/AlGaAs are studied and compared. The relaxation times and the effective masses in samples with various electron densities in these 2DESs are found by microwave plasma spectroscopy. The specific features of the plasma oscillations in the AlAs/AlGaAs quantum ...
Added: December 10, 2020
Малевская А. В., Калюжный Н. А., Малевский Д. А. et al., Физика и техника полупроводников 2021 Т. 55 № 8 С. 699-703
Investigation of IR light emitting diodes (wavelength 850 nm) based on AlGaAs/GaAs heterostructures with multiple quantum wells InGaAs in the region generating radiation, grown by the MOCVD technique, has been carried out. Post-growth technologies for removing the growth substrate and for transfer the heterostructure on an alien carrier with an optical reflector have been developed. ...
Added: October 14, 2021
Vankov A., Бисти В. Е., Кулик Л. В. et al., Physics-Uspekhi 2015 Vol. 4 No. 58 P. 315-329
Experimental and theoretical research on neutral
excitations in a two-dimensional electron gas in a strong mag netic field is reviewed. Methods for calculating excitation en ergies in the strong-field limit for integer and noninteger filling
factors are considered. The effects of impurities and of the
nonideality of the two-dimensional system on the excitation
spectrum are examined. Experimental results that have been
obtained ...
Added: March 6, 2017
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
Minkov G. M., Rut О. Е., Sherstobitov A. A. et al., Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 101 No. 24 P. 1-7
In the present paper we study magneto-intersubband oscillations (MISO) in HgTe/Hg1−xCdxTe single quantum well with "inverted" and "normal" spectra and in conventional In1−xGaxAs/In1−yAlyAs quantum wells with normal band ordering. For all the cases when two branches of the spectrum arise due to spin-orbit splitting, the mutual arrangement of the antinodes of the Shubnikov-de Haas oscillations ...
Added: November 13, 2020
Makhov I. S., Panevin V. Y., Firsov D. A. et al., Journal of Applied Physics 2019 Vol. 126 No. 17 Article 175702
The terahertz radiation in GaAs/AlGaAs quantum wells with different types of doping was experimentally studied under interband optical excitation of nonequilibrium charge carriers. The structures doped only with donors, and the structures with a high degree of compensation of donors by acceptors were studied. The spectra of terahertz radiation associated with charge carrier transitions with ...
Added: October 15, 2021
Alexey A. Sokolik, Yurii E. Lozovik, Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 100 No. 12 P. 125409-1-125409-8
Magnetoplasmons on graphene edges in quantizing magnetic fields are investigated at different Landau-level filling factors. To find the mode frequency, the optical conductivity tensor of disordered graphene in a magnetic field is calculated in the self-consistent Born approximation, and the nonlocal electromagnetic problem is solved using the Wiener-Hopf method. Magnetoplasmon dispersion relations, velocities, and attenuation ...
Added: October 18, 2019
Sviridov D. E., Jmerik V. N., Rouvimov S. et al., Applied Physics Letters 2019 Vol. 114 No. 6 P. 1-5
Spreading resistance microscopy (SRM) was used to study nanoscale variations in electronic and structural properties of an ultrathin near-surface GaN/AlN quantum well (QW). In the SRM images of the growth surface of the GaN/AlN QW heterostructure, an inhomogeneous current contrast was detected in the form of disk-like regions of increased conductivity with the sizes in ...
Added: March 11, 2021
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
Ю.Е. Лозовик, Успехи физических наук 2018 Т. 188 № 11 С. 1203-1208
Рассматриваются новые эффекты в системах квантовых диполей: анизотропная сверхтекучесть во внешних полях, эффекты сильных корреляций и кристаллизация, фаза суперсолида. Анализируются эффекты ротонной неустойчивости, типичные для сильно коррелированных бозе-систем, но проявляющиеся в слабо взаимодействующей системе наклонных диполей. Интересными физическими реализациями рассматриваемых систем являются дипольные экситоны в связанных квантовых ямах либо в одиночной квантовой яме в сильном ...
Added: October 22, 2018
Katushkina O. A., Quemerais E., Izmodenov V.V. et al., JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS 2017 Vol. 122 No. 11 P. 10921-10937
In this work, we present for the first time the Lyman α intensities measured by Voyager 1/UVS in 2003–2014 (at 90–130 AU from the Sun). During this period Voyager 1 measured the Lyman α emission in the outer heliosphere at an almost fixed direction close to the upwind (i.e.“ toward the interstellar flow). The data show an unexpected behavior in 2003–2009: the ...
Added: January 26, 2018
Aaij R., Abdelmotteleb A. S., Abellan Beteta C. et al., The European Physical Journal C - Particles and Fields 2023 Vol. 83 Article 543
https://link.springer.com/article/10.1140/epjc/s10052-023-11673-x#Abs1 ...
Added: December 4, 2023
Ружицкая Д. Д., САМОЙЛЕНКО А. А., Иванов А. Д. et al., Optoelectronics, Instrumentation and Data Processing 2017 Vol. 54 No. 1 P. 1-8
This paper presents an algorithm for processing the transmission spectra of whisperinggallery optical microcavities for use as a nanoparticle detector. The algorithm is based on the broadening of the microcavity resonance curve during precipitation of nanoparticles on the microcavity surface. Experimental results on the detection of particles are compared with Langmuir adsorption theory. The contribution ...
Added: May 25, 2018
М. : National Instruments Russia, 2017
Содержание сборника составляют доклады с результатами оригинальных исследований и технических решений, ранее не публиковавшиеся. Мы надеемся, что предлагаемый сборник окажется полезным для специалистов, работающих в различных областях науки и техники, для широкого круга преподавателей, аспирантов и студентов ВУЗов, а также для преподавателей средних школ и технических колледжей. ...
Added: May 10, 2017
Min Namkung, Younghun K., Scientific Reports 2018 Vol. 8 No. 1 P. 16915-1-16915-18
Sequential state discrimination is a strategy for quantum state discrimination of a sender’s quantum
states when N receivers are separately located. In this report, we propose optical designs that can
perform sequential state discrimination of two coherent states. For this purpose, we consider not
only binary phase-shifting-key (BPSK) signals but also general coherent states, with arbitrary prior
probabilities. Since ...
Added: November 16, 2020