2304-9782, 2618-8686, 2405-7223
St. Petersburg Polytechnic University Journal: Physics and Mathematics
16
1.3
2023
1-193
CNF
RUS
7-13
Ioffe Institute
Bogoslovskiy
Nikita
nikitabogoslovskiy@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Petrov
Pavel
pavel.petrov@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Averkiev
Nikita
averkiev.les@mail.ioffe.ru
St. Petersburg, Russian Federation
Analytical and numerical calculations of the magnetic properties of a system of disordered spins in the Ising model
We consider a system of randomly distributed magnetic atoms and describe the exchange interaction in the Ising model with a hydrogen-like dependence of the exchange energy on distance. The density of states for such system was calculated using an advanced numerical algorithm. Furthermore, the density of states was calculated analytically. We established that finding the density of states allows calculating the dependence of magnetic susceptibility of the system on temperature and magnetic field.
10.18721/JPM.161.301
537.6
Ising model
Wang-Landau algorithm
magnetic susceptibility
https://physmath.spbstu.ru/article/2023.65.1/
CNF
RUS
14-19
Peter the Great St. Petersburg Polytechnic University
Petruk
Anton
wotgustik@yandex.ru
Peter the Great St. Petersburg Polytechnic University
Kharin
Nikita
kharin.nikita66@gmail.com
St. Petersburg, Russian Federation
Peter the Great St. Petersburg Polytechnic University
Vinnichenko
Maxim
mvin@spbstu.ru
0000-0002-0048-7512
Peter the Great St. Petersburg Polytechnic University
Norvatov
Ilya
norv2@mail.ru
St. Petersburg, Russian Federation
0000-0001-5547-9387
Alferov University
Fedorov
Vladimir
fedorov_vv@spbstu.ru
J-6066-2013
35403302800
0000-0003-3947-4994
Peter the Great St. Petersburg Polytechnic University
Firsov
Dmitry
firsov.da@spbstu.ru
Russia, 195251, St.Petersburg, Polytechnicheskaya, 29
Terahertz and stimulated near-infrared photoluminescence in bulk n-GaAs layers
The work considers the methods for increasing the intensity of low temperature terahertz luminescence in semiconductor structures with bulk epitaxial n-GaAs layers doped with silicon donors under interband optical pumping. Such an increase can be realized due to the accelerated depopulation of the ground impurity level by stimulated near-infrared radiation, which is created in the same structure. Stimulated interband emission was induced by a total internal reflection optical resonator. Samples were investigated by measuring the near-infrared photoluminescence and terahertz photoluminescence at liquid helium temperature. Impurity-assisted near-infrared spontaneous and stimulated photoluminescence and their dependences on optical pumping power was demonstrated. Impurity-assisted generation of terahertz radiation was observed in further intention to investigate the influence of near-infrared stimulated emission on it. Obtained results can be used in the development of new semiconductor terahertz emitters.
10.18721/JPM.161.302
535.3
photoluminescence
terahertz emission
gallium arsenide
impurities
stimulated radiation
https://physmath.spbstu.ru/article/2023.65.2/
CNF
RUS
20-25
Spin Optics Laboratory, St. Petersburg State University
Litvyak
Valentina
valiok.ok@gmail.com
St. Petersburg, Russian Federation
Spin Optics Laboratory, St. Petersburg State University
Cherbunin
Roman
r.cherbunin@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Soldatenkov
Fedor
St. Petersburg, Russian Federation
Ioffe Institute
Kalevich
Vladimir
kalevich@solid.ioffe.ru
St. Petersburg, Russian Federation
Spin Optics Laboratory, St. Petersburg State University
Kavokin
Kirill
kkavokin@gmail.com
St. Petersburg, Russian Federation
Study of properties of the nuclear spin system in bulk n-GaAs by warm-up spectroscopy
In this paper, we present an overview of the possibilities of nuclear spin warm-up spectroscopy method. Nuclear spin warm-up spectroscopy method is based on optical cooling and subsequent warming up of nuclear spins by oscillating magnetic field. Changes of nuclear spin temperature before and after applying of oscillating magnetic field are determined from the degree of photoluminescence polarization. This method is applied to studying the properties of the cooled nuclear spin system in bulk n-GaAs crystals. Using warm-up spectroscopy, we can investigate such thermodynamical characteristics of cooled nuclear spins as local fields, absorption coefficients and fluctuations spectral density (correlator spectrum). In particular, such experimental opportunities accompanied by theoretical interpretations allows us to investigate and control the presence of quadrupole interactions in structures. Furthermore, the nuclear spin fluctuations are reflected in the correlator spectrum, which can be recalculated from absorption coefficients. Measurements of the nuclear spin correlator are important experimental opportunity because fluctuations of nuclear spins are one of the main sources of electron spin decoherence in n-GaAs.
10.18721/JPM.161.303
535
nuclear spin system
optical cooling
absorption spectrum
nuclear spin correlator
local field
https://physmath.spbstu.ru/article/2023.65.3/
CNF
RUS
26-32
M.N. Mikheev Institute of Metal Physics, UB RAS
Perevalova
Aleksandra
domozhirova@imp.uran.ru
Ekaterinburg, Russian Federation
M.N. Mikheev Institute of Metal Physics; Ural Federal University
Fominykh
Bogdan
fominykh@imp.uran.ru
Ekaterinburg, Russian Federation
M.N. Mikheev Institute of Metal Physics, UB RAS
Chistyakov
Vasiliy
wchist@imp.uran.ru
Ekaterinburg, Russian Federation
M.N. Mikheev Institute of Metal Physics, UB RAS
Naumov
Sergey
naumov@imp.uran.ru
Ekaterinburg, Russian Federation
M.N. Mikheev Institute of Metal Physics, UB RAS
Neverov
Vladimir
neverov@imp.uran.ru
Ekaterinburg, Russian Federation
M.N. Mikheev Institute of Metal Physics; Ural Federal University
Marchenkov
Vyacheslav
Ekaterinburg, Russian Federation
Magnetoresistivity and Hall effect in Weyl semimetal WTe2
A WTe2 single crystal was grown by the chemical vapor transport method, and its electrical resistivity and galvanomagnetic properties were investigated. Single-band and twoband models were used to estimate the concentration and mobility of charge carriers in WTe2 at temperatures from 4.2 to 150 K.
10.18721/JPM.161.304
537.9
WTe2
Weyl semimetal
resistivity
magnetoresistivity
Hall effect
https://physmath.spbstu.ru/article/2023.65.4/
CNF
RUS
33-38
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS; Novosibirsk State University
Osinnykh
Igor
igor-osinnykh@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Malin
Timur
mal-tv@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Zhuravlev
Konstantin
zhur@isp.nsc.ru
Novosibirsk, Russian Federation
Determination of donor and acceptor concentrations in GaN using yellow photoluminescence band
In this paper, we present the results of the calculated and experimental dependence of photoluminescence on the excitation power density for GaN:Si layers grown by molecular beam epitaxy. A model was constructed for transitions in a compensated semiconductor upon interband generation of electron-hole pairs. It is shown that the dependence of the photoluminescence intensity on the excitation power density can be used to determine the recombination mechanism and concentrations of donors and acceptors in semiconductor.
10.18721/JPM.161.305
535.37
GaN
ammonia-MBE
photoluminescence
heterostructures
point defects
https://physmath.spbstu.ru/article/2023.65.5/
CNF
RUS
39-43
Ioffe Institute
Amelchuk
Dmitriy
mutranspet@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Mynbaeva
Marina
mgm@mail.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Smirnov
Alexander
Alex.Smirnov@mail.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Davydov
Valery
Valery.Davydov@mail.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Lebedev
Sergey
lebedev.sergey@mail.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Lebedev
Alexander
shura.lebe@mail.ioffe.ru
St. Petersburg, Russian Federation
Transfer of 3C-SiC heteroepitaxial layers grown on silicon to a 6H-SiC substrate by direct bonding technique
This paper reports on the development of direct bonding of 3C-SiC epitaxial layers grown by chemical vapor deposition on silicon substrates and 6H-SiC single crystal wafers. It has been found that the bonding temperature is a critical parameter to obtain mechanical contact between the transferred 3C-SiC layers and the 6H-SiC carrier plates. The results of structural characterization showed that the structure of epitaxial layers grown by sublimation on bonded substrates corresponds to a pure cubic phase of high quality.
10.18721/JPM.161.306
538.911
Silicon carbide
polytypes
direct splicing
templates
sublimation epitaxy
https://physmath.spbstu.ru/article/2023.65.6/
CNF
RUS
44-49
National Research University of Electronic Technology
Barsukov
Leonty
leonty.barsukov@gmail.com
Moscow, Russian Federation
0000-0003-1417-0177
National Research University of Electronic Technology
Nekrasov
Nikita
Moscow, Russian Federation
Romashkin
Alexey
romaleval@gmail.com
National Research University of Electronic Technology
Bobrinetskiy
Ivan
bobrinet@mail.ru
Moscow, Russian Federation
Levin
Denis
vkn@miee.ru
National Research University of Electronic Technology
Nevolin
Vladimir
vkn@miee.ru
Moscow, Russian Federation
Improved polymer residuals removing after the graphene transfer to enhance sensors performance
Graphene transfer using polymers as a supporting layer makes sensors with exceptional yield and few defects. It is still an issue to make scalable and versatile high-purity graphene transfer method. Current-voltage characteristic slope and hence the sensitivity of the graphenebased devices are limited by the residual polymer left after the transfer process that forms local defects and trapped states quenching charge transfer. Due to the strong interactions between polymer and graphene, residual removal remains an important problem to solve. In this work graphene on Cu foil was covered using spin-coating of poly(methyl methacrylate) (PMMA) with different molecular masses and the addition of a low volatile additive. The film obtained was transferred onto Si/SiO2 substrates. In order to remove PMMA residues multiple cleaning techniques with different solvents were used and compared to each other; new methods were developed. The quality of the purified graphene was studied by analyzing AFM, Raman, fluorescence spectroscopy data. The structure was
10.18721/JPM.161.307
[66.061.16;544.163:621.793]:681.586.72
graphene transfer
polymer removal
sensor
polymethylmethacrylate
https://physmath.spbstu.ru/article/2023.65.7/
CNF
RUS
50-54
St. Petersburg Electrotechnical University "LETI"
Kelner
Oleg
olegkelner08@gmail.com
St. Petersburg, Russian Federation
Tsatsulnikov
Andrey
andrew@beam.ioffe.ru
Nikolaev
Andrei
Aen@mail.ioffe.ru
Zavarin
Evgenii
EZavarin@mail.ioffe.ru
Curvature and bow of III-N HEMT structures during epitaxy on silicon substrates
High Electron Mobility Transistor (HEMT) heterostructures based on III-N semiconductors (nitrides of Al and Ga) have become increasingly widespread in recent years. They are used in the manufacture of microwave transistors, high- power transistors for power electronics, etc. However, mass application of such transistors requires a reduction in the cost of heterostructures due to the use of cheap substrates and an increase in the area of one substrate. Thus, substrates of single-crystal Si(111) are of great interest. They are available in diameters up to 300 mm, and the possibility of growing III-N structures has already been demonstrated for them. Nevertheless, the epitaxy of III-N HEMT structures on Si substrates is complicated due to a number of technological difficulties in the epitaxy of such structures. In this paper, the dynamics of curvature and residual bow of III-N HEMT structures were experimentally studied during epitaxy and after cooling for Si(111) substrates with a diameter of 100 mm and various thicknesses of substrates and grown semiconductor films. It has been shown that the technology developing and optimization should be carried out on thin substrates, while device structures should be grown on thick substrates. Furthermore, the mechanical stresses can be controlled accurately enough so after epitaxy the bow of the structure is minimal.
10.18721/JPM.161.308
539.3
MOVPE
HEMT
elastic strain
silicon
https://physmath.spbstu.ru/article/2023.65.8/
CNF
RUS
55-61
St. Petersburg Electrotechnical University "LETI"
Monyak
Andrey
andreimonyak@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Grebenyuk
Georgy
georgijmail@gmail.com
St. Petersburg, Russian Federation
ITMO University
Lobanova
Evgeniya
elobanova@itmo.ru
St. Petersburg, Russian Federation
Ioffe Institute
Kuzmin
Mikhail
m.kuzmin@mail.ioffe.ru
St. Petersburg, Russian Federation
Formation and magnetic properties of ultrathin cobalt silicides films on Si surface
High-resolution photoelectron spectroscopy with synchrotron radiation and magnetic linear dichroism in Co 3p core-level photoemission have been used to study the initial stages of formation and ferromagnetic ordering of Co/Si(100) and Co/Si(111) interfaces. The correlation between the phase composition, electronic structure and magnetic behavior of the interfaces has been established during Co deposition on Si surface and subsequent sample annealing. It is shown that ferromagnetic ordering has a threshold nature and arises after the deposition of 6 Å of Co in both systems. At higher Co coverages a continuous film of a Si solid solution in cobalt is found to develop. Further increase of ferromagnetic ordering of the interface is caused by the growth of pure metal film. Annealing of the samples covered with a Co film of few nm thickness leads to the gradual disappearance of the metal film and formation of four silicide phases: a metastable ferromagnetic Co3Si silicide obtained at room temperature for the first time and three stable non-magnetic cobalt silicides: Co2Si, CoSi and CoSi2. It is shown that solid-phase reactions start at ~250 °С and ~320 °С in Co/Si(100) and Co/Si(111) systems respectively.
10.18721/JPM.161.309
538.915
cobalt
magnetic properties
silicides
photoelectron spectroscopy
https://physmath.spbstu.ru/article/2023.65.9/
CNF
RUS
62-66
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Maidebura
Yan
maid@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Malin
Timur
mal-tv@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Zhuravlev
Konstantin
zhur@isp.nsc.ru
Novosibirsk, Russian Federation
Transformation kinetics of a two-dimensional GaN thin layer grown on AlN surface during ammonia flow cycling
In this work the transformation kinetics of GaN pseudomorphic layer and the lattice constant evolution of 2D GaN “frozen” layer under sequential switching off/on of ammonia flow at a growth temperature of 740 °C were investigated by reflection high energy electron diffraction method (RHEED). It was shown by the Bragg spot kinetics intensity of GaN layer that when ammonia flow is turned off, the intensity of Bragg spot reaches saturation and does not change during the exposure time in vacuum, while the maximum achieved intensity decreases when ammonia flow is turned off/on sequentially. Hence there is practically no effect of thermal decomposition on the change in the morphology of the GaN layer. It was found experimentally that the GaN layer formed with each cycle of 2D "frozen" is partially relaxed, which is explained within the Mariette equilibrium model. Thus, relaxation of elastic energy of 2D "frozen" GaN layer is due to the fact that some amount of 3D islands remains on the surface and the decrease of elastic energy value is caused by losses for islands faceting maintenance.
10.18721/JPM.161.310
539.23
GaN quantum dots
surface morphology
2D-3D transition
surface processes
ammonia MBE
RHEED
https://physmath.spbstu.ru/article/2023.65.10/
CNF
RUS
67-72
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Strygin
Ivan
vanya-91@yandex.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Bykov
Alexey
bykov@isp.nsc.ru
Novosibirsk, Russian Federation
Magneto-intersuband resistance oscillations in a one-dimensional lateral superlattice
This paper presents the results of a study of magneto-intersubband resistance oscillations in a one-dimensional lateral superlattice fabricated on the basis of a single GaAs quantum well with two filled energy subbands. A strong modification of magneto-intersubband oscillations both in amplitude and in phase has been observed. The obtained experimental data are explained by the role of Van Hove singularities in resonant intersubband transitions.
10.18721/JPM.161.311
538.9
magneto-intersubband oscillations
lateral superlattice
https://physmath.spbstu.ru/article/2023.65.11/
CNF
RUS
73-78
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Timofeev
Vyacheslav
Vyacheslav.t@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Mashanov
Vladimir
mash@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Nikiforov
Alexander
nikif@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Skvortsov
Ilya
i.skvortsov@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Bloshkin
Alexey
bloshkin@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Loshkarev
Ivan
idl@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Azarov
Ivan
azarov_ivan@mail.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Kirienko
Viktor
victor@isp.nsc.ru
Novosibirsk, Russian Federation
Investigation of infrared photoresponse from structure with GeSiSn/Si multiple quantum wells
The current-voltage (I-V) characteristics and spectral dependences of the photocurrent of p-i-n structures, including GeSiSn/Si multiple quantum wells (MQWs) with the Sn content up to 15%, are studied. It is shown that the increase in the Sn content from 4.5 to 13% leads to a gradual increase in the dark current density from 6×10−6 A/cm2 to 5×10−5 A/cm2 at the reverse bias of 1 V. The further rise in the Sn content to 15% results in the increase of the dark current density to 5×10−4 A/cm2, which is an order of magnitude lower than the known values for GeSn-based photodiodes. The shift of the cutoff wavelength of the photoresponse with the Sn content increase in heterostructures is demonstrated. The photoresponse spectrum of the detector extends up to wavelengths of larger than 2 μm at the Sn content of more than 10%.
10.18721/JPM.161.312
621.383.52
multiple quantum well
band diagram
dark current
photocurrent
https://physmath.spbstu.ru/article/2023.65.12/
CNF
RUS
79-84
Spin Optics Laboratory, St. Petersburg State University
Sultanov
Oleg
oleg123pl@gmail.com
St. Petersburg, Russian Federation
Spin Optics Laboratory, St. Petersburg State University
Yugova
Irina
i.yugova@spbu.ru
St. Petersburg, Russian Federation
Spin Optics Laboratory, St. Petersburg State University
Mikhailov
Andrey
mikhailovav@yandex.ru
St. Petersburg, Russian Federation
Modeling of coherent dynamics of excitons in a GaAs quantum well in the pump-probe experiment
We investigated polarization-dependent quantum beats of excitons with light and heavy holes observed in the pump-probe experiment. Oscillations in the energy of exciton resonances have been experimentally observed upon simultaneous excitation of exciton levels. To explain this effect, a theoretical model was formulated based on the consideration of a five-level scheme with the inclusion of nonlinearity in the form of an exchange exciton-exciton interaction. It has been found that the shift of energy resonances can be described only if the exciton-exciton exchange interaction is taken into account. The results of theoretical calculations of the coherent dynamics of excitons in this model are in agreement with the experimental data.
10.18721/JPM.161.313
535.3
quantum well
excitons
coherent dynamics
computer modeling
https://physmath.spbstu.ru/article/2023.65.13/
CNF
RUS
85-89
Talnishnikh
N.A.
Nadya.FEL@mail.ru
Ivanov
Anton
a-e-ivano-v@yandex.ru
0000-0003-4457-8149
Ioffe Institute
Shabunina
Evgeniia
St. Petersburg, Russian Federation
Shmidt
Natalia
Peculiarities of low frequency noise and non-radiative recombination in AlGaN QWs emitting at 280 nm
A prominent source of charge carrier losses due to non-radiative recombination in AlGaN QWs, caused by the presence of charged centers localized at disordered hetero interfaces, has been experimentally revealed. It was found out that the spectral density of current low-frequency noise, which carries integral information about single defects and a defect system, is an order of magnitude higher in AlGaN QWs than in effective blue InGaN/GaN QWs. Thus, non-radiative recombination losses are still the source responsible for the low quantum efficiency of ultraviolet LEDs.
10.18721/JPM.161.314
621.382.2
AlGaN/GaN
LEDs
UV LEDs
EQE
low-frequency noise
non-radiative recombination
QWs
https://physmath.spbstu.ru/article/2023.65.14/
CNF
RUS
90-95
St. Petersburg Electrotechnical University "LETI"
Kiianitsyn
Sergey
serg-kianitsyn@mail.ru
St. Petersburg, Russian Federation
0000-0002-4894-6503
Alferov University
Baranov
Artem I.
baranov_art@spbau.ru
St. Petersburg, Russian Federation
0000-0002-0061-6687
Alferov University
Uvarov
Alexander
lumenlight@mail.ru
0000-0002-3503-7458
St. Petersburg Electrotechnical University "LETI"
Maksimova
Alina A.
deer.blackgreen@yandex.ru
0000-0001-6869-1213
Alferov University
Vyacheslavova
Ekaterina
cate.viacheslavova@yandex.ru
0000-0002-7632-3194
Alferov University
Gudovskikh
Alexander
gudovskikh@spbau.ru
Study of photoconvertion heterojunction n-GaP/p-Si obtained by PE-ALD
Plasma-enhanced atomic layer deposition is an attractive method for producing n-GaP layers at low temperatures on p-Si wafers for further photovoltaic application of n-GaP/p-Si heterostructures. In this study, we explore the influence of growth conditions on the electrophysical quality of thin n-GaP layers. It was established from admittance spectroscopy and current-voltage characteristics that the activation energy of conductivity in GaP decreases from 0.08 eV to 0.04 eV, with an increase in phosphine flow during the phosphorous step, and a subsequent drop to an extremely low value (< 0.02 eV) when additional flow of silane was added. This leads to extreme improve photovoltaic performance of the ITO/n-GaP/p-Si sample due to suppression of inflection on the I–V curve leading to an increase in the short-circuit current and the fill factor. Fruthermore, a deep level with the activation energies ranging from 0.50 to 0.55 eV and the capture cross-section σT = (1–10)·10–16 cm2 was detected in all layers.
10.18721/JPM.161.315
621.383
solar cell
GaP/Si heterojunction
admittance spectroscopy
atomic-layer deposition
https://physmath.spbstu.ru/article/2023.65.15/
CNF
RUS
96-100
0000-0002-2158-9489
Submicron Heterostructures for Microelectronics Research and Engineering Center of the RAS
Leshchenko
Egor
leshchenko.spb@gmail.com
St. Petersburg, Russian Federation
0000-0003-2088-7158
St. Petersburg State University
Dubrovskii
Vladimir
St. Petersburg, Russian Federation
Modeling of interfacial profile of axial GaAs/ AlAs nanowire heterostructures
We describe the formation of axial GaAs/AlAs heterostructured nanowires grown via the vapor-liquid-solid method. The calculations are based on the combination of mass balance of atoms in the droplet and the nucleation-limited composition of ternary AlxGa1-xAs nanowires. We examine the influence of growth temperature, atomic Al flux and the Au concentration in the liquid on the interfacial abruptness. In particular, we compare the compositional profiles of heterostructures in Au-catalyzed and self-catalyzed nanowires. The obtained results might be useful for growth of GaAs/AlAs heterostructured nanowires.
10.18721/JPM.161.316
538.975
interfacial profile
axial heterostructures
AlGaAs
nanowires
modeling
https://physmath.spbstu.ru/article/2023.65.16/
CNF
RUS
101-107
0000-0003-4123-4375
Peter the Great St. Petersburg Polytechnic University
Ustimenko
Ratmir
ustimenko_rv@spbstu.ru
St. Petersburg, Russian Federation
Peter the Great St. Petersburg Polytechnic University
Vinnichenko
Maxim
mvin@spbstu.ru
Peter the Great St. Petersburg Polytechnic University
Karaulov
Danila
karaulov.da@edu.spbstu.ru
St. Petersburg, Russian Federation
J-6066-2013
35403302800
0000-0003-3947-4994
Peter the Great St. Petersburg Polytechnic University
Firsov
Dmitry
firsov.da@spbstu.ru
Russia, 195251, St.Petersburg, Polytechnicheskaya, 29
0000-0001-5547-9387
Alferov University
Fedorov
Vladimir
fedorov_vv@spbstu.ru
0000-0002-8661-4083
Alferov University
Mozharov
Alexey
mozharov@spbau.ru
St. Petersburg, Russian Federation
0000-0002-1571-209X
ITMO University
Kirilenko
Demid
demid.kirilenko@mail.ioffe.ru
St. Petersburg, Russian Federation
0000-0001-9792-045X
Peter the Great St. Petersburg Polytechnic University
Mukhin
Ivan
muhin_is@spbstu.ru
Interband photoluminescence of InAs(P)/Si nanowires
Semiconductor nanowires have a number of advantages over thin films and bulk analogues, which allow them to be used to develop efficient detectors and light sources. In this work, photoluminescence spectra of pure InAs and core-shell InAs/CaF2 and InAs/InP nanowires on silicon were studied in the near infrared spectral range at various levels of optical pumping and at different temperatures using a vacuum Fourier spectrometer operating in a step-scan mode. The observed peaks in the photoluminescence spectra correspond to interband transitions in InAs of sphalerite and wurtzite phases. The photoluminescence spectra of CaF2-coated InAs nanowires demonstrated that surface passivation with CaF2 does not change the spectral features. It was shown that the absolute value of photoluminescence intensity of InAs-core/InP-shell nanowires exceeds the intensity of pure InAs nanowires. It means that surface passivation can reduce an effect of surface states in nanowires on their optical properties.
10.18721/ JPM.161.317
535.3
nanowires
passivation
photoluminescence
core/shell nanowires
https://physmath.spbstu.ru/article/2023.65.17/
CNF
RUS
108-111
Moscow Institute of Physics and Technology (MIPT)
Burdanova
Maria
burdanova.mg@mipt.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Chiglintsev
Emil
chiglintsev.eo@phystech.edu
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Paukov
Maksim
Paukov.mi@phystech.edu
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Mishra
Prabhash
prabhash786@gmail.com
Moscow, Russian Federation
MIREA - Russian Technological University
Brekhov
Kirill
brekhov_ka@mail.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Arsenin
Aleksey
Arsenin.av@mipt.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Volkov
Valentyn
vsv.mipt@gmail.com
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Chernov
Alexander
a.chernov@rqc.ru
Moscow, Russian Federation
High-field terahertz time-domain spectroscopy of single-walled carbon nanotubes
We experimentally demonstrated the high-field THz response of Single-Walled Carbon Nanotubes (SWCNT) in the broad frequency range from 0.2 to 2.0 THz. To investigate the impact of nanomaterial geometry on the absorption of THz radiation, two kinds of SWCNT films with different diameters and lengths were fabricated. The measured conductivity shows the change that can be attributed to the change of the Drude term of conductivity. This increase in conductivity at lower frequency was described either as the increase in the number or decrease in effective masses of free charge carriers different for two samples. Our study suggests that the conductivity of the SWNTs in strong THz fields is enhanced by inducing strong nonlinear electron dynamics as a result of several competing processes. Our findings can be used to predict the behavior of CNT devices (modulators, polarizes, lenses, etc.) in the THz high-field.
10.18721/JPM.161.318
543.42
carbon nanotubes
high-field THz spectroscopy
THz spectroscopy
https://physmath.spbstu.ru/article/2023.65.18/
CNF
RUS
112-116
Ioffe Institute
Afanasev
Kirill
gruzaa01@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Lebedev
Dmitrii
lebedev_84@mail.ru
St. Petersburg, Russian Federation
Ioffe Institute
Vlasov
Alexei
vlasov@scell.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Balunov
Petr
balunov239@yandex.ru
St. Petersburg, Russian Federation
Ioffe Institute
Mintairov
Alexander
amintairov@mail.ioffe.ru
St. Petersburg, Russian Federation
Suppression of molecular anyon states in the magneto-photoluminescence spectra of InP/GaInP2 quantum dots at a temperature of 30 K
We used the photoluminescence spectra of a single InP/GaInP2 quantum dot with a Wigner-Seitz radius of about 3.4, doped with 4 electrons, to measure the magnetic field dispersion of single quantum states in a range between 0 and 10 T at 30 K. The measurements show the formation of a molecular structure at high temperature and its transition to a puddle-like structure with a decrease of localization size from 110 nm to 70 nm. Fock-Darwin spectrum fitting shows a decrease in the cyclotron frequency and magnetic field shift, that are interpreted as the formation of an anyon structure in a QD with fractional charge 1/5, 2/3, 1/2 and a built-in magnetic field of −3T.
10.18721/JPM.161.319
538.915
single quantum dots
anyon
Wigner localization
Fock-Darwin spectrum
magneto-photoluminescence
https://physmath.spbstu.ru/article/2023.65.19/
CNF
RUS
117-123
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Sarypov
Daniil
d.sarypov@g.nsu.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Pokhabov
Dmitriy A.
pokhabov@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Pogosov
Arthur
pogosov@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Zhdanov
Evgeniy
zhdanov@isp.nsc.ru
Novosibirsk, Russian Federation
Rzhanov Institute of Semiconductor Physics Siberian Branch of RAS
Bakarov
Askhat
Novosibirsk, Russian Federation
Electrically controlled switching between spatially separated conducting channels in a quantum point contact
We demonstrate transverse magnetic focusing of electrons in semiconductor devices consisting of two trenched-type quantum point contacts (QPC) acting as an injector and a detector. The peak in the detector voltage, corresponding to the penetration of injected electrons into the detector, is observed. Applying the voltage difference between injector side gates is found to cause an abrupt shift of the peak position on the magnetic field scale. This shift can be explained by switching between spatially separated channels inside the multi-well potential formed inside a QPC-injector.
10.18721/JPM.161.320
538.9
ballistic electron transport
quantum point contact
multichannelity
multi-well potential
transverse magnetic focusing
https://physmath.spbstu.ru/article/2023.65.20/
CNF
RUS
124-127
Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), RAS
Moiseenko
Ilia
quikc@yandex.ru
Saratov, Russian Federation
Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), RAS
Fateev
Denis
fateevdv@yandex.ru
Saratov, Russian Federation
Influence of DC current direction in graphene on dispersion and amplification of plasmons in graphene
We investigate dispersion and amplification of plasmon eigen modes in graphene with a direct electric current (DC-current) directed arbitrarily relative to the direction of plasmon propagation. Graphene is described by tensor conductivity obtained in the hydrodynamic approximation. We detected the possibility of amplification of plasmons in graphene in a certain range of DC current directions at terahertz frequencies. The most effective amplification is achieved when the drift of charge carriers and plasmons propagate co-directionally. This is due to the most effective interaction of DC current with the electric field of plasmons.
10.18721/JPM.161.321
537.86
hydrodynamic graphene
terahertz radiation
surface plasmon amplification
https://physmath.spbstu.ru/article/2023.65.21/
CNF
RUS
128-134
Ioffe Institute
Bolshakov
Vladimir
lion080895@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Ermina
Anna
annaermina97@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Prigoda
Kristina
kristina_prigoda@mail.ru
St. Petersburg, Russian Federation
Peter the Great St. Petersburg Polytechnic University
Maximov
Maxim
maximspbstu@mail.ru
St. Petersburg, Russian Federation
Ioffe Institute
Tolmachev
Vladimir
tva@mail.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Zharova
Yuliya
piliouguina@mail.ioffe.ru
St. Petersburg, Russian Federation
Study of composite structure based on Ag and SiNWs
In this study, we propose a method for creating a composite structure consisting of an array of vertical silicon nanowires (SiNWs) and silver nanoparticles (AgNPs). To obtain SiNWs, the process of two-stage metal-assisted chemical etching of c-Si was used, and to obtain a uniform distribution of AgNPs in the SiNW array over their entire height, the atomic layer deposition method was used. The structural and optical characteristics of the AgNPs/SiNWs were studied by nondestructive spectroscopic ellipsometry and scanning electron microscopy before and after the preparation of the composite structure. The thickness (from 2.7 to 7.8 nm) of AgNPs layers deposited on a c-Si substrate and their complex dielectric functions were determined within the framework of the Drude-Lorentz model, on which resonance peaks of localized and bulk plasmons are observed. For an array of SiNWs, using a multilayer model and the effective Bruggeman medium approximation, the height of sublayers and the Si fraction in them, as well as the Ag fraction in the Ag/SiNWs composite structure, are determined. The c-Si:Ag composite structure has been characterized by comparing the calculation and experiment. The optical properties of Ag/SiNWs structures with complex spatial geometry are modeled using the COMSOL Multiphysics software package. The expected localization of
the electric field is observed on the surface and near the AgNP as a result of the excitation of localized plasmon resonance. The calculated enhanced factor reached 1010, which suggests that composite AgNPs/SiNWs structure is promising to use as a substrate for surface-enhanced Raman scattering.
10.18721/JPM.161.322
538.975
Ag nanoparticles
Si nanowires
atomic layer deposition
metal-assisted chemical Etching (MACE)
spectroscopic ellipsometry
localized plasmon resonance
https://physmath.spbstu.ru/article/2023.65.22/
CNF
RUS
135-139
Prokhorov General Physics Institute, RAS
Romshin
Alexey
alex_31r@mail.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Gritsienko
Alexander
grits_alex@rambler.ru
Moscow, Russian Federation
Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), RAS
Ilin
Alexey
alexey.ilin@phystech.edu
Saratov, Russian Federation
Vereshchagin Institute of High Pressure Physics RAS
Bagramov
Rustem
bagramov@mail.ru
Moscow, Russian Federation
Vereshchagin Institute of High Pressure Physics RAS
Filonenko
Vladimir
vpfil@mail.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Vitukhnovsky
Alexey
alexei@sci.lebedev.ru
Moscow, Russian Federation
Prokhorov General Physics Institute, RAS
Vlasov
Igor
vlasov@nsc.gpi.ru
Moscow, Russian Federation
Enhancing single-photon emission of silicon-vacancy centers in nanodiamonds by a gold film
In this work, the single-photon emission of SiV-centers in HPHT-nanodiamonds positioned on the surface of silicon plate and gold film was investigated. Fluorescence spectra, saturation curves and fluorescence decay curves were measured for a number of SiV-emitters. A reduction in the fluorescence lifetime by ~20%, as well as a spectral shift and a decrease in the width of the zero-phonon line of SiV fluorescence were observed for most emitters. Analysis of
the saturation curves revealed an increase in the emission rates by an average of 3 times, and up to 13 times for some particles. The wide variation is primarily associated with the orientation of the dipole moment of the SiV centers and the size of diamond particles, which are the key parameters regulating the coupling of the emitter with surface plasmons in the gold film.
10.18721/JPM.161.323
535-4
nanodiamonds
color centers
single photon
fluorescence
plasmonics
https://physmath.spbstu.ru/article/2023.65.23/
CNF
RUS
140-145
Alferov University
Kharchenko
Anton
antoshkerrr@gmail.com
St. Petersburg, Russian Federation
Nadtochiy
Alexey
al.nadtochy@mail.ioffe.ru
Mintairov
Sergei
mintairov@scell.ioffe.ru
Kalyuzhniy
Nikolai
nickk@mail.ioffe.ru
Maximov
Mikhail
maximov @beam.ioffe.ru
Polarimetry of waveguiding heterostructures with quantum well-dots
The effect of the waveguide and the quantum well-dot active region on polarization of transmitted light in laser-like heterostructures was studied with the polarimetry technique. The waveguide structures with quantum well-dots were demonstrated to have almost no effect on the transmitted radiation polarization when it is parallel or perpendicular to active region layers. However, in the case of intermediate angle of linear polarization, the transmitted radiation represents a mixture of elliptically polarized and unpolarized light. The largest degree of depolarization found was at 45° of linear polarization angle of the input radiation. Depolarization was found to increase with decreasing of number of QWD layers and reaches 23% for a single layer.
10.18721/JPM.161.324
538.958
optical polarization
Stokes parameters
quantum well-dots
waveguiding heterostructures
https://physmath.spbstu.ru/article/2023.65.24/
CNF
RUS
146-150
Moscow Institute of Physics and Technology (MIPT)
Paukov
Maksim
Paukov.mi@phystech.edu
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Starchenko
Vladimir
starchenko.vv@phystech.edu
Moscow, Russian Federation
Skolko Institute of Science and Technology
Krasnikov
Dmitriy
krasnikovdmitry@gmail.com
Moscow, Russian Federation
Zhukov
Sergey
zhukov.ss@mipt.ru
Moscow Institute of Physics and Technology (MIPT)
Gorshunov
Boris
bpgorshunov@gmail.com
Moscow, Russian Federation
Skolko Institute of Science and Technology
Nasibulin
Albert
nasibulin@skoltech.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Arsenin
Aleksey
Arsenin.av@mipt.ru
Moscow, Russian Federation
Moscow Institute of Physics and Technology (MIPT)
Volkov
Valentyn
vsv.mipt@gmail.com
Moscow, Russian Federation
Stretchable carbon-nanotube films as opto-mechanically controllable modulators of terahertz radiation
This study considers the optical modulation parameters of THz radiation generated via optical-pump terahertz probe spectroscopy, passing through thin films of single-walled carbon nanotubes (SWCNT), attached onto the stretchable substrate. We investigated the dependence of photoconductivity of the stretched film on the elongation and orientation of its direction towards THz beam polarization. We interpreted the changes observed, establishing
the key factors affecting the photoconductive pathways. The obtained modulators were characterized practically: the wide range of modulation depths (MD) (up to 100%) and fast lifetimes of photoinduced charge carriers (5 ps) were marked. This research guides the way to construct the devices of switchable optoelectronics, which are of a perspective in the THz data transfer systems.
10.18721/JPM.161.325
538.9
terahertz modulator
carbon nanotubes
THz-TDS
optical-pump terahertz probe spectroscopy
ultrafast devices
https://physmath.spbstu.ru/article/2023.65.25/
CNF
RUS
151-156
Lobachevsky State University of Nizhni Novgorod
Ryabova
Margarita
rmargo01@mail.ru
Nizhni Novgorod, Russian Federation
Lobachevsky State University of Nizhni Novgorod
Filatov
Dmitrii
dmitry_filatov@inbox.ru
Nizhni Novgorod, Russian Federation
Lobachevsky State University of Nizhni Novgorod
Novikov
Alexey
gomerbc1995@gmail.com
Nizhni Novgorod, Russian Federation
Lobachevsky State University of Nizhni Novgorod
Shenina
Maria
cyrix@bk.ru
Nizhni Novgorod, Russian Federation
Lobachevsky State University of Nizhni Novgorod
Antonov
Ivan
ivant@nifti.unn.ru
Nizhni Novgorod, Russian Federation
Lobachevsky State University of Nizhni Novgorod
Kotomina
Valentina
kotominav@list.ru
Nizhni Novgorod, Russian Federation
Lobachevsky State University of Nizhni Novgorod
Liskin
Dmitrii
dmitry_liskin@mail.ru
Nizhni Novgorod, Russian Federation
Ershov
Alexey
ershov@phys.unn.ru
Lobachevsky State University of Nizhni Novgorod
Gorshkov
Oleg
gorshkov@nifti.unn.ru
Nizhni Novgorod, Russian Federation
Optically controlled memristor based on ZrO2(Y) film with Au nanoparticles
We report on the fabrication and investigation of prototype optically controlled memristors based on ZrO2(Y) (12% mol. Y2O3) with Au nanoparticles (NPs) of 2–3 nm in diameter formed by layer-by-layer magnetron deposition of ZrO2(Y)/Au/ZrO2(Y) stacks followed by annealing. The upper contacts of the memristor stacks were made from indium-tin oxide (ITO) to provide the access of photoexcitation to the active Au NP array. The crosspoint memristor devices with the active region sizes of 2020 μm2 were defined by standard photolithography with wet etching. A shift of the switching voltages from the high resistance state into the low resistance one and back has been observed under the photoexcitation at the wavelength of 650 nm corresponding to the collective plasmon resonance in the dense Au NP array. The effect was related to the charging of the Au NPs due to the internal photoemission of the electrons from the Au NPs into the ZrO2(Y) matrix enhanced by the plasmon resonance. It leads to the redistribution of the electric field near the Au NPs that, in turn, stimulates the switching process. The optically-controlled memristors investigated are promising for application in various fields of memristive photonics.
10.18721/JPM.161.326
535.3
memristor
Au nanoparticles
plasmon resonance
https://physmath.spbstu.ru/article/2023.65.26/
CNF
RUS
157-162
National Research University “Higher School of Economics”
Karaborchev
Aleksei
alex_karaborchev@mail.ru
St. Petersburg, Russian Federation
National Research University ‘Higher School of Economics”
Makhov
Ivan
imahov@hse.ru
Maximov
Mikhail
maximov @beam.ioffe.ru
Kryzhanovskaya Natalia V.
Natalia
nkryzhanovskaya@hse.ru
35379962200
Ioffe Physical Technical Institute of the Russian Academy of Sciences
Zhukov
Alexey
zhukov@beam.ioffe.ru
Russia, 194021, St.Petersburg, Polytechnicheskaya 26
Multi-state lasing in microdisk lasers with InAs/GaAs quantum dots
The paper reports on the implementation of two-level lasing in injection microlasers with self-organized InAs/GaAs quantum dots. Emission bands related to the radiative electron-hole recombination involving ground and several excited states of quantum dots are observed in the spontaneous electroluminescence spectra. We investigated two-level lasing via the ground and first excited states of quantum dots in microdisks with different cavity diameters.
A decrease in the threshold currents is observed for both ground and first excited transitions in quantum dots with a decrease in the microdisk diameter. The temperature dependences of the threshold current density for microdisks of various diameters suggest that two-level lasing is observed up to 90–100 °C.
10.18721/JPM.161.327
538.958, 535.37
two-state lasing
quantum dots
microdisks
electroluminescence
https://physmath.spbstu.ru/article/2023.65.27/
CNF
RUS
163-169
Ioffe Institute
Kovach
Yakov
yakovachyakov@gmail.com
St. Petersburg, Russian Federation
Ioffe Institute
Blokhin
Sergei
blokh@mail.ioffe.ru
St. Petersburg, Russian Federation
Babichev
Andrei
scientific.ocean@gmail.com.
Ioffe Institute
Bobrov
Mikhail
bobrov.mikh@gmail.com
St. Petersburg, Russian Federation
0000-0002-3449-8711
Ioffe Institute
Blokhin
Aleksey
Aleksey.Blokhin@mail.ioffe.ru
St. Petersburg, Russian Federation
0000-0002-9448-2471
Connector Optics LLC
Gladyshev
Andrey
andrey.gladyshev@connector-optics.com
St. Petersburg, Russian Federation
ITMO University
Novikov
Innokenty
innokenty.novikov@itmo.ru
St. Petersburg, Russian Federation
ITMO University
Karachinsky
Leonid
lkarachinsky@itmo.ru
St. Petersburg, Russian Federation
JSC OKB-Planeta
Voropaev
Kirill
kirill.voropaev@novsu.ru
V. Novgorod, Russian Federation
0000-0002-0789-4241
Alferov University
Egorov
Anton
anton.egorov@connector-optics.com
St. Petersburg, Russian Federation
1.55 μm optical-fiber transmitter based on vertical cavity surface emitting laser obtained by wafer fusion technology
In this work, the static and dynamic characteristics of a 1.55 μm optical-fiber transmitter based on wafer-fused VCSEL were studied. The device demonstrated single-mode lasing with SMSR >30 dB over a wide range of currents, and the maximum optical output power at the fiber end more than 2.5 mW. The measured –3 dB modulation bandwidth exceeded 11 GHz, and the maximum bit rate achieved was 25 Gbps. Analysis of the lasing spectra under different amplitude modulations was carried out. Positive chirping (spectra broadening) and fiber chromatic dispersion were limiting factors for the data transmission over SMF-28 fiber.
10.18721/JPM.161.328
621.373.826
VCSEL
optical-fiber transmitter
chirping
wafer-fusion
data transmission
https://physmath.spbstu.ru/article/2023.65.28/
CNF
RUS
170-175
Ivanov
Anton
a-e-ivano-v@yandex.ru
Talnishnikh
N.A.
Nadya.FEL@mail.ru
Submicron Heterostructures for Microelectronics Research and Engineering Center of the RAS
Chernyakov
Anton
chernyakov.anton@yandex.ru
Russia, 194021, St.Petersburg, Polytechnicheskaya, 26
Submicron Heterostructures for Microelectronics Research and Engineering Center of the RAS
Zakgeim
Alexander
zakgeim@mail.ioffe.ru
Russia, 194021, St.Petersburg, Polytechnicheskaya, 26
Current and temperature dependences of optical characteristics of powerful deep UV AlGaN LED (λ = 270 nm)
The main goal of this work was to study the energy characteristics of deep ultraviolet light-emitting diodes and to establish the physical reasons for the limiting of output optical power and conversion efficiency of such devices. The voltage-current, light-current and spectral characteristics of the AlGaN multiquantum wells flip-chip light-emitting diodes emitting at a wavelength of 270 nm were experimentally studied in a wide range of operating current densities of 0.01–2.5 kA/cm2 and ambient temperatures of 200–350 K. Using the ABC-model, it was found that at a relatively high internal quantum efficiency of radiation of ~70–90% and a quite acceptable value of series resistance of ~1 Ω. The main factor (key obstacle) limiting the energy possibilities of devices is low light extraction efficiency. The latter is due to the strong absorption of the generated light in the chip volume and on the contacts, as well as total internal reflection on the AlGaN/sapphire and sapphire/air interfaces.
10.18721/JPM.161.329
628.9.038
AlGaN
deep UV
light-emitting diodes
internal quantum efficiency
light-extraction efficiency
ABC-model
light-current characteristic
https://physmath.spbstu.ru/article/2023.65.29/
CNF
RUS
176-181
0000-0001-6869-1213
Alferov University
Vyacheslavova
Ekaterina
cate.viacheslavova@yandex.ru
0000-0002-0061-6687
Alferov University
Uvarov
Alexander
lumenlight@mail.ru
0000-0002-3503-7458
St. Petersburg Electrotechnical University "LETI"
Maksimova
Alina A.
deer.blackgreen@yandex.ru
0000-0002-4894-6503
Alferov University
Baranov
Artem I.
baranov_art@spbau.ru
St. Petersburg, Russian Federation
0000-0002-7632-3194
Alferov University
Gudovskikh
Alexander
gudovskikh@spbau.ru
Formation of radial amorphous hydrogenated silicon p-i-n solar cells on silicon nanowire arrays toward flexible photovoltaics
The influence of silicon nanowire (SiNWs) geometry on the efficiency of radial p-i-n junction solar cell is studied using experimental measurements. Solar cells based on vertically aligned structures with the SiNWs less than 10 μm in height are practically on par with the planar element in terms of the open-circuit voltage, exceeding it in terms of short-circuit current density by up to 1.5 times (3.9–4.9 mA/cm2). The increase in the short-circuit current density is associated with the broadening of the quantum efficiency (EQE) spectrum. There is a significant broadening of the EQE boundary to the short-wavelength region with a decrease in the diameter of the SiNWs (from 1.8 to 0.7 μm). A decrease in the open-circuit voltage and a decrease in the absolute value of EQE are observed for structures with SiNWs more than 10 μm in height.
10.18721/JPM.161.330
621.383.51
radial p-i-n junction
amorphous silicon
silicon nanowires
solar cell
https://physmath.spbstu.ru/article/2023.65.30/
CNF
RUS
182-187
Ioffe Institute
Semenov
Aleksey
semenov@beam.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Nechaev
Dmitrii
nechayev@mail.ioffe.ru
St. Petersburg, Russian Federation
Ioffe Institute
Berezina
Daria
dariya.burenina@mail.ioffe.ru
St. Petersburg, Russian Federation
Guseva
Yulia
Guseva.Julia@mail.ioffe.ru
Kulagina
Marina M.
Marina.Kulagina@mail.ioffe.ru
Ioffe Institute
Smirnova
Irina
irina@quantum.ioffe.ru
St. Petersburg, Russian Federation
Zadiranov
Yuri
Ioffe Institute
Troshkov
Sergei
S.Troshkov@mail.ioffe.ru
St. Petersburg, Russian Federation
Shmidt
Natalia
Formation of ohmic contacts to n-AlxGa1-xN:Si layers with a high aluminum content
The paper describes the results of optimizing rapid thermal annealing (RTA) of ohmic contacts to AlGaN:Si layers with a high aluminum content (70 mol%) and various electron concentration. The contact characteristics were measured using the transmission line method (TLM). It has been found that for highly doped Al0.7Ga0.3N:Si layers (>1018cm−3), the RTA annealing of Ti(25nm)/Al(80nm)/Ti/Au contact at a temperature 900 °C for 60 s makes it possible to obtain the minimum contact resistance of 8 Ω×mm and specific contact resistivity of 9×10−4 Ω·cm2 with high uniformity over the surface of a 2-inch substrate. For lightly doped Al0.7Ga0.3N:Si layers (
10.18721/ JPM.161.331
621.383
AlGaN solid alloys
contact resistance
transmission line method
rapid thermal annealing
ohmic contacts
https://physmath.spbstu.ru/article/2023.65.31/
CNF
RUS
188-191
ITMO University
Kutuzova
Aleksandra
a.kutuzova@metalab.ifmo.ru
St. Petersburg, Russian Federation
ITMO University
Rybin
Mikhail
m.rybin@metalab.ifmo.ru
St. Petersburg, Russian Federation
Switchable supercavity modes in metasurfaces based on phase change materials
The paper considers a switchable high-index metasurface made of Ge2Sb2Te5 compound. Varying the lattice spacing between the scatterers, we examined the fundamental dipole-type mode defining the metamaterial properties. At a certain lattice spacing, the structure has the reliable resonance in spectrum for the case of crystalline phase of Ge2Sb2Te5, while the resonance in the case of amorphous phase degrades completely.
10.18721/JPM.161.332
3937
bound states in the continuum (BIC)
supercavity modes
metasurface
GST
https://physmath.spbstu.ru/article/2023.65.32/