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Coherence-decoherence transition in a spin-magnetoexcitonic ensemble in a quantum Hall system
Physical Review B: Condensed Matter and Materials Physics. 2019. Vol. 100. P. 155304-1-155304-10.
Dickmann S., Kulik L., Kuznetsov V.
The recent experimental studies of extremely long-lived macroscopic ensembles of spin-cyclotron excitons (magnetoexcitons) which have to obey the Bose-Einstein statistics signal the emergence of an excitonic coherent phase. In the present paper the theory of a weakly interacting Bose gas of spin-cyclotron excitations is developed in terms of a virial correction to the single-magnetoexciton energy. The condition for coherent-incoherent phase transition is discussed. It is expected to be strongly related to the studied long-distance interexcitonic correlations. The results obtained theoretically are discussed in terms of their agreement with specific experimental data.
Keywords: quantum Hall effect
Publication based on the results of:
Kuznetsov V. A., Kulik L. V., Velikanov M. D. et al., Physical Review B: Condensed Matter and Materials Physics 2018 Vol. 98 No. 20 P. 205303-1-205303-9
Three-particle complexes consisting of two holes in the completely filled zero-electron Landau level and an excited electron in the unoccupied first Landau level are investigated in a quantum Hall insulator. The distinctive features of these three-particle complexes are an electron-hole mass symmetry and the small energy gap of the quantum Hall insulator itself. Theoretical calculations ...
Added: November 20, 2018
Vankov A., Кайсин Б. Д., Kukushkin I., Письма в Журнал экспериментальной и теоретической физики 2018 Т. 107 № 2 С. 110-114
In the two-dimensional electron systems with strong coupling in MgZnO/ZnO heterostructures, the thermal
behavior of Ising quantum Hall ferromagnets at the filling factor nu=2 has been studied. The spin polarization
of Hall ferromagnets has been detected by measuring the signal related to the inelastic light scattering by
intrasubband spin excitons. A stepwise change in the spin polarization at ...
Added: September 11, 2018
Kulik L. V., Kuznetsov V. A., Gorbunov A. V. et al., Scientific Reports 2018 Vol. 8 No. 1 P. 1-6
We report on optical visualization of spin propagation more than 100 µm. We present an electronic system in a new state of aggregation, the magnetofermionic condensate, in which the lowest-energy spin excitations − photoexcited spin-triplet magnetoexcitons – freely propagate over long distances, in the order of a millimeter, which implies non-diffusion spin transport. Our results open ...
Added: September 3, 2018
Khrapai V., Physical Review B: Condensed Matter and Materials Physics 2023 Vol. 107 No. 24 Article L241401
A quantum Hall interferometer containing a grounded superconducting terminal is proposed. This geometry
allows to control the Andreev and normal scattering amplitudes of subgap Bogoliubov quasiparticles with the
Aharonov-Bohm phase, as well as with the constrictions defining the interferometer loop. The conductance
matrix of such a three-terminal NSN interference device exhibits a much richer behavior as compared to ...
Added: June 13, 2023
Van'kov A. V., Kukushkin I., JETP Letters 2021 Vol. 113 P. 102-114
Extraordinary multiparticle effects in quantizing magnetic fields that are manifested in strongly interacting two-dimensional electron systems in MgZnO/ZnO heterostructures have been reviewed. They are studied by the method of inelastic light scattering on two-dimensional systems with unique properties: strong Coulomb interaction characterized by the Wigner–Seitz parameters \({{r}_{s}} > 5\) and a high mobility. Studies are ...
Added: November 11, 2021
Gorbunov A., Vladimir A. Kuznetsov, Zhuravlev A. et al., Annalen der Physik 2019 P. 1800443-1800458
Experimental results on the properties of a recently discovered new collective state, the magnetofermionic condensate, are summarized herein. Condensation occurs in a fermionic system, a quantum Hall insulator (filling factor ν = 2), as a result of the formation of a dense ensemble of long-lived spin cyclotron magnetoexcitons, composite bosons. At temperatures below 1 K, ...
Added: May 29, 2019
Kuznetsov V., Кулик Л. В., Журавлёв А. С. et al., Письма в Журнал экспериментальной и теоретической физики 2018 Т. 107 № 2 С. 104-107
В спектре фотолюминесценции двумерного электронного газа в квантующем магнитном поле, при факторе заполнения электронов ν=2, в условиях фотовозбуждения неравновесного ансамбля циклотронных магнитоэкситонов, обнаружены новые линии. Их энергия лежит в области, запрещенной для одночастичных оптических переходов: в диапазоне переходов из возбужденных состояний трехчастичных трансляционно-инвариантных комплексов - магнитотрионов. Предполагается, что новые линии связаны со сложным спектром внутреннего движения ...
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A.B. Van'kov, Kukushkin I., Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 102 No. 23 P. 235424-1-235424-6
Anomalous behavior of spin stiffness is revealed in ZnO-based two-dimensional electron systems (2DESs)
with strong Coulomb interaction and Wigner-Seitz parameter r_s > 6. The spin stiffness is extracted directly from
the quadratic k-dispersion of spin excitons at ν = 1 probed by inelastic light scattering. The resulting values are
found to be dramatically rescaled compared to the case ...
Added: January 22, 2021
Belozerov E.I., Zhuravlev A. S., Kulik L.V., Bulletin of the Russian Academy of Sciences: Physics 2021 Vol. 85 No. 2 P. 174-175
A new experimental technique is proposed for studying bulk states under conditions of the fractional quantum Hall effect. ...
Added: March 30, 2022
A. B. Van'kov, Koreyev A. S., P. S. Berezhnoy et al., Physical Review B: Condensed Matter and Materials Physics 2022 Vol. 106 No. 24 Article 245308
In strongly correlated quantum Hall ferromagnets with noninteger filling factors between ν = 1 and ν =
3/2, evidence of offbeat spin textures is obtained. The platforms for the study are two-dimensional electron
systems based on MgZnO/ZnO heterostructures, in which the parameters of Zeeman and exchange energies are
inconsistent with ordinary skyrmions. Experimental probing of magnetic order is ...
Added: December 29, 2022
Zhuravlev A. S., Dickmann S., Kulik L. V. et al., Physical Review B: Condensed Matter and Materials Physics 2014 Vol. 89 P. 161301
Electron spin relaxation in a spin-polarized quantum Hall state is studied. Long spin-relaxation times that are at least an order of magnitude longer than those measured in previous experiments were observed and explained within the spin-exciton relaxation formalism. The absence of any dependence of the spin-relaxation time on the electron temperature and on the spin-exciton ...
Added: October 23, 2016
Vankov A., Kukushkin I., Письма в Журнал экспериментальной и теоретической физики 2020 Т. 112 № 1 С. 62-67
The Raman study of strongly interacting two-dimensional electron systems based on ZnO/MgZnO has revealed an anomalously intense spectral line of the anti-Stokes component of the spin exciton. This line is manifested near the filling factor v = 2 at the ferromagnetic ordering of the spin subsystem, whereas it is not observed at the paramagnetic ordering. ...
Added: January 25, 2021
Vankov A., Kukushkin I., Physical Review B: Condensed Matter and Materials Physics 2021 Vol. 104 Article 165144
In ZnO-based two-dimensional electron systems with strong Coulomb interaction, the anomalous spin-exciton
branch is revealed. As probed by inelastic light scattering, in a ferromagnetic quantum-Hall state with the filling
factor ν = 2, a spin exciton has a negative momentum dispersion with steepness dependent on the electron
density. The negative dispersion of the spin exciton is associated with ...
Added: December 20, 2021
Горбунов А. В., Кулик Л. В., Kuznetsov V. et al., Письма в Журнал экспериментальной и теоретической физики 2017 Т. 106 № 10 С. 651-654
We demonstrate that non-equilibrium spin excitations drift to macroscopically large distances in a 2D electron gas (symmetrically doped GaAs/AlGaAs quantum well) in a quantizing magnetic field at filling factor $\nu $ = 2. The effect is induced by low-temperature photoexcitation of a dense ensemble of long-lived ($\sim 1 $ ms) spin excitations − cyclotron spin-flip magnetoexcitons. The spin excitation ...
Added: December 11, 2017
Vankov A., Kaysin B. D., Kukushkin I., JETP Letters 2019 Vol. 110 No. 4 P. 296-300
The behavior of the degree of spin polarization and the specific exchange energy near the Hall ferromagnetic state with filling factor ν = 1 in strongly interacting two-dimensional electron systems in MgZnO/ZnO heterostructures is investigated. These characteristics have been determined by measuring the spectra of inelastic light scattering by the collective excitations of the electron ...
Added: October 31, 2019
Dziom V., Shuvaev A. V., Shchepetilnikov A. et al., Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 99 No. 4 Article 045305
The integer quantum Hall effect is a well-studied phenomenon at frequencies below about 100 Hz. The plateaus in high-frequency Hall conductivity were experimentally proven to retain up to 33 GHz, but the behavior at higher frequencies has remained largely unexplored. Using continuous-wave terahertz spectroscopy, the complex Hall conductivity of GaAs/AlGaAs heterojunctions was studied in the ...
Added: December 11, 2020
Vankov A., Kaysin B. D., Kukushkin I., Physical Review B: Condensed Matter and Materials Physics 2018 Vol. 98 P. 121412-121412
We investigate the impact of Coulomb correlations on the low-energy collective excitations in two-dimensional electron systems in the quantum Hall state ν = 2. The collective excitations are studied using inelastic light scattering in the set of MgZnO/ZnO heterostructures with high-mobility two-dimensional electrons. The study focuses on the lowest-energy collective excitations in the paramagnetic state ...
Added: November 25, 2018
Zhuravlev A. S., Kulik L.V., Kuznetsov V. A. et al., JETP Letters 2018 Vol. 108 No. 6 P. 419-422
The spin polarization features of an electron system and the relaxation of nonequilibrium spin excitations near an even-denominator fractional state of 3/2 in a two-dimensional electron system based on the GaAs/AlGaAs heterostructure are experimentally investigated. It is shown that the 3/2 state is a singular point in the filling factor dependence of the spin ordering ...
Added: November 30, 2018
Kukushkin I., Vankov A., Kaysin B., Physical Review B: Condensed Matter and Materials Physics 2017 Vol. 96 P. 235401-1-235401-8
We perform a magneto-optical study of a two-dimensional electron systems in the regime of the Stoner
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magnetic field, the transition between two rivaling phases, paramagnetic and ferromagnetic, is traced in ...
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Vankov A., Kaysin B. D., Volosheniuk S. et al., Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 100 No. 4 P. 041407-1-041407-5
An unusual behavior of the exchange energy scale of a quantum Hall ferromagnet with ν=1 was found in strongly correlated two-dimensional electron systems based on MgZnO/ZnO heterostructures. The exchange contribution, entering the energy of a collective excitation, was probed by means of inelastic light scattering. It was established that, in a wide range of electron densities corresponding ...
Added: October 31, 2019
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 ...
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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 ...
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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
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Added: May 10, 2017