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Magnetodipolar interaction and quasiparticles delocalization in disordered quantum magnets
Journal of Magnetism and Magnetic Materials. 2022. Vol. 560. Article 169640.
Oleg I. Utesov
It is well-known that disordered quantum magnets usually host localized elementary excitations in gapped
phases. Here we show that long-range magnetodipolar interaction can lead to quasiparticles delocalization in
the three-dimensional case, similarly to the phenomenon previously described for localized vibrational modes
in disordered solids. Employing renormalization group-like ideas, the average eigenmode occupation number
is found to scale with the system size, which also leads to sub-diffusive dynamical properties of the system.
Blinov V. N., Наноструктуры. Математическая физика и моделирование 2014 Т. 10 № 1 С. 5-28
Учёт дальнодействующих взаимодействий является непростой особенностью компьютерного моделирования систем физики конденсированных сред. В то время как в моделировании кристаллов метод суммирования Эвальда позволяет учесть их естественную трансляционную симметрию, в случае жидких систем подобные схемы носят, скорее, эмпирический характер, и основаны на определённых приближениях и результатах моделирования. В данном обзоре рассмотрены основные методы, применяемые при моделировании ...
Added: June 6, 2014
Murod S. Bahovadinov, Kurlov D., Altshuler B. et al., 2022 Vol. 76 No. 7 Article 116
We study effects of disorder on eigenstates of 1D two-component fermions with infinitely strong Hubbard repulsion. We demonstrate that the spin-independent (potential) disorder reduces the problem to the one-particle Anderson localization taking place at arbitrarily weak disorder. In contrast, a random magnetic field can cause reentrant many-body localization–delocalization transitions. Surprisingly weak magnetic field destroys one-particle ...
Added: December 13, 2022
Tikhonov K., Ioselevich A., Feigelman M., Annals of Physics 2021 Vol. 435 Article 168524
We study deterministic power-law quantum hopping model with an amplitude J(r)~r^{-\beta} and local Gaussian disorder in low dimensions d=1 or 2 under the condition d<\beta<3/2\d. We demonstrate unusual combination of exponentially decreasing density of the ”tail states” and localization–delocalization transition (as function of disorder strength W) pertinent to a small (vanishing in thermodynamic limit) fraction ...
Added: October 17, 2021
Kurlov D., Bakhovadinov M., Matveenko S. et al., Physical Review B: Condensed Matter and Materials Physics 2023 Vol. 107 No. 184202
We study the one-dimensional Hubbard model for two-component fermions with infinitely strong on-site repulsion (t−0 model) in the presence of disorder. Our analytical treatment demonstrates that the type of disorder drastically changes the nature of the emerging phases. The case of spin-independent disorder can be treated as a single-particle problem with Anderson localization. On the ...
Added: October 10, 2023
O.I. Utesov, Journal of Magnetism and Magnetic Materials 2021 Vol. 524 P. 167616
The analytical theory of density of states (DOS) in three-dimensional quantum magnets with the bond disorder is proposed based on the self-consistent T-matrix
approximation (SCTMA). It successfully describes the DOS both for resonant and non-resonant scattering, whose emergence is governed by the ratio of scattering
length and the average distance between impurities, which concentration is denoted as ...
Added: January 14, 2021
Sherbakov A., Oleg I. Utesov, Journal of Magnetism and Magnetic Materials 2021 Vol. 518 P. 167390
Motivated by recent experiments on quantum magnet NiCl2-4SC(NH2)2 (DTN) and its Br-doped counterpart DTNX we propose a theoretical description of optical magnon branch in the antiferromagnet with large single-ion
anisotropy in the magnetically ordered phase. In the framework of the 1/S expansion we derive analytical
expressions for optical magnon with \bf{k} = 0 energy magnetic field dependence ...
Added: January 15, 2021
Nosov P. A., Burmistrov I., Raghu S., Physical Review Letters 2020 Vol. 125 No. 25 P. 1-7
The interplay of interactions and disorder in two-dimensional (2D) electron systems has actively been studied for decades. The paradigmatic approach involves starting with a clean Fermi liquid and perturbing the system with both disorder and interactions. Instead, we start with a clean non-Fermi liquid near a 2D ferromagnetic quantum critical point and consider the effects ...
Added: January 28, 2021
O. Valba, Gorsky A., JETP Letters 2022 Vol. 116 No. 6 P. 398-404
We study numerically the Anderson model on partially disordered random regular graphs considered as the toy model for a Hilbert space of interacting disordered many-body system. The protected subsector of zero-energy states in a many-body system corresponds to clean nodes in random regular graphs ensemble. Using adjacent gap ratio statistics and inverse participation ratio we ...
Added: October 29, 2022
Kolokolov I., Physica D: Nonlinear Phenomena 1995 Vol. 86 No. 1-2 P. 134-148
start from the derivation of the Abrikosov-Ryzhkin model for the 1D random potential problem. In its framework I find closed functional representations for various physical quantities. The representation uses number-valued fields only. These functional integrals are calculated exactly without the use of any perturbative expansions. Expressions for the multipoint densities correlators are obtained. These correlators ...
Added: March 28, 2017
Babkin S. S., I. S. Burmistrov, Physical Review B: Condensed Matter and Materials Physics 2023 Vol. 108 No. 20 Article 205429
Generalized multifractality characterizes system size dependence of pure scaling local observables at Anderson transitions in all 10 symmetry classes of disordered systems. Recently, the concept of generalized multifractality has been extended to boundaries of critical disordered noninteracting systems. Here we study the generalized boundary multifractality in the presence of electron-electron interaction, focusing on the spin ...
Added: January 29, 2024
Kolokolov I., International Journal of Modern Physics B 1996 Vol. 10 No. 18-19 P. 2189-2215
A number of problems in statistical physics can be reformulated in terms of a two-state system evolving in a random field. The corresponding evolution operator can be written in the form of time-ordered operator exponential. Functional formalism allows us to rewrite the latter as a product of usual matrix exponentials using a nonlinear change of ...
Added: March 28, 2017
Tikhonov K., Mirlin A. D., Skvortsov M. A., Physical Review B: Condensed Matter and Materials Physics 2016 Vol. 94 P. 220203-1-220203-6
A numerical study of Anderson transition on random regular graphs (RRGs) with diagonal disorder is performed.
The problem can be described as a tight-binding model on a lattice with N sites that is locally a tree with constant connectivity.
In a certain sense, the RRG ensemble can be seen as an infinite-dimensional (d→∞) cousin of the Anderson ...
Added: March 9, 2017
Tikhonov K., Mirlin A. D., Physical Review B: Condensed Matter and Materials Physics 2016 Vol. 94 P. 184203-1-184203-16
We investigate analytically and numerically eigenfunction statistics in a disordered system on a finite Bethe lattice (Cayley tree). We show that the wave-function amplitude at the root of a tree is distributed fractally in a large part of the delocalized phase. The fractal exponents are expressed in terms of the decay rate and the velocity ...
Added: March 9, 2017
Kolokolov I., Journal of Experimental and Theoretical Physics 1993 Vol. 76 No. 6 P. 1099-1109
Starting from the Abrikosov-Ryzhkin formulation of the
1D random potential problem I find closed functional representations
for various physical quantities. These functional integrals are
calculated exactly without the use of any perturbative expansions.
The expressions for the multipoint densities correlators are
obtained. Then I evaluate the mean square dispersion of the size
of localized wave functions. As a physical application of ...
Added: March 29, 2017
Kolokolov I., EPL 1994 Vol. 28 No. 3 P. 193-196
For a given wave function one can define a quantity μE having the meaning of its inverse spatial size. The Laplace transform of the distribution function P(μE) is calculated analytically for a 1D disordered sample with a finite length L. ...
Added: March 28, 2017
Tikhonov K., Mirlin A. D., Physical Review B: Condensed Matter and Materials Physics 2021 Vol. 103 No. 6 Article 064204
We explore correlations of eigenstates around the many-body localization (MBL) transition in their dependence on the energy difference (frequency) ω and disorder W. In addition to the genuine many-body problem, XXZ spin chain in random field, we consider localization on random regular graphs that serves as a toy model of the MBL transition. Both models ...
Added: February 26, 2021
Tikhonov K., Mirlin A. D., Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 99 No. 2 P. 024202-1-024202-25
Dynamical and spatial correlations of eigenfunctions as well as energy level correlations in the Anderson model on random regular graphs (RRG) are studied. We consider the critical point of the Anderson transition and the delocalized phase. In the delocalized phase near the transition point, the observables show a broad critical regime for system sizes N ...
Added: January 7, 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 ...
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
Загорский Д. Л., Долуденко И. М., Каневский В. М. et al., Известия РАН. Серия физическая 2021 Т. 85 № 8 С. 1088-1094
FeCo and FeNi alloyed nanowires (NW) were obtained by the matrix synthesis method: the effect of the
growth voltage and the effect of using a reference electrode were studied. It is shown that the composition of
FeNi nanowires strongly depends on the growth potential (with its increase, the bcc structure is changing into
fcc), and it is also ...
Added: November 12, 2021
Panina I., Balandin S., Tsarev A. et al., International Journal of Molecular Sciences 2023 Vol. 24 No. 2 P. 1
To date, a number of lantibiotics have been shown to use lipid II — a highly conserved peptidoglycan precursor in the cytoplasmic membrane of bacteria — as their molecular target. The α-component (Lchα) of the two-component lantibiotic lichenicidin (Lchα), previously isolated from the Bacillus licheniformis VK21 strain, seems to contain two putative lipid II binding ...
Added: February 21, 2023