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## Interaction-induced metallicity in a two-dimensional disordered non-Fermi liquid

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 of disorder. In contrast with the disordered Fermi liquid, we find that our model does not suffer from runaway flows to strong coupling and the system has a marginally stable fixed point with perfect conduction.

Publication based on the results of:

Tikhonov K., A.D. Mirlin, 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

Tikhonov K., A.D. Mirlin, 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., Alexander Davydovych Mirlin, 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

Murod S. Bahovadinov, Sergey I. Matveenko, Journal of Physics: Condensed Matter 2022 Vol. 34 No. 31 Article 315601

In quasi-1D conducting nanowires spin-orbit coupling destructs spin-charge separation, intrinsic to Tomonaga-Luttinger liquid (TLL). We study renormalization of a single scattering impurity in a such liquid. Performing bosonization of low-energy excitations and exploiting perturbative renormalization analysis we extend the phase portrait in $K_\sigma - K_\rho$ space, obtained previously for TLL with decoupled spin-charge channels ...

Added: May 20, 2022

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., 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

Oleg I. Utesov, Journal of Magnetism and Magnetic Materials 2022 Vol. 560 Article 169640

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 ...

Added: September 27, 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

Tikhonov K., Alexander Davydovych Mirlin, Mikhail Andreevich Skvortsov, 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

Murod Bahovadinov, Denis Kurlov, Boris Altshuler et al., Many-body localization of 1D disordered impenetrable two-component fermions / Cornell University. Series cond-mat "arxiv.org". 2021.

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: May 26, 2022

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

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

Murod Bahovadinov, Denis Kurlov, Sergey I. Matveenko et al., Many-body localization transition in a frustrated XY chain / Cornell University. Series cond-mat "arxiv.org". 2021.

We demonstrate many-body localization (MBL) transition in a one-dimensional isotropic XY chain with a weak next-nearest-neighbor frustration in a random magnetic field. We perform finite-size exact diagonalization calculations of level-spacing statistics and fractal dimensions to characterize the MBL transition with increasing the random field amplitude. An equivalent representation of the model in terms of spinless ...

Added: May 20, 2022

Terekhovich V., Эпистемология и философия науки 2019 Т. 56 № 1 С. 169-184

The framework of simple opposition realism - anti-realism is not enough to analyze the views on the reality of unobservable objects of quantum theory. First, it is necessary to distinguish between realism in relation to the theory and realism in relation to the theory’s objects. Secondly, realism in relation to classical objects can be combined, ...

Added: February 12, 2020

M.Yu. Kagan, JETP Letters 2016 Vol. 103 No. 11 P. 728-738

In this short review, we first discuss the results, which are mainly devoted to the generalizations of the famous Kohn–Luttinger mechanism of superconductivity in purely repulsive fermion systems at low electron densities. In the context of repulsive-U Hubbard model and Shubin–Vonsovsky model we consider briefly the superconducting phase diagrams and the symmetries of the order parameter ...

Added: November 18, 2016

I.Kolokolov, Lebedev V., Michael Chertkov et al., Journal of Lightwave Technology 2004 Vol. 22 No. 4 P. 1155-1168

This paper presents a method that allows evaluating the performance of an optical fiber system where bit errors result from a complex interplay of spontaneous noise generated in optical amplifiers and birefringent disorder of the transmission fiber. We demonstrate that in the presence of temporal fluctuations of birefringence characteristics, the bit-error rate (BER) itself is ...

Added: February 23, 2017

Alfimov M., Alexey Litvinov, Journal of High Energy Physics 2022 No. 01 Article 43

We study regularization scheme dependence of beta-function for sigma models with two-dimensional target space. Working within four-loop approximation, we conjecture the scheme in which the beta-function retains only two tensor structures up to certain terms containing zeta_3. Using this scheme, we provide explicit solutions to RG flow equation corresponding to Yang-Baxter- and lambda-deformed SU(2)/U(1) sigma ...

Added: February 1, 2022

Дарья Дмитриевна Ружицкая, Алексей Андреевич САМОЙЛЕНКО, Алексей Дмитриевич Иванов 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

Nagaev K., Андрей Андреевич Маношин, Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 102 Article 155411

We calculate the electrical and thermal conductivity of a two-dimensional electron gas with strong spin-orbit
coupling in which the scattering is dominated by electron-electron collisions. Despite the apparent absence of
Galilean invariance in the system, the two-particle scattering does not affect the electrical conductivity above
the band-crossing point where both helicity bands are filled. Below the band-crossing point ...

Added: October 14, 2021

Yu.E. Lozovik, Станислав Леонидович Огарков, A.A. Sokolik, Physical Review B: Condensed Matter and Materials Physics 2012 Vol. 86 No. 04-5429 P. 1-6

Condensation of pairs formed by spatially separated electrons and holes in a system of two isolated graphene layers is studied beyond the mean-field approximation. Suppression of the screening of the pairing interaction at large distances, caused by the appearance of the gap, is considered self-consistently. A mutual positive feedback between the appearance of the gap ...

Added: March 14, 2013

Maslov V., Теоретическая и математическая физика 2019 Т. 201 № 1 С. 65-83

We study the process of a nucleon separating from an atomic nucleus from the mathematical standpoint
using experimental values of the binding energy for the nucleus of the given substance. A nucleon becomes
a boson at the instant of separating from a fermionic nucleus. We study the further transformations of
boson and fermion states of separation in a ...

Added: November 1, 2019

M.: Faculty of Physics, MSU, 2017

The Low Temperature Physics Conference is an international event held every three years, under the auspices of the IUPAP through its Commission C5 on Low Temperature Physics. The aim of these conferences is to exchange information and views among the members of the international scientific community in the general field of Low Temperature Physics. It ...

Added: October 1, 2017

Min Namkung, Kwon Younghun, 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., И.М. Долуденко, В. М. Каневский 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