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Title: Effect of temperature and magnetic field on disorder in semiconductor structures

Abstract

We present the results of consistent theoretical analysis of various factors that may lead to influence of temperature and external magnetic field on disorder in semiconductor structures. Main attention is paid to quantum well (QW) structures in which only QWs or both QW and barriers are doped (the doping level is assumed to be close to the value corresponding to the metal–insulator transition). The above factors include (i) ionization of localized states to the region of delocalized states above the mobility edge, which is presumed to exist in the impurity band; (ii) the coexistence in the upper and lower Hubbard bands (upon doping of QWs as well as barriers); in this case, in particular, the external magnetic field determines the relative contribution of the upper Hubbard band due to spin correlations at doubly filled sites; and (iii) the contribution of the exchange interaction at pairs of sites, in which the external magnetic field can affect the relation between ferromagnetic and antiferromagnetic configurations. All these factors, which affect the structure and degree of disorder, lead to specific features in the temperature dependence of resistivity and determine specific features of the magnetoresistance. Our conclusions are compared with available experimental data.

Authors:
;  [1]
  1. Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)
Publication Date:
OSTI Identifier:
22617063
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 124; Journal Issue: 2; Other Information: Copyright (c) 2017 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIFERROMAGNETISM; COMPARATIVE EVALUATIONS; CORRELATIONS; DIFFUSION BARRIERS; DOPED MATERIALS; EXCHANGE INTERACTIONS; IMPURITIES; MAGNETIC FIELDS; MAGNETORESISTANCE; PHASE TRANSFORMATIONS; QUANTUM WELLS; SEMICONDUCTOR MATERIALS; SIMULATION; SPIN; TEMPERATURE DEPENDENCE

Citation Formats

Agrinskaya, N. V., E-mail: nina.agrins@mail.ioffe.ru, and Kozub, V. I. Effect of temperature and magnetic field on disorder in semiconductor structures. United States: N. p., 2017. Web. doi:10.1134/S1063776117010095.
Agrinskaya, N. V., E-mail: nina.agrins@mail.ioffe.ru, & Kozub, V. I. Effect of temperature and magnetic field on disorder in semiconductor structures. United States. doi:10.1134/S1063776117010095.
Agrinskaya, N. V., E-mail: nina.agrins@mail.ioffe.ru, and Kozub, V. I. Wed . "Effect of temperature and magnetic field on disorder in semiconductor structures". United States. doi:10.1134/S1063776117010095.
@article{osti_22617063,
title = {Effect of temperature and magnetic field on disorder in semiconductor structures},
author = {Agrinskaya, N. V., E-mail: nina.agrins@mail.ioffe.ru and Kozub, V. I.},
abstractNote = {We present the results of consistent theoretical analysis of various factors that may lead to influence of temperature and external magnetic field on disorder in semiconductor structures. Main attention is paid to quantum well (QW) structures in which only QWs or both QW and barriers are doped (the doping level is assumed to be close to the value corresponding to the metal–insulator transition). The above factors include (i) ionization of localized states to the region of delocalized states above the mobility edge, which is presumed to exist in the impurity band; (ii) the coexistence in the upper and lower Hubbard bands (upon doping of QWs as well as barriers); in this case, in particular, the external magnetic field determines the relative contribution of the upper Hubbard band due to spin correlations at doubly filled sites; and (iii) the contribution of the exchange interaction at pairs of sites, in which the external magnetic field can affect the relation between ferromagnetic and antiferromagnetic configurations. All these factors, which affect the structure and degree of disorder, lead to specific features in the temperature dependence of resistivity and determine specific features of the magnetoresistance. Our conclusions are compared with available experimental data.},
doi = {10.1134/S1063776117010095},
journal = {Journal of Experimental and Theoretical Physics},
number = 2,
volume = 124,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2017},
month = {Wed Feb 15 00:00:00 EST 2017}
}
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