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Title: Magnetism and superconductivity in a quasi-2D anisotropic system doped with charge carriers

Abstract

The theory of multiband superconducting systems with variable density of charge carriers is analyzed. The possibility of emergence of nonphonon high-temperature superconductivity due to the predominance of electron–electron interband interactions over intraband interactions, as well as due to the fact that the thermodynamic and magnetic properties of multiband systems in the superconducting phase differ qualitatively from those of single-band systems, is indicated. Phase transitions in a quasi-2D anisotropic medium upon a change in the carrier concentration, i.e., a transition from the commensurate to the incommensurate state of the spin density wave, are analyzed. Such a transition is observed when the Umklapp processes in the lattice structure are taken into account. These processes facilitate a deviation of wavevector Q of the spin density wave from 2k{sub F}, as well as a displacement of the bandgap relative to the Fermi surface. This leads to the generation of free charge carriers and the possibility of superconductivity. It is shown that superconductivity accompanies the magnetism. The conditions for the coexistence of these two phenomena are determined.

Authors:
 [1]
  1. Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of)
Publication Date:
OSTI Identifier:
22617228
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 123; Journal Issue: 1; Other Information: Copyright (c) 2016 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; ANISOTROPY; CARRIERS; CHARGE CARRIERS; CONCENTRATION RATIO; DOPED MATERIALS; ELECTRONS; FERMI LEVEL; MAGNETIC PROPERTIES; MAGNETISM; PHASE TRANSFORMATIONS; SPIN; SUPERCONDUCTIVITY; THERMODYNAMICS; UMKLAPP PROCESSES; FUNDAMENTAL INTERACTIONS

Citation Formats

Palistrant, M. E., E-mail: mepalistrant@yandex.ru. Magnetism and superconductivity in a quasi-2D anisotropic system doped with charge carriers. United States: N. p., 2016. Web. doi:10.1134/S1063776116050198.
Palistrant, M. E., E-mail: mepalistrant@yandex.ru. Magnetism and superconductivity in a quasi-2D anisotropic system doped with charge carriers. United States. doi:10.1134/S1063776116050198.
Palistrant, M. E., E-mail: mepalistrant@yandex.ru. 2016. "Magnetism and superconductivity in a quasi-2D anisotropic system doped with charge carriers". United States. doi:10.1134/S1063776116050198.
@article{osti_22617228,
title = {Magnetism and superconductivity in a quasi-2D anisotropic system doped with charge carriers},
author = {Palistrant, M. E., E-mail: mepalistrant@yandex.ru},
abstractNote = {The theory of multiband superconducting systems with variable density of charge carriers is analyzed. The possibility of emergence of nonphonon high-temperature superconductivity due to the predominance of electron–electron interband interactions over intraband interactions, as well as due to the fact that the thermodynamic and magnetic properties of multiband systems in the superconducting phase differ qualitatively from those of single-band systems, is indicated. Phase transitions in a quasi-2D anisotropic medium upon a change in the carrier concentration, i.e., a transition from the commensurate to the incommensurate state of the spin density wave, are analyzed. Such a transition is observed when the Umklapp processes in the lattice structure are taken into account. These processes facilitate a deviation of wavevector Q of the spin density wave from 2k{sub F}, as well as a displacement of the bandgap relative to the Fermi surface. This leads to the generation of free charge carriers and the possibility of superconductivity. It is shown that superconductivity accompanies the magnetism. The conditions for the coexistence of these two phenomena are determined.},
doi = {10.1134/S1063776116050198},
journal = {Journal of Experimental and Theoretical Physics},
number = 1,
volume = 123,
place = {United States},
year = 2016,
month = 7
}
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