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Title: Soliton dynamics in a spin nematic

Abstract

One-dimensional localized waves, which can be considered as soliton elementary excitations, exist in a magnet with a unit spin and comparable bilinear and biquadratic spin-spin interactions, with which the state of spin nematic is realized. These excitations are characterized by a certain momentum P and a certain energy E. The structure of these solitons has been found, and the E = E(P) dependence, which plays the role of the dispersion law of these soliton elementary excitations, has been constructed. The energy of a soliton with a certain momentum is shown to be lower than that of the quasiparticles of a linear theory. At small momenta, these E = E(P) dependences of the soliton and quasiparticles coincide asymptotically. The dependence of the soliton energy on the soliton momentum is a periodic function with a period P{sub 0} = {pi}{Dirac_h}/a, whose value does not depend on exchange integrals and depends only on a single crystal parameter, namely, the interatomic distance a. These soliton excitations have common features with the so-called Lieb states, which are well known in many condensed matter models.

Authors:
 [1];  [2]
  1. National Academy of Sciences of Ukraine, Institute of Magnetism (Ukraine), E-mail: bivanov@i.com.ua
  2. Taras Shevchenko University (Ukraine)
Publication Date:
OSTI Identifier:
21072525
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 104; Journal Issue: 2; Other Information: DOI: 10.1134/S106377610702015X; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; EXCITATION; FUNCTIONS; INTEGRALS; INTERATOMIC DISTANCES; J-J COUPLING; MONOCRYSTALS; ONE-DIMENSIONAL CALCULATIONS; PERIODICITY; SOLITONS; SPIN

Citation Formats

Ivanov, B. A., and Khymyn, R. S. Soliton dynamics in a spin nematic. United States: N. p., 2007. Web. doi:10.1134/S106377610702015X.
Ivanov, B. A., & Khymyn, R. S. Soliton dynamics in a spin nematic. United States. doi:10.1134/S106377610702015X.
Ivanov, B. A., and Khymyn, R. S. Sun . "Soliton dynamics in a spin nematic". United States. doi:10.1134/S106377610702015X.
@article{osti_21072525,
title = {Soliton dynamics in a spin nematic},
author = {Ivanov, B. A. and Khymyn, R. S.},
abstractNote = {One-dimensional localized waves, which can be considered as soliton elementary excitations, exist in a magnet with a unit spin and comparable bilinear and biquadratic spin-spin interactions, with which the state of spin nematic is realized. These excitations are characterized by a certain momentum P and a certain energy E. The structure of these solitons has been found, and the E = E(P) dependence, which plays the role of the dispersion law of these soliton elementary excitations, has been constructed. The energy of a soliton with a certain momentum is shown to be lower than that of the quasiparticles of a linear theory. At small momenta, these E = E(P) dependences of the soliton and quasiparticles coincide asymptotically. The dependence of the soliton energy on the soliton momentum is a periodic function with a period P{sub 0} = {pi}{Dirac_h}/a, whose value does not depend on exchange integrals and depends only on a single crystal parameter, namely, the interatomic distance a. These soliton excitations have common features with the so-called Lieb states, which are well known in many condensed matter models.},
doi = {10.1134/S106377610702015X},
journal = {Journal of Experimental and Theoretical Physics},
number = 2,
volume = 104,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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