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Title: Nonlinear dynamics of domain walls with cross-ties

Abstract

The dynamic behavior of a domain wall with cross-ties is analyzed on the basis of micromagnetic simulation with exact allowance for all main (exchange, magnetoanisotropic, and magnetostatic) interactions in thin magnetically uniaxial ferromagnetic films with planar anisotropy. It is found that the peculiarities of motion of such domain walls are closely related to the behavior of topological defects in the magnetization distribution (generation, motion, and annihilation of vortex–antivortex pairs on the film surface and Bloch points). We observe three different regimes of motion (stationary, periodic, and turbulent regimes), each of which is realized in a certain range of fields oriented along the easy magnetization axis. It is shown that the experimentally observed dynamic bends of the walls with cross-ties are determined by the type of motion of vortices and antivortices. The velocities of domain walls in different regimes are calculated, and the dynamic configurations of the magnetization and existing dynamic transitions between them are investigated.

Authors:
 [1];  [2];  [1]
  1. Russian Academy of Sciences, Institute of Metal Physics, Ural Branch (Russian Federation)
  2. Ural Federal University (Russian Federation)
Publication Date:
OSTI Identifier:
22617226
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:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; ANNIHILATION; CONFIGURATION; DEFECTS; DISTRIBUTION; FILMS; MAGNETIZATION; NONLINEAR PROBLEMS; PERIODICITY; SIMULATION; SURFACES; TOPOLOGY; VORTICES; WALLS

Citation Formats

Dubovik, M. N., E-mail: dubovik@imp.uran.ru, Zverev, V. V., and Filippov, B. N. Nonlinear dynamics of domain walls with cross-ties. United States: N. p., 2016. Web. doi:10.1134/S1063776116050162.
Dubovik, M. N., E-mail: dubovik@imp.uran.ru, Zverev, V. V., & Filippov, B. N. Nonlinear dynamics of domain walls with cross-ties. United States. doi:10.1134/S1063776116050162.
Dubovik, M. N., E-mail: dubovik@imp.uran.ru, Zverev, V. V., and Filippov, B. N. 2016. "Nonlinear dynamics of domain walls with cross-ties". United States. doi:10.1134/S1063776116050162.
@article{osti_22617226,
title = {Nonlinear dynamics of domain walls with cross-ties},
author = {Dubovik, M. N., E-mail: dubovik@imp.uran.ru and Zverev, V. V. and Filippov, B. N.},
abstractNote = {The dynamic behavior of a domain wall with cross-ties is analyzed on the basis of micromagnetic simulation with exact allowance for all main (exchange, magnetoanisotropic, and magnetostatic) interactions in thin magnetically uniaxial ferromagnetic films with planar anisotropy. It is found that the peculiarities of motion of such domain walls are closely related to the behavior of topological defects in the magnetization distribution (generation, motion, and annihilation of vortex–antivortex pairs on the film surface and Bloch points). We observe three different regimes of motion (stationary, periodic, and turbulent regimes), each of which is realized in a certain range of fields oriented along the easy magnetization axis. It is shown that the experimentally observed dynamic bends of the walls with cross-ties are determined by the type of motion of vortices and antivortices. The velocities of domain walls in different regimes are calculated, and the dynamic configurations of the magnetization and existing dynamic transitions between them are investigated.},
doi = {10.1134/S1063776116050162},
journal = {Journal of Experimental and Theoretical Physics},
number = 1,
volume = 123,
place = {United States},
year = 2016,
month = 7
}
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