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Title: Coupled Dzyaloshinskii walls and their current-induced dynamics by the spin Hall effect

Abstract

The nucleation of domain walls in ultrathin ferromagnetic/heavy-metal bilayers is studied by means of micromagnetic simulations. In the presence of interfacial Dzyaloshinskii-Moriya interaction, the nucleated walls naturally adopt a homochiral configuration with internal magnetization pointing antiparallely. The interaction between these walls was analyzed and described in terms of a classical dipolar force between the magnetic moments of the walls, which couples their dynamics. Additionally, the current-induced motion of two homochiral walls in the presence of longitudinal fields was also studied by means of a simple one-dimensional model and micromagnetic modeling, considering both one free-defect strip and another one with random edge roughness. It is evidenced that in the presence of pinning due to edge roughness, the in-plane longitudinal field introduces an asymmetry in the current-induced depinning, in agreement with recent experimental results.

Authors:
 [1];  [2]
  1. Dpto. de Fisica Aplicada, Universidad de Salamanca, Plaza de los Caídos s/n, E-37008 Salamanca (Spain)
  2. Dpto. de Electricidad y Electrónica, Universidad de Valladolid, Paseo de Belén, 7, E-47011 Valladolid (Spain)
Publication Date:
OSTI Identifier:
22308731
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ASYMMETRY; CONFIGURATION; CRYSTAL DEFECTS; CURRENTS; HALL EFFECT; HEAVY METALS; INTERACTIONS; LAYERS; MAGNETIC MOMENTS; MAGNETIZATION; ONE-DIMENSIONAL CALCULATIONS; RANDOMNESS; ROUGHNESS; SIMULATION; SPIN

Citation Formats

Martínez, Eduardo, E-mail: edumartinez@usal.es, and Alejos, Óscar. Coupled Dzyaloshinskii walls and their current-induced dynamics by the spin Hall effect. United States: N. p., 2014. Web. doi:10.1063/1.4889848.
Martínez, Eduardo, E-mail: edumartinez@usal.es, & Alejos, Óscar. Coupled Dzyaloshinskii walls and their current-induced dynamics by the spin Hall effect. United States. doi:10.1063/1.4889848.
Martínez, Eduardo, E-mail: edumartinez@usal.es, and Alejos, Óscar. Mon . "Coupled Dzyaloshinskii walls and their current-induced dynamics by the spin Hall effect". United States. doi:10.1063/1.4889848.
@article{osti_22308731,
title = {Coupled Dzyaloshinskii walls and their current-induced dynamics by the spin Hall effect},
author = {Martínez, Eduardo, E-mail: edumartinez@usal.es and Alejos, Óscar},
abstractNote = {The nucleation of domain walls in ultrathin ferromagnetic/heavy-metal bilayers is studied by means of micromagnetic simulations. In the presence of interfacial Dzyaloshinskii-Moriya interaction, the nucleated walls naturally adopt a homochiral configuration with internal magnetization pointing antiparallely. The interaction between these walls was analyzed and described in terms of a classical dipolar force between the magnetic moments of the walls, which couples their dynamics. Additionally, the current-induced motion of two homochiral walls in the presence of longitudinal fields was also studied by means of a simple one-dimensional model and micromagnetic modeling, considering both one free-defect strip and another one with random edge roughness. It is evidenced that in the presence of pinning due to edge roughness, the in-plane longitudinal field introduces an asymmetry in the current-induced depinning, in agreement with recent experimental results.},
doi = {10.1063/1.4889848},
journal = {Journal of Applied Physics},
number = 2,
volume = 116,
place = {United States},
year = {Mon Jul 14 00:00:00 EDT 2014},
month = {Mon Jul 14 00:00:00 EDT 2014}
}
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