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Title: Controlling the stability of both the structure and velocity of domain walls in magnetic nanowires

Abstract

For magnetic nanowire devices, the precise control of both domain wall (DW) motion and pinning behaviour is essential for reliable functional performance. The domain wall velocity and wall structure are typically sensitive to the driving field or spin-polarized current, and the pinning behaviour depends on the walls' structure and chirality, leading to variability in behaviour. Here, a systematic study combining experimental measurements and micromagnetic simulations of planar nanowires with small fixed-angle structural modulations on both edges was undertaken to study the domain wall reversal regime. A phase diagram for the reversal field as a function of modulation amplitude was obtained that shows that three DW reversal regime. A range of field and modulation amplitudes were identified in which stable DW reversal occurs, where the wall velocity is constant as a function of field and the wall structure is stable, which is well suited to applications.

Authors:
;  [1]
  1. Centre for Materials Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)
Publication Date:
OSTI Identifier:
22594352
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; CHIRALITY; CONTROL; MODULATION; NANOWIRES; PHASE DIAGRAMS; SIMULATION; SPIN; SPIN ORIENTATION; STABILITY; VELOCITY; WALLS

Citation Formats

Brandão, J., and Atkinson, D. Controlling the stability of both the structure and velocity of domain walls in magnetic nanowires. United States: N. p., 2016. Web. doi:10.1063/1.4960201.
Brandão, J., & Atkinson, D. Controlling the stability of both the structure and velocity of domain walls in magnetic nanowires. United States. doi:10.1063/1.4960201.
Brandão, J., and Atkinson, D. Mon . "Controlling the stability of both the structure and velocity of domain walls in magnetic nanowires". United States. doi:10.1063/1.4960201.
@article{osti_22594352,
title = {Controlling the stability of both the structure and velocity of domain walls in magnetic nanowires},
author = {Brandão, J. and Atkinson, D.},
abstractNote = {For magnetic nanowire devices, the precise control of both domain wall (DW) motion and pinning behaviour is essential for reliable functional performance. The domain wall velocity and wall structure are typically sensitive to the driving field or spin-polarized current, and the pinning behaviour depends on the walls' structure and chirality, leading to variability in behaviour. Here, a systematic study combining experimental measurements and micromagnetic simulations of planar nanowires with small fixed-angle structural modulations on both edges was undertaken to study the domain wall reversal regime. A phase diagram for the reversal field as a function of modulation amplitude was obtained that shows that three DW reversal regime. A range of field and modulation amplitudes were identified in which stable DW reversal occurs, where the wall velocity is constant as a function of field and the wall structure is stable, which is well suited to applications.},
doi = {10.1063/1.4960201},
journal = {Applied Physics Letters},
number = 6,
volume = 109,
place = {United States},
year = {Mon Aug 08 00:00:00 EDT 2016},
month = {Mon Aug 08 00:00:00 EDT 2016}
}
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