Domain wall pinning and domain wall resistivity in notched <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>La</mml:mi><mml:mrow><mml:mn>0.7</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi>Sr</mml:mi><mml:mrow><mml
Creation and manipulation of magnetic domain walls (DWs) are a core subject of research in developing prototype devices for spintronic applications. DWs can be created artificially and moved by applying either a magnetic field or an electric current, as has been extensively investigated. Here, we study the DW pinning and depinning in half-metallic ferromagnetic <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:msub><a:mi>La</a:mi><a:mrow><a:mn>0.7</a:mn></a:mrow></a:msub><a:msub><a:mi>Sr</a:mi><a:mrow><a:mn>0.3</a:mn></a:mrow></a:msub><a:msub><a:mi>MnO</a:mi><a:mn>3</a:mn></a:msub></a:mrow></a:math> nanostructures with a notch that is about 90% of the width of the wire. By measuring the magnetoresistance of the notched wires while sweeping the magnetic field, we unambiguously observe DW pinning and depinning from 10 to 300 K. Analysis of the temperature dependence reveals that both <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mrow><b:mi mathvariant="normal">Δ</b:mi><b:mi>R</b:mi></b:mrow></b:math> (the DW resistance) and <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mrow><d:mi mathvariant="normal">Δ</d:mi><d:mi>R</d:mi><d:mo>/</d:mo><d:msub><d:mi>R</d:mi><d:mn>0</d:mn></d:msub></d:mrow></d:math> (<f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:msub><f:mi>R</f:mi><f:mn>0</f:mn></f:msub></f:math> is the resistance at zero field) are proportional to the temperature. The DW resistivity is calculated to be of the order of <g:math xmlns:g="http://www.w3.org/1998/Math/MathML"><g:mrow><g:msup><g:mn>10</g:mn><g:mrow><g:mo>−</g:mo><g:mn>17</g:mn></g:mrow></g:msup><g:mspace width="0.16em"/><g:mi mathvariant="normal">Ω</g:mi><g:mspace width="0.16em"/><g:msup><g:mrow><g:mi mathvariant="normal">m</g:mi></g:mrow><g:mn>2</g:mn></g:msup></g:mrow></g:math> at 10 K and <l:math xmlns:l="http://www.w3.org/1998/Math/MathML"><l:mrow><l:msup><l:mn>10</l:mn><l:mrow><l:mo>−</l:mo><l:mn>15</l:mn></l:mrow></l:msup><l:mspace width="0.16em"/><l:mi mathvariant="normal">Ω</l:mi><l:mspace width="0.16em"/><l:msup><l:mrow><l:mi mathvariant="normal">m</l:mi></l:mrow><l:mn>2</l:mn></l:msup></l:mrow></l:math> at 300 K. The latter value agrees with the reported intrinsic DW resistivity in films. In addition, we find approximately constant <q:math xmlns:q="http://www.w3.org/1998/Math/MathML"><q:mrow><q:mi mathvariant="normal">Δ</q:mi><q:mi>R</q:mi></q:mrow></q:math> and <s:math xmlns:s="http://www.w3.org/1998/Math/MathML"><s:mrow><s:mi mathvariant="normal">Δ</s:mi><s:mi>R</s:mi><s:mo>/</s:mo><s:msub><s:mi>R</s:mi><s:mn>0</s:mn></s:msub></s:mrow></s:math> for widths from 5 down to <u:math xmlns:u="http://www.w3.org/1998/Math/MathML"><u:mrow><u:mn>1.8</u:mn><u:mspace width="0.16em"/><u:mi>µ</u:mi><u:mi mathvariant="normal">m</u:mi></u:mrow></u:math> and a pronounced increase in both quantities when the width goes down to 755 nm. With the extracted magnetocrystalline anisotropy parameters from the measurements of the remanent magnetization and the magnetic torque as function of angle of the magnetic field with respect to the substrate normal, we further perform micromagnetic simulations and obtain results consistent with the experimental data. Our work may promote designing relevant prototypes and may constitute a platform to explore the effect of spin torque transfer on DWs.
Authors
- Harm A. Bakker
- Léon Abelmann (ORCID: https://orcid.org/0000-0002-9733-1230)
- J. Aarts (ORCID: https://orcid.org/0000-0002-4113-0835)
- Junxiang Yao (ORCID: https://orcid.org/0000-0002-3496-6263)
- Maurits E. K. Geenen
Institutions
- Leiden University (NL)
- University of Twente (NL)
Publication Details
- Journal
- Physical Review Materials
- Published
- 2025-08-26
- DOI
- https://doi.org/10.1103/np4m-j4b7
- Primary Topic
- Magnetic and transport properties of perovskites and related materials
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- European Cooperation in Science and Technology
- Nederlandse Organisatie voor Wetenschappelijk Onderzoek
- China Scholarship Council