Unveiling domain wall dynamics of ferrimagnets in thermal magnon currents : competition of angular momentum transfer and entropic torque
Unveiling domain wall dynamics of ferrimagnets in thermal magnon currents : competition of angular momentum transfer and entropic torque
Loading...
Date
2020
Editors
Journal ISSN
Electronic ISSN
ISBN
Bibliographical data
Publisher
Series
URI (citable link)
DOI (citable link)
ArXiv-ID
International patent number
Link to the license
EU project number
Project
Open Access publication
Collections
Title in another language
Publication type
Journal article
Publication status
Published
Published in
Physical Review Research ; 2 (2020), 1. - 013293. - American Physical Society (APS). - eISSN 2643-1564
Abstract
Control of magnetic domain wall motion holds promise for efficient manipulation and transfer of magnetically stored information. Thermal magnon currents, generated by temperature gradients, can be used to move magnetic textures, from domain walls to magnetic vortices and skyrmions. In the past several years, theoretical studies have focused on ferro- and antiferromagnetic spin structures, where domain walls always move toward the hotter end of the thermal gradient. Here we perform numerical studies using atomistic spin dynamics simulations and complementary analytical calculations to derive an equation of motion for the domain wall velocity in ferrimagnets. We demonstrate that in ferrimagnets, domain wall motion under thermal magnon currents shows a much richer dynamics. Below the Walker breakdown, we find that the temperature gradient always pulls the domain wall toward the hot end by minimizing its free energy, in agreement with the observations for ferro- and antiferromagnets in the same regime. Above Walker breakdown, the ferrimagnetic domain wall can show the opposite, counterintuitive behavior of moving toward the cold end. We show that in this case, the motion to the hotter or the colder ends is driven by angular momentum transfer and therefore strongly related to the angular momentum compensation temperature, a unique property of ferrimagnets where the intrinsic angular momentum of the ferrimagnet is zero while the sublattice angular momentum remains finite. In particular, we find that below the compensation temperature the wall moves toward the cold end, whereas above it toward the hot end. Moreover, we find that for ferrimagnets, there is a torque compensation temperature at which the domain wall dynamics shows similar characteristics to antiferromagnets, that is, quasi-inertia-free motion and the absence of Walker breakdown. This finding opens the door for fast control of magnetic domains as given by the antiferromagnetic character while conserving the advantage of ferromagnets in terms of measuring and control by conventional means such as magnetic fields.
Summary in another language
Subject (DDC)
530 Physics
Keywords
Conference
Review
undefined / . - undefined, undefined. - (undefined; undefined)
Cite This
ISO 690
DONGES, Andreas, Niklas GRIMM, Florian JAKOBS, Severin SELZER, Ulrike RITZMANN, Unai ATXITIA, Ulrich NOWAK, 2020. Unveiling domain wall dynamics of ferrimagnets in thermal magnon currents : competition of angular momentum transfer and entropic torque. In: Physical Review Research. American Physical Society (APS). 2(1), 013293. eISSN 2643-1564. Available under: doi: 10.1103/PhysRevResearch.2.013293BibTex
@article{Donges2020Unvei-51065, year={2020}, doi={10.1103/PhysRevResearch.2.013293}, title={Unveiling domain wall dynamics of ferrimagnets in thermal magnon currents : competition of angular momentum transfer and entropic torque}, number={1}, volume={2}, journal={Physical Review Research}, author={Donges, Andreas and Grimm, Niklas and Jakobs, Florian and Selzer, Severin and Ritzmann, Ulrike and Atxitia, Unai and Nowak, Ulrich}, note={Article Number: 013293} }
RDF
<rdf:RDF xmlns:dcterms="http://purl.org/dc/terms/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:bibo="http://purl.org/ontology/bibo/" xmlns:dspace="http://digital-repositories.org/ontologies/dspace/0.1.0#" xmlns:foaf="http://xmlns.com/foaf/0.1/" xmlns:void="http://rdfs.org/ns/void#" xmlns:xsd="http://www.w3.org/2001/XMLSchema#" > <rdf:Description rdf:about="https://kops.uni-konstanz.de/server/rdf/resource/123456789/51065"> <dc:contributor>Selzer, Severin</dc:contributor> <dc:creator>Grimm, Niklas</dc:creator> <dc:contributor>Jakobs, Florian</dc:contributor> <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/41"/> <dcterms:abstract xml:lang="eng">Control of magnetic domain wall motion holds promise for efficient manipulation and transfer of magnetically stored information. Thermal magnon currents, generated by temperature gradients, can be used to move magnetic textures, from domain walls to magnetic vortices and skyrmions. In the past several years, theoretical studies have focused on ferro- and antiferromagnetic spin structures, where domain walls always move toward the hotter end of the thermal gradient. Here we perform numerical studies using atomistic spin dynamics simulations and complementary analytical calculations to derive an equation of motion for the domain wall velocity in ferrimagnets. We demonstrate that in ferrimagnets, domain wall motion under thermal magnon currents shows a much richer dynamics. Below the Walker breakdown, we find that the temperature gradient always pulls the domain wall toward the hot end by minimizing its free energy, in agreement with the observations for ferro- and antiferromagnets in the same regime. Above Walker breakdown, the ferrimagnetic domain wall can show the opposite, counterintuitive behavior of moving toward the cold end. We show that in this case, the motion to the hotter or the colder ends is driven by angular momentum transfer and therefore strongly related to the angular momentum compensation temperature, a unique property of ferrimagnets where the intrinsic angular momentum of the ferrimagnet is zero while the sublattice angular momentum remains finite. In particular, we find that below the compensation temperature the wall moves toward the cold end, whereas above it toward the hot end. Moreover, we find that for ferrimagnets, there is a torque compensation temperature at which the domain wall dynamics shows similar characteristics to antiferromagnets, that is, quasi-inertia-free motion and the absence of Walker breakdown. This finding opens the door for fast control of magnetic domains as given by the antiferromagnetic character while conserving the advantage of ferromagnets in terms of measuring and control by conventional means such as magnetic fields.</dcterms:abstract> <dcterms:rights rdf:resource="http://creativecommons.org/licenses/by/4.0/"/> <dspace:hasBitstream rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/51065/1/Donges_2-1av9cz4ld1hu92.pdf"/> <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/41"/> <foaf:homepage rdf:resource="http://localhost:8080/"/> <dcterms:issued>2020</dcterms:issued> <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2020-09-28T14:12:13Z</dc:date> <dcterms:hasPart rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/51065/1/Donges_2-1av9cz4ld1hu92.pdf"/> <dc:contributor>Donges, Andreas</dc:contributor> <dc:language>eng</dc:language> <dc:contributor>Atxitia, Unai</dc:contributor> <dc:creator>Nowak, Ulrich</dc:creator> <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2020-09-28T14:12:13Z</dcterms:available> <dc:creator>Donges, Andreas</dc:creator> <dc:creator>Ritzmann, Ulrike</dc:creator> <dc:creator>Atxitia, Unai</dc:creator> <dc:rights>Attribution 4.0 International</dc:rights> <dc:contributor>Nowak, Ulrich</dc:contributor> <dc:creator>Jakobs, Florian</dc:creator> <bibo:uri rdf:resource="https://kops.uni-konstanz.de/handle/123456789/51065"/> <dc:creator>Selzer, Severin</dc:creator> <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/> <dc:contributor>Ritzmann, Ulrike</dc:contributor> <dc:contributor>Grimm, Niklas</dc:contributor> <dcterms:title>Unveiling domain wall dynamics of ferrimagnets in thermal magnon currents : competition of angular momentum transfer and entropic torque</dcterms:title> </rdf:Description> </rdf:RDF>
Internal note
xmlui.Submission.submit.DescribeStep.inputForms.label.kops_note_fromSubmitter
Examination date of dissertation
Method of financing
Comment on publication
Alliance license
Corresponding Authors der Uni Konstanz vorhanden
International Co-Authors
Bibliography of Konstanz
Yes
Refereed
Yes