Spin Transport and Magnetization Dynamics in Various Magnetic Systems

Persistent Link:
http://hdl.handle.net/10150/333352
Title:
Spin Transport and Magnetization Dynamics in Various Magnetic Systems
Author:
Zhang, Shulei
Issue Date:
2014
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Embargo:
Release 30-Aug-2017
Abstract:
The general theme of the thesis is the interplay between magnetization dynamics and spin transport. The main presentation is divided into three parts. The first part is devoted to deepening our understanding on magnetic damping of ferromagnetic metals, which is one of the long-standing issues in conventional spintronics that has not been completely understood. For a nonuniformly-magnetized ferromagnetic metal, we find that the damping is nonlocal and is enhanced as compared to that in the uniform case. It is therefore necessary to generalize the conventional Landau-Lifshitz-Gilbert equation to include the additional damping. In a different vein, the decay mechanism of the uniform precession mode has been investigated. We point out the important role of spin-conserving electron-magnon interaction in the relaxation process by quantitatively examining its contribution to the ferromagnetic resonance linewidth. In the second part, a transport theory is developed for magnons which, in addition to conduction electrons, can also carry and propagate spin angular momentum via the magnon current. We demonstrate that the mutual conversion of magnon current and spin current may take place at magnetic interfaces. We also predict a novel magnon-mediated electric drag effect in a metal/magnetic-insulator/metal trilayer structure. This study may pave the way to the new area of insulator-based spintronics. In the third part of thesis, particular attention is paid to the influence the spin orbit coupling on both charge and spin transport. We theoretically investigate magnetotransport anisotropy and the conversion relations of spin and charge currents in various magnetic systems, and apply our results to interpret recent experiments.
Type:
text; Electronic Dissertation
Keywords:
magnetization dynamics; magnon transport; spin orbit coupling; spin transport; Physics; magnetic damping
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Physics
Degree Grantor:
University of Arizona
Advisor:
Zhang, Shufeng

Full metadata record

DC FieldValue Language
dc.language.isoen_USen
dc.titleSpin Transport and Magnetization Dynamics in Various Magnetic Systemsen_US
dc.creatorZhang, Shuleien_US
dc.contributor.authorZhang, Shuleien_US
dc.date.issued2014en
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.releaseRelease 30-Aug-2017en_US
dc.description.abstractThe general theme of the thesis is the interplay between magnetization dynamics and spin transport. The main presentation is divided into three parts. The first part is devoted to deepening our understanding on magnetic damping of ferromagnetic metals, which is one of the long-standing issues in conventional spintronics that has not been completely understood. For a nonuniformly-magnetized ferromagnetic metal, we find that the damping is nonlocal and is enhanced as compared to that in the uniform case. It is therefore necessary to generalize the conventional Landau-Lifshitz-Gilbert equation to include the additional damping. In a different vein, the decay mechanism of the uniform precession mode has been investigated. We point out the important role of spin-conserving electron-magnon interaction in the relaxation process by quantitatively examining its contribution to the ferromagnetic resonance linewidth. In the second part, a transport theory is developed for magnons which, in addition to conduction electrons, can also carry and propagate spin angular momentum via the magnon current. We demonstrate that the mutual conversion of magnon current and spin current may take place at magnetic interfaces. We also predict a novel magnon-mediated electric drag effect in a metal/magnetic-insulator/metal trilayer structure. This study may pave the way to the new area of insulator-based spintronics. In the third part of thesis, particular attention is paid to the influence the spin orbit coupling on both charge and spin transport. We theoretically investigate magnetotransport anisotropy and the conversion relations of spin and charge currents in various magnetic systems, and apply our results to interpret recent experiments.en_US
dc.typetexten
dc.typeElectronic Dissertationen
dc.subjectmagnetization dynamicsen_US
dc.subjectmagnon transporten_US
dc.subjectspin orbit couplingen_US
dc.subjectspin transporten_US
dc.subjectPhysicsen_US
dc.subjectmagnetic dampingen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplinePhysicsen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorZhang, Shufengen_US
dc.contributor.committeememberWang, Weigangen_US
dc.contributor.committeememberLeRoy, Brianen_US
dc.contributor.committeememberMazumdar, Sumiten_US
dc.contributor.committeememberStafford, Charlesen_US
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