On coherent states and the Self-Consistent Harmonic Approximation
Autor(a) principal: | |
---|---|
Data de Publicação: | 2019 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | LOCUS Repositório Institucional da UFV |
Texto Completo: | https://doi.org/10.1016/j.jmmm.2018.09.122 http://www.locus.ufv.br/handle/123456789/23656 |
Resumo: | We used the Self-Consistent Harmonic Approximation (SCHA) to study the thermodynamics of the precession magnetization in a two-dimensional isotropic ferromagnet. The SCHA treats the Hamiltonian in terms of the canonically conjugate operators Sz and φ (the azimuth angle) including renormalized temperature dependent parameters to take into account higher order interactions. It is well-known that in right conditions, a dynamic magnetic field is able to provide spin pumping and drives the system to a magnon Bose-Einstein condensation. The magnon condensate is a coherent state that presents minimal uncertainty for the Sz and φ operators. Consequently, 〈Sz〉 and 〈φ〉 should constitute natural fields to describe the model, which justifies the SCHA formalism. The results obtained are consistent with other theoretical and experimental works. |
id |
UFV_1b839b8ba32daf3e3f5c08995f201850 |
---|---|
oai_identifier_str |
oai:locus.ufv.br:123456789/23656 |
network_acronym_str |
UFV |
network_name_str |
LOCUS Repositório Institucional da UFV |
repository_id_str |
2145 |
spelling |
Moura, A. R.Lopes, R. J. C.2019-02-22T11:07:23Z2019-02-22T11:07:23Z2019-02-150304-8853https://doi.org/10.1016/j.jmmm.2018.09.122http://www.locus.ufv.br/handle/123456789/23656We used the Self-Consistent Harmonic Approximation (SCHA) to study the thermodynamics of the precession magnetization in a two-dimensional isotropic ferromagnet. The SCHA treats the Hamiltonian in terms of the canonically conjugate operators Sz and φ (the azimuth angle) including renormalized temperature dependent parameters to take into account higher order interactions. It is well-known that in right conditions, a dynamic magnetic field is able to provide spin pumping and drives the system to a magnon Bose-Einstein condensation. The magnon condensate is a coherent state that presents minimal uncertainty for the Sz and φ operators. Consequently, 〈Sz〉 and 〈φ〉 should constitute natural fields to describe the model, which justifies the SCHA formalism. The results obtained are consistent with other theoretical and experimental works.engJournal of Magnetism and Magnetic MaterialsVolume 472, Pages 1- 6, February 20192018 Elsevier B.V. All rights reserved.info:eu-repo/semantics/openAccessFerromagnetismCoherent statesSelf-Consistent Harmonic ApproximationPrecession magnetizationOn coherent states and the Self-Consistent Harmonic Approximationinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfreponame:LOCUS Repositório Institucional da UFVinstname:Universidade Federal de Viçosa (UFV)instacron:UFVORIGINALartigo.pdfartigo.pdfTexto completoapplication/pdf734314https://locus.ufv.br//bitstream/123456789/23656/1/artigo.pdf766adfa3ea3bb699989b7c1795af76a8MD51LICENSElicense.txtlicense.txttext/plain; charset=utf-81748https://locus.ufv.br//bitstream/123456789/23656/2/license.txt8a4605be74aa9ea9d79846c1fba20a33MD52123456789/236562019-02-22 08:25:42.334oai:locus.ufv.br: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Repositório InstitucionalPUBhttps://www.locus.ufv.br/oai/requestfabiojreis@ufv.bropendoar:21452019-02-22T11:25:42LOCUS Repositório Institucional da UFV - Universidade Federal de Viçosa (UFV)false |
dc.title.en.fl_str_mv |
On coherent states and the Self-Consistent Harmonic Approximation |
title |
On coherent states and the Self-Consistent Harmonic Approximation |
spellingShingle |
On coherent states and the Self-Consistent Harmonic Approximation Moura, A. R. Ferromagnetism Coherent states Self-Consistent Harmonic Approximation Precession magnetization |
title_short |
On coherent states and the Self-Consistent Harmonic Approximation |
title_full |
On coherent states and the Self-Consistent Harmonic Approximation |
title_fullStr |
On coherent states and the Self-Consistent Harmonic Approximation |
title_full_unstemmed |
On coherent states and the Self-Consistent Harmonic Approximation |
title_sort |
On coherent states and the Self-Consistent Harmonic Approximation |
author |
Moura, A. R. |
author_facet |
Moura, A. R. Lopes, R. J. C. |
author_role |
author |
author2 |
Lopes, R. J. C. |
author2_role |
author |
dc.contributor.author.fl_str_mv |
Moura, A. R. Lopes, R. J. C. |
dc.subject.pt-BR.fl_str_mv |
Ferromagnetism Coherent states Self-Consistent Harmonic Approximation Precession magnetization |
topic |
Ferromagnetism Coherent states Self-Consistent Harmonic Approximation Precession magnetization |
description |
We used the Self-Consistent Harmonic Approximation (SCHA) to study the thermodynamics of the precession magnetization in a two-dimensional isotropic ferromagnet. The SCHA treats the Hamiltonian in terms of the canonically conjugate operators Sz and φ (the azimuth angle) including renormalized temperature dependent parameters to take into account higher order interactions. It is well-known that in right conditions, a dynamic magnetic field is able to provide spin pumping and drives the system to a magnon Bose-Einstein condensation. The magnon condensate is a coherent state that presents minimal uncertainty for the Sz and φ operators. Consequently, 〈Sz〉 and 〈φ〉 should constitute natural fields to describe the model, which justifies the SCHA formalism. The results obtained are consistent with other theoretical and experimental works. |
publishDate |
2019 |
dc.date.accessioned.fl_str_mv |
2019-02-22T11:07:23Z |
dc.date.available.fl_str_mv |
2019-02-22T11:07:23Z |
dc.date.issued.fl_str_mv |
2019-02-15 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://doi.org/10.1016/j.jmmm.2018.09.122 http://www.locus.ufv.br/handle/123456789/23656 |
dc.identifier.issn.none.fl_str_mv |
0304-8853 |
identifier_str_mv |
0304-8853 |
url |
https://doi.org/10.1016/j.jmmm.2018.09.122 http://www.locus.ufv.br/handle/123456789/23656 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.ispartofseries.pt-BR.fl_str_mv |
Volume 472, Pages 1- 6, February 2019 |
dc.rights.driver.fl_str_mv |
2018 Elsevier B.V. All rights reserved. info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
2018 Elsevier B.V. All rights reserved. |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Journal of Magnetism and Magnetic Materials |
publisher.none.fl_str_mv |
Journal of Magnetism and Magnetic Materials |
dc.source.none.fl_str_mv |
reponame:LOCUS Repositório Institucional da UFV instname:Universidade Federal de Viçosa (UFV) instacron:UFV |
instname_str |
Universidade Federal de Viçosa (UFV) |
instacron_str |
UFV |
institution |
UFV |
reponame_str |
LOCUS Repositório Institucional da UFV |
collection |
LOCUS Repositório Institucional da UFV |
bitstream.url.fl_str_mv |
https://locus.ufv.br//bitstream/123456789/23656/1/artigo.pdf https://locus.ufv.br//bitstream/123456789/23656/2/license.txt |
bitstream.checksum.fl_str_mv |
766adfa3ea3bb699989b7c1795af76a8 8a4605be74aa9ea9d79846c1fba20a33 |
bitstream.checksumAlgorithm.fl_str_mv |
MD5 MD5 |
repository.name.fl_str_mv |
LOCUS Repositório Institucional da UFV - Universidade Federal de Viçosa (UFV) |
repository.mail.fl_str_mv |
fabiojreis@ufv.br |
_version_ |
1801213103948431360 |