Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field

Autores
Ghioldi, Esteban Agustín; Gonzalez, Matías Gabriel; Zhang, Shang Shun; Kamiya, Yoshitomo; Manuel, Luis Oscar; Trumper, Adolfo Emilio; Batista, Cristian D.
Año de publicación
2018
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
We compute the zero-temperature dynamical structure factor S(q,ω) of the triangular lattice Heisenberg model (TLHM) using a Schwinger boson approach that includes the Gaussian fluctuations (1/N corrections) of the saddle-point solution. While the ground state of this model exhibits a well-known 120 -magnetic ordering, experimental observations have revealed a strong quantum character of the excitation spectrum. We conjecture that this phenomenon arises from the proximity of the ground state of the TLHM to the quantum melting point separating the magnetically ordered and spin-liquid states. Within this scenario, magnons are described as collective modes (two-spinon bound states) of a spinon condensate (Higgs phase) that spontaneously break the SU(2) symmetry of the TLHM. Crucial to our results is the proper account of this spontaneous symmetry breaking. The main qualitative difference relative to semiclassical treatments (1/S expansion) is the presence of a high-energy spinon continuum extending up to about three times the single-magnon bandwidth. In addition, the magnitude of the ordered moment (m=0.224) agrees very well with numerical results and the low-energy part of the single-magnon dispersion is in very good agreement with series expansions. Our results indicate that the Schwinger boson approach is an adequate starting point for describing the excitation spectrum of some magnetically ordered compounds that are near the quantum melting point separating this Higgs phase from the deconfined spin-liquid state.
Fil: Ghioldi, Esteban Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Gonzalez, Matías Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Zhang, Shang Shun. University of Tennessee; Estados Unidos
Fil: Kamiya, Yoshitomo. RIKEN; Japón
Fil: Manuel, Luis Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Trumper, Adolfo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Batista, Cristian D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Materia
MAGNETIC FRUSTRATION
NEUTRON SCATTERING
SPINON
TRIANGULAR HEISENBERG MODEL
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/88511
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/88511
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean fieldGhioldi, Esteban AgustínGonzalez, Matías GabrielZhang, Shang ShunKamiya, YoshitomoManuel, Luis OscarTrumper, Adolfo EmilioBatista, Cristian D.MAGNETIC FRUSTRATIONNEUTRON SCATTERINGSPINONTRIANGULAR HEISENBERG MODELhttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1We compute the zero-temperature dynamical structure factor S(q,ω) of the triangular lattice Heisenberg model (TLHM) using a Schwinger boson approach that includes the Gaussian fluctuations (1/N corrections) of the saddle-point solution. While the ground state of this model exhibits a well-known 120 -magnetic ordering, experimental observations have revealed a strong quantum character of the excitation spectrum. We conjecture that this phenomenon arises from the proximity of the ground state of the TLHM to the quantum melting point separating the magnetically ordered and spin-liquid states. Within this scenario, magnons are described as collective modes (two-spinon bound states) of a spinon condensate (Higgs phase) that spontaneously break the SU(2) symmetry of the TLHM. Crucial to our results is the proper account of this spontaneous symmetry breaking. The main qualitative difference relative to semiclassical treatments (1/S expansion) is the presence of a high-energy spinon continuum extending up to about three times the single-magnon bandwidth. In addition, the magnitude of the ordered moment (m=0.224) agrees very well with numerical results and the low-energy part of the single-magnon dispersion is in very good agreement with series expansions. Our results indicate that the Schwinger boson approach is an adequate starting point for describing the excitation spectrum of some magnetically ordered compounds that are near the quantum melting point separating this Higgs phase from the deconfined spin-liquid state.Fil: Ghioldi, Esteban Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Gonzalez, Matías Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Zhang, Shang Shun. University of Tennessee; Estados UnidosFil: Kamiya, Yoshitomo. RIKEN; JapónFil: Manuel, Luis Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Trumper, Adolfo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Batista, Cristian D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaAmerican Physical Society2018-11info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/88511Ghioldi, Esteban Agustín; Gonzalez, Matías Gabriel; Zhang, Shang Shun; Kamiya, Yoshitomo; Manuel, Luis Oscar; et al.; Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field; American Physical Society; Physical Review B; 98; 18; 11-2018; 1-23; 1844032469-9950CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://link.aps.org/doi/10.1103/PhysRevB.98.184403info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevB.98.184403info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T09:36:19Zoai:ri.conicet.gov.ar:11336/88511instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 09:36:20.034CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
title Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
spellingShingle Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
Ghioldi, Esteban Agustín
MAGNETIC FRUSTRATION
NEUTRON SCATTERING
SPINON
TRIANGULAR HEISENBERG MODEL
title_short Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
title_full Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
title_fullStr Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
title_full_unstemmed Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
title_sort Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field
dc.creator.none.fl_str_mv Ghioldi, Esteban Agustín
Gonzalez, Matías Gabriel
Zhang, Shang Shun
Kamiya, Yoshitomo
Manuel, Luis Oscar
Trumper, Adolfo Emilio
Batista, Cristian D.
author Ghioldi, Esteban Agustín
author_facet Ghioldi, Esteban Agustín
Gonzalez, Matías Gabriel
Zhang, Shang Shun
Kamiya, Yoshitomo
Manuel, Luis Oscar
Trumper, Adolfo Emilio
Batista, Cristian D.
author_role author
author2 Gonzalez, Matías Gabriel
Zhang, Shang Shun
Kamiya, Yoshitomo
Manuel, Luis Oscar
Trumper, Adolfo Emilio
Batista, Cristian D.
author2_role author
author
author
author
author
author
dc.subject.none.fl_str_mv MAGNETIC FRUSTRATION
NEUTRON SCATTERING
SPINON
TRIANGULAR HEISENBERG MODEL
topic MAGNETIC FRUSTRATION
NEUTRON SCATTERING
SPINON
TRIANGULAR HEISENBERG MODEL
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv We compute the zero-temperature dynamical structure factor S(q,ω) of the triangular lattice Heisenberg model (TLHM) using a Schwinger boson approach that includes the Gaussian fluctuations (1/N corrections) of the saddle-point solution. While the ground state of this model exhibits a well-known 120 -magnetic ordering, experimental observations have revealed a strong quantum character of the excitation spectrum. We conjecture that this phenomenon arises from the proximity of the ground state of the TLHM to the quantum melting point separating the magnetically ordered and spin-liquid states. Within this scenario, magnons are described as collective modes (two-spinon bound states) of a spinon condensate (Higgs phase) that spontaneously break the SU(2) symmetry of the TLHM. Crucial to our results is the proper account of this spontaneous symmetry breaking. The main qualitative difference relative to semiclassical treatments (1/S expansion) is the presence of a high-energy spinon continuum extending up to about three times the single-magnon bandwidth. In addition, the magnitude of the ordered moment (m=0.224) agrees very well with numerical results and the low-energy part of the single-magnon dispersion is in very good agreement with series expansions. Our results indicate that the Schwinger boson approach is an adequate starting point for describing the excitation spectrum of some magnetically ordered compounds that are near the quantum melting point separating this Higgs phase from the deconfined spin-liquid state.
Fil: Ghioldi, Esteban Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Gonzalez, Matías Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Zhang, Shang Shun. University of Tennessee; Estados Unidos
Fil: Kamiya, Yoshitomo. RIKEN; Japón
Fil: Manuel, Luis Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Trumper, Adolfo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
Fil: Batista, Cristian D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
description We compute the zero-temperature dynamical structure factor S(q,ω) of the triangular lattice Heisenberg model (TLHM) using a Schwinger boson approach that includes the Gaussian fluctuations (1/N corrections) of the saddle-point solution. While the ground state of this model exhibits a well-known 120 -magnetic ordering, experimental observations have revealed a strong quantum character of the excitation spectrum. We conjecture that this phenomenon arises from the proximity of the ground state of the TLHM to the quantum melting point separating the magnetically ordered and spin-liquid states. Within this scenario, magnons are described as collective modes (two-spinon bound states) of a spinon condensate (Higgs phase) that spontaneously break the SU(2) symmetry of the TLHM. Crucial to our results is the proper account of this spontaneous symmetry breaking. The main qualitative difference relative to semiclassical treatments (1/S expansion) is the presence of a high-energy spinon continuum extending up to about three times the single-magnon bandwidth. In addition, the magnitude of the ordered moment (m=0.224) agrees very well with numerical results and the low-energy part of the single-magnon dispersion is in very good agreement with series expansions. Our results indicate that the Schwinger boson approach is an adequate starting point for describing the excitation spectrum of some magnetically ordered compounds that are near the quantum melting point separating this Higgs phase from the deconfined spin-liquid state.
publishDate 2018
dc.date.none.fl_str_mv 2018-11
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/88511
Ghioldi, Esteban Agustín; Gonzalez, Matías Gabriel; Zhang, Shang Shun; Kamiya, Yoshitomo; Manuel, Luis Oscar; et al.; Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field; American Physical Society; Physical Review B; 98; 18; 11-2018; 1-23; 184403
2469-9950
CONICET Digital
CONICET
url http://hdl.handle.net/11336/88511
identifier_str_mv Ghioldi, Esteban Agustín; Gonzalez, Matías Gabriel; Zhang, Shang Shun; Kamiya, Yoshitomo; Manuel, Luis Oscar; et al.; Dynamical structure factor of the triangular antiferromagnet: Schwinger boson theory beyond mean field; American Physical Society; Physical Review B; 98; 18; 11-2018; 1-23; 184403
2469-9950
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://link.aps.org/doi/10.1103/PhysRevB.98.184403
info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevB.98.184403
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv American Physical Society
publisher.none.fl_str_mv American Physical Society
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 13.070432

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