Impurity-induced triple point fermions in twisted bilayer graphene
Autor(a) principal: | |
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Data de Publicação: | 2019 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1103/PhysRevB.99.245118 http://hdl.handle.net/11449/185779 |
Resumo: | Triple point fermions are elusive electronic excitations that generalize Dirac and Weyl modes beyond the conventional high-energy paradigm. Yet, finding real materials naturally hosting these excitations at the Fermi energy has remained challenging. Here we show that twisted bilayer graphene is a versatile platform to realize robust triple point fermions in two dimensions. In particular, we establish that the introduction of localized impurities lifts one of the two degenerate Dirac cones, yielding triple point fermions at charge neutrality. Furthermore, we show that the valley polarization is preserved for certain impurity locations in the Moire supercell for both weak and strong impurity potentials. We finally show that in the presence of interactions, a symmetry-broken state with local magnetization can develop out of the triple point bands, which can be selectively controlled by electrostatic gating. Our results put forward twisted bilayer graphene as a simple solid-state platform to realize triple point fermions at charge neutrality and demonstrate the nontrivial role of impurities in Moire systems. |
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Impurity-induced triple point fermions in twisted bilayer grapheneTriple point fermions are elusive electronic excitations that generalize Dirac and Weyl modes beyond the conventional high-energy paradigm. Yet, finding real materials naturally hosting these excitations at the Fermi energy has remained challenging. Here we show that twisted bilayer graphene is a versatile platform to realize robust triple point fermions in two dimensions. In particular, we establish that the introduction of localized impurities lifts one of the two degenerate Dirac cones, yielding triple point fermions at charge neutrality. Furthermore, we show that the valley polarization is preserved for certain impurity locations in the Moire supercell for both weak and strong impurity potentials. We finally show that in the presence of interactions, a symmetry-broken state with local magnetization can develop out of the triple point bands, which can be selectively controlled by electrostatic gating. Our results put forward twisted bilayer graphene as a simple solid-state platform to realize triple point fermions at charge neutrality and demonstrate the nontrivial role of impurities in Moire systems.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação para o Desenvolvimento da UNESP (FUNDUNESP)ETH Fellowship programJSPS Core-to-Core program Oxide Superspin international networkSouth Amer Inst Fundamental Res, Int Ctr Theoret Phys, BR-01140070 Sao Paulo, SP, BrazilUniv Estadual Paulista, Inst Fis Teor, BR-01140070 Sao Paulo, SP, BrazilSwiss Fed Inst Technol, Inst Theoret Phys, CH-8093 Zurich, SwitzerlandUniv Estadual Paulista, Inst Fis Teor, BR-01140070 Sao Paulo, SP, BrazilFAPESP: 2018/04955-9FUNDUNESP: 2338-2014 CCPFAPESP: 2018/18287-8Amer Physical SocSouth Amer Inst Fundamental ResUniversidade Estadual Paulista (Unesp)Swiss Fed Inst TechnolRamires, Aline [UNESP]Lado, Jose L.2019-10-04T12:38:23Z2019-10-04T12:38:23Z2019-06-10info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article7http://dx.doi.org/10.1103/PhysRevB.99.245118Physical Review B. College Pk: Amer Physical Soc, v. 99, n. 24, 7 p., 2019.2469-9950http://hdl.handle.net/11449/18577910.1103/PhysRevB.99.245118WOS:000470840800005Web of Sciencereponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengPhysical Review Binfo:eu-repo/semantics/openAccess2021-10-23T01:35:41Zoai:repositorio.unesp.br:11449/185779Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T21:14:36.820292Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Impurity-induced triple point fermions in twisted bilayer graphene |
title |
Impurity-induced triple point fermions in twisted bilayer graphene |
spellingShingle |
Impurity-induced triple point fermions in twisted bilayer graphene Ramires, Aline [UNESP] |
title_short |
Impurity-induced triple point fermions in twisted bilayer graphene |
title_full |
Impurity-induced triple point fermions in twisted bilayer graphene |
title_fullStr |
Impurity-induced triple point fermions in twisted bilayer graphene |
title_full_unstemmed |
Impurity-induced triple point fermions in twisted bilayer graphene |
title_sort |
Impurity-induced triple point fermions in twisted bilayer graphene |
author |
Ramires, Aline [UNESP] |
author_facet |
Ramires, Aline [UNESP] Lado, Jose L. |
author_role |
author |
author2 |
Lado, Jose L. |
author2_role |
author |
dc.contributor.none.fl_str_mv |
South Amer Inst Fundamental Res Universidade Estadual Paulista (Unesp) Swiss Fed Inst Technol |
dc.contributor.author.fl_str_mv |
Ramires, Aline [UNESP] Lado, Jose L. |
description |
Triple point fermions are elusive electronic excitations that generalize Dirac and Weyl modes beyond the conventional high-energy paradigm. Yet, finding real materials naturally hosting these excitations at the Fermi energy has remained challenging. Here we show that twisted bilayer graphene is a versatile platform to realize robust triple point fermions in two dimensions. In particular, we establish that the introduction of localized impurities lifts one of the two degenerate Dirac cones, yielding triple point fermions at charge neutrality. Furthermore, we show that the valley polarization is preserved for certain impurity locations in the Moire supercell for both weak and strong impurity potentials. We finally show that in the presence of interactions, a symmetry-broken state with local magnetization can develop out of the triple point bands, which can be selectively controlled by electrostatic gating. Our results put forward twisted bilayer graphene as a simple solid-state platform to realize triple point fermions at charge neutrality and demonstrate the nontrivial role of impurities in Moire systems. |
publishDate |
2019 |
dc.date.none.fl_str_mv |
2019-10-04T12:38:23Z 2019-10-04T12:38:23Z 2019-06-10 |
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 |
http://dx.doi.org/10.1103/PhysRevB.99.245118 Physical Review B. College Pk: Amer Physical Soc, v. 99, n. 24, 7 p., 2019. 2469-9950 http://hdl.handle.net/11449/185779 10.1103/PhysRevB.99.245118 WOS:000470840800005 |
url |
http://dx.doi.org/10.1103/PhysRevB.99.245118 http://hdl.handle.net/11449/185779 |
identifier_str_mv |
Physical Review B. College Pk: Amer Physical Soc, v. 99, n. 24, 7 p., 2019. 2469-9950 10.1103/PhysRevB.99.245118 WOS:000470840800005 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Physical Review B |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
7 |
dc.publisher.none.fl_str_mv |
Amer Physical Soc |
publisher.none.fl_str_mv |
Amer Physical Soc |
dc.source.none.fl_str_mv |
Web of Science reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1808129300404109312 |