Acoustic spin-Chern insulator induced by synthetic spin-orbit coupling with spin conservation breaking.
Journal
Nature communications
ISSN: 2041-1723
Titre abrégé: Nat Commun
Pays: England
ID NLM: 101528555
Informations de publication
Date de publication:
26 Jun 2020
26 Jun 2020
Historique:
received:
05
05
2020
accepted:
05
06
2020
entrez:
28
6
2020
pubmed:
28
6
2020
medline:
28
6
2020
Statut:
epublish
Résumé
Topologically protected surface modes of classical waves hold the promise to enable a variety of applications ranging from robust transport of energy to reliable information processing networks. However, both the route of implementing an analogue of the quantum Hall effect as well as the quantum spin Hall effect are obstructed for acoustics by the requirement of a magnetic field, or the presence of fermionic quantum statistics, respectively. Here, we construct a two-dimensional topological acoustic crystal induced by the synthetic spin-orbit coupling, a crucial ingredient of topological insulators, with spin non-conservation. Our setup allows us to free ourselves of symmetry constraints as we rely on the concept of a non-vanishing "spin" Chern number. We experimentally characterize the emerging boundary states which we show to be gapless and helical. More importantly, we observe the spin flipping transport in an H-shaped device, demonstrating evidently the spin non-conservation of the boundary states.
Identifiants
pubmed: 32591512
doi: 10.1038/s41467-020-17039-1
pii: 10.1038/s41467-020-17039-1
pmc: PMC7320166
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
3227Subventions
Organisme : National Natural Science Foundation of China (National Science Foundation of China)
ID : 11804101
Organisme : National Natural Science Foundation of China (National Science Foundation of China)
ID : 11890701
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