Time-reversal-breaking induced quantum spin Hall effect.
Sci Rep
; 7: 43049, 2017 02 21.
Article
em En
| MEDLINE
| ID: mdl-28220858
ABSTRACT
We show that quantum spin Hall (QSH) effect does not occur in a square lattice model due to cancellation of the intrinsic spin-orbit coupling coming from different hopping paths. However, we show that QSH effect can be induced by the presence of staggered magnetic fluxes alternating directions square by square. When the resulting Peierls phase takes a special value , the system has a composite symmetry ΘΡ- with Θ the time-reversal operator and Ρ- transforming the Peierls phase from γ to γ - , which protects the gapless edge states. Once the phase deviates from , the edge states open a gap, as the composite symmetry is broken. We further investigate the effect of a Zeeman field on the QSH state, and find that the edge states remain gapless for . This indicates that the QSH effect is immune to the magnetic perturbation.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Sci Rep
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
China