A monolayer of WTe2 has been shown to display quantum spin Hall (QSH) edge modes persisting up to 100 K in transport experiments. Based on density-functional theory calculations and symmetry-based model building including the role of correlations and substrate support, we develop an effective electronic model for WTe2 that fundamentally differs from other prototypical QSH settings: we find a remarkably strong transverse localization of QSH edge modes in WTe2 related to the glide symmetry due to which the topological gap opens away from high-symmetry points in momentum space. While the indirect bulk gap is much smaller, a large direct gap of up to 1 eV in the Brillouin zone region of the dispersing edge modes determines their properties.
Ok, S., Muechler, L., Di Sante, D., Sangiovanni, G., Thomale, R., Neupert, T. (2019). Custodial glide symmetry of quantum spin Hall edge modes in monolayer WTe2. PHYSICAL REVIEW. B, RAPID COMMUNICATIONS, 99(12), 121105-121105 [10.1103/PhysRevB.99.121105].
Custodial glide symmetry of quantum spin Hall edge modes in monolayer WTe2
Di Sante, D.;
2019
Abstract
A monolayer of WTe2 has been shown to display quantum spin Hall (QSH) edge modes persisting up to 100 K in transport experiments. Based on density-functional theory calculations and symmetry-based model building including the role of correlations and substrate support, we develop an effective electronic model for WTe2 that fundamentally differs from other prototypical QSH settings: we find a remarkably strong transverse localization of QSH edge modes in WTe2 related to the glide symmetry due to which the topological gap opens away from high-symmetry points in momentum space. While the indirect bulk gap is much smaller, a large direct gap of up to 1 eV in the Brillouin zone region of the dispersing edge modes determines their properties.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
