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.
Custodial glide symmetry of quantum spin Hall edge modes in monolayer WTe2 / Ok, S.; Muechler, L.; Di Sante, D.; Sangiovanni, G.; Thomale, R.; Neupert, T.. - In: PHYSICAL REVIEW. B, RAPID COMMUNICATIONS. - ISSN 1089-4896. - ELETTRONICO. - 99:12(2019), pp. 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.