Towards layer-selective quantum spin hall channels in weak topological insulator Bi₄Br₂I₂.

ABSTRACT: Weak topological insulators, constructed by stacking quantum spin Hall insulators with weak interlayer coupling, offer promising quantum electronic applications through topologically non-trivial edge channels. However, the currently available weak topological insulators are stacks of the same quantum spin Hall layer with translational symmetry in the out-of-plane direction-leading to the absence of the channel degree of freedom for edge states. Here, we study a candidate weak topological insulator, Bi₄Br₂I₂, which is alternately stacked by three different quantum spin Hall insulators, each with tunable topologically non-trivial edge states. Our angle-resolved photoemission spectroscopy and first-principles calculations show that an energy gap opens at the c

SUBMITTER: Zhong J 

PROVIDER: S-EPMC10432521 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature