Evidence of Topological Edge States in Buckled Antimonene Monolayers

Nano Lett. 2019 Sep 11;19(9):6323-6329. doi: 10.1021/acs.nanolett.9b02444. Epub 2019 Aug 23.

Abstract

Two-dimensional topological materials have attracted intense research efforts owing to their promise in applications for low-energy, high-efficiency quantum computations. Group-VA elemental thin films with strong spin-orbit coupling have been predicted to host topologically nontrivial states as excellent two-dimensional topological materials. Herein, we experimentally demonstrated for the first time that the epitaxially grown high-quality antimonene monolayer islands with buckled configurations exhibit significantly robust one-dimensional topological edge states above the Fermi level. We further demonstrated that these topologically nontrivial edge states arise from a single p-orbital manifold as a general consequence of atomic spin-orbit coupling. Thus, our findings establish monolayer antimonene as a new class of topological monolayer materials hosting the topological edge states for future low-power electronic nanodevices and quantum computations.

Keywords: Antimonene monolayer; DFT; STM; quantum spin Hall effect; topological edge state.