Topological band inversion in HgTe(001): Surface and bulk signatures from photoemission

Abstract

HgTe is a prime example of a topological material that exhibits a range of topological phases based on its dimensionality and lattice strain. The key to its topological properties lies in the band inversion between the Hg 6$s$ and Te 5$p$ valence levels, leading to the emergence of surface states. In this study, the authors present an in-depth examination of the electronic structure of strained HgTe films using angle-resolved photoelectron spectroscopy and density functional theory. The results offer a direct visualization of the topological band inversion and surface states present in HgTe.