First Principles Studies on 3-Dimentional Strong Topological Insulators: Bi2Te3, Bi2Se3 and Sb2Te3

摘要

Bi2Se3, Bi2Te3 and Sb2Te3 compounds are recently predicted to be3-dimentional (3D) strong topological insulators. In this paper, based onab-initio calculations, we study in detail the topological nature and thesurface states of this family compounds. The penetration depth and thespin-resolved Fermi surfaces of the surface states will be analyzed. We willalso present an procedure, from which highly accurate effective Hamiltonian canbe constructed, based on projected atomic Wannier functions (which keep thesymmetries of the systems). Such Hamiltonian can be used to study thesemi-infinite systems or slab type supercells efficiently. Finally, we discussthe 3D topological phase transition in Sb2(Te1-xSex)3 alloy system.