Structural stability and topological surface states of the SnTe (111) surface

We perform first-principles calculations to study the stability and electronic structure of the (111) surface of SnTe, a representative topological crystalline insulator (TCI). We find three stable surface phases, which support two qualitatively different types of topological surface states: type I...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B, Condensed matter and materials physics Condensed matter and materials physics, 2014-03, Vol.89 (12), Article 125308
Main Authors: Wang, Jianfeng, Liu, Junwei, Xu, Yong, Wu, Jian, Gu, Bing-Lin, Duan, Wenhui
Format: Article
Language:English
Subjects:
Condensed matter
Crystal structure
Insulators
Mathematical analysis
Phases
Reconstruction
Structural stability
Tin
Topology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We perform first-principles calculations to study the stability and electronic structure of the (111) surface of SnTe, a representative topological crystalline insulator (TCI). We find three stable surface phases, which support two qualitatively different types of topological surface states: type I with four Dirac points at [Gamma] and three M points and type II with two Dirac points nearby but not at [Gamma]. Their appearance can be controlled by varying growth conditions. Under an Sn-poor condition, the Te-terminated surface without reconstruction is stable, resulting in the type-I surface states. While under an Sn-rich condition, the (2 x 1)-reconstructed Sn-terminated surface becomes more stable. The reconstruction folds the surface Brillouin zone and effectively induces interactions between the Dirac points at the [Gamma] and M points. Surface states thus change from type I to type II accompanied by a Lifshitz transition. Under intermediate growth conditions, the ([radic]3 x [radic]3)-reconstructed Sn-terminated surface gets stabilized, which recovers the type-I surface states. Our work suggests a promising alternative way to control the topological surface states of TCIs besides selecting different surface orientations.
ISSN:1098-0121
1550-235X
DOI:10.1103/PhysRevB.89.125308