Elastic scattering of surface states on three-dimensional topological insulators

TL;DR

This paper investigates how elastic scattering affects surface states in three-dimensional topological insulators, revealing interference patterns caused by various defects and comparing theoretical predictions with experimental observations.

Contribution

It provides a comprehensive theoretical framework for understanding elastic scattering of surface states in topological insulators, including effects of different impurities and defects.

Findings

Surface states dominate interference patterns at extremal points.

Elastic scattering patterns vary with impurity type and defect.

Theoretical results align with experimental data on BiSb, Bi2Te3, and Bi2Se3.

Abstract

Topological insulators as new type of quantum matter materials are characterized by a full insulating gap in the bulk and gapless edge/surface states which are protected by time-reversal symmetry. We propose the interference patterns caused by elastic scattering of defects or impurities are dominated by surface states at the extremal points on the constant energy contour. Within such formalism, we summarize our recent theoretical investigations on elastic scattering of topological surface states by various imperfections, including the non-magnetic impurities, magnetic impurities, step-edges, and various other defects, in comparison with recent related experiments in typical topological materials such as BiSb alloys, Bi$_2$Te$_3$ and Bi$_2$Se$_3$ crystals.