Engineered Near-Perfect Back-Scattering on Surface of Topological Insulator with Non-Magnetic Impurities

TL;DR

This paper demonstrates how to induce near-perfect back-scattering and local gap-like states on the surface of topological insulators using only non-magnetic impurities, through engineered impurity structures.

Contribution

It introduces a method to enhance skew scattering and create local energy gaps on topological insulator surfaces with non-magnetic impurities, a novel approach in the field.

Findings

Enhanced skew scattering as a finite size effect.

Emergence of local gap-like density of states.

Extended energy gaps in engineered impurity structures.

Abstract

We show how to engineer enhanced skew scattering and gap-like opening in the surface state of three-dimensional topological insulators using only non-magnetic impurities. Enhanced skew scattering off non-magnetic impurities is obtained as a finite size effect of the scattering potential. Intimately related to the generated skew-scattering is the emergence of a gap-like density of electron states locally around the impurities and surrounded by sharp resonances, with an extended energy gap appearing in engineered impurity structures.