Strain effects on in-plane conductance of the topological insulator Bi2Te3

Abstract

We investigated the correlation between electrical transport and mechanical stress in a topological insulator, Bi2Te3, using conductive probe atomic force microscopy in an ultrahigh vacuum environment. After directly measuring charge transport on the cleaved Bi2Te3 surface, we found that the current density varied with applied load. Current mapping revealed a variation of the current on different terraces. The current density increased in the low-pressure regime and then decreased in the high-pressure regime. This variation of current density was explained in light of the combined effect of changes in the in-plane conductance due to spin–orbit coupling and hexagonal warping.