Imaging current distribution in a topological insulator Bi₂Se₃ in the presence of competing surface and bulk contributions to conductivity.

ABSTRACT: Two-dimensional (2D) topological surface states in a three-dimensional topological insulator (TI) should produce uniform 2D surface current distribution. However, our transport current imaging studies on Bi₂Se₃ thin film reveal non-uniform current sheet flow at 15 K with strong edge current flow. This is consistent with other imaging studies on thin films of Bi₂Se₃. In contrast to strong edge current flow in thin films, in single crystal of Bi₂Se₃ at 15 K our current imaging studies show the presence of 3.6 nm thick uniform 2D sheet current flow. Above 70 K, this uniform 2D sheet current sheet begins to disintegrate into a spatially non-uniform flow. The flow becomes patchy with regions having high and low current density. T

SUBMITTER: Jash A 

PROVIDER: S-EPMC8018954 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature