Electrical resistance of individual defects at a topological insulator surface
Abstract
Three-dimensional topological insulators host surface states with linear dispersion, which manifest as a Dirac cone. Nanoscale transport measurements provide direct access to the transport properties of the Dirac cone in real space and allow the detailed investigation of charge carrier scattering. Here, we use scanning tunnelling potentiometry to analyse the resistance of different kinds of defects at the surface of a (Bi0.53Sb0.47)2Te3 topological insulator thin film. The largest localized voltage drop we find to be located at domain boundaries in the topological insulator film, with a resistivity about four times higher than that of a step edge. Furthermore, we resolve resistivity dipoles located around nanoscale voids in the sample surface. The influence of such defects on the resistance of the topological surface state is analysed by means of a resistor network model. The effect resulting from the voids is found to be small compared to the other defects.
Keywords
Cite
@article{arxiv.1704.06580,
title = {Electrical resistance of individual defects at a topological insulator surface},
author = {Felix Lüpke and Markus Eschbach and Tristan Heider and Martin Lanius and Peter Schüffelgen and Daniel Rosenbach and Nils von den Driesch and Vasily Cherepanov and Gregor Mussler and Lukasz Plucinski and Detlev Grützmacher and Claus M. Schneider and Bert Voigtländer},
journal= {arXiv preprint arXiv:1704.06580},
year = {2017}
}