Gigantic negative magnetoresistance in the bulk of a disordered topological insulator

Abstract

Large negative magnetoresistance is usually related to magnetism and the exceptions are rare. Here, Breuniget al. report a large negative magnetoresistance in a topological insulator, TlBi0.15Sb0.85Te2, which is likely due to the Zeeman effect on a barely percolating current path formed in the disordered bulk.