Linear magnetoresistance in HgTe quantum wells

Abstract

We report magnetotransport measurements in a HgTe quantum well with an inverted band structure, which is expected to be a two-dimensional (2D) topological insulator. A small magnetic field perpendicular the 2D layer breaks the time reversal symmetry and thereby, suppresses the edge state transport. A linear magnetoresistance is observed in low magnetic fields, when the chemical potential moves through the the bulk gap. That magnetoresistance is well described by numerical calculations of the edge states magnetotransport in the presence of nonmagnetic disorder. With magnetic field increasing the resistance, measured both in the local and nonlocal configurations first sharply decreases and then increases again in disagreement with the existing theories.