Low temperature Hall effect in bismuth chalcogenides thin films

TL;DR

This study investigates the low-temperature Hall effect in bismuth chalcogenide thin films, revealing that resistivity upturns are linked to electron-electron interactions, despite weak antilocalization effects.

Contribution

It provides experimental evidence connecting low-temperature resistivity increase to diffusive electron-electron interactions in topological insulator thin films.

Findings

Resistivity increases as temperature decreases.

Hall coefficient grows at low temperatures.

Data supports electron-electron interaction correction mechanism.

Abstract

Bismuth chalcogenides are the most studied 3D topological insulators. As a rule, at low temperatures thin films of these materials demonstrate positive magnetoresistance due to weak antilocalization. Weak antilocalization should lead to resistivity decrease at low temperatures; in experiments, however, resistivity grows as temperature decreases. From transport measurements for several thin films (with various carrier density, thickness, and carrier mobility), and by using purely phenomenological approach, with no microscopic theory, we show that the low temperature growth of the resistivity is accompanied by growth of the Hall coefficient, in agreement with diffusive electron-electron interaction correction mechanism. Our data reasonably explain the low-temperature resistivity upturn.