Effective g-factors of carriers in inverted InAs/GaSb bilayers

TL;DR

This study investigates the effective g-factors of electrons and holes in inverted InAs/GaSb bilayers using tilt-field transport experiments, revealing distinct behaviors and values for each carrier type.

Contribution

It provides systematic measurements of Landau level spectra and g-factors for carriers in InAs/GaSb bilayers, highlighting differences between electrons and holes.

Findings

Electron g-factor approximately 11.5, constant across densities.

Hole g-factor less than 3, with minimal Zeeman splitting.

Landau level crossing and anti-crossing behaviors observed.

Abstract

We perform tilt-field transport experiment on inverted InAs/GaSb which hosts quantum spin Hall insulator. By means of coincidence method, Landau level (LL) spectra of electron and hole carriers are systematically studied at different carrier densities tuned by gate voltages. When Fermi level stays in the conduction band, we observe LL crossing and anti-crossing behaviors at odd and even filling factors respectively, with a corresponding g-factor of 11.5. It remains nearly constant for varying filling factors and electron densities. On the contrary, for GaSb holes only a small Zeeman splitting is observed even at large tilt angles, indicating a g-factor of less than 3.