Gate-defined Two-dimensional Hole and Electron Systems in an Undoped InSb Quantum Well

TL;DR

This paper reports on the fabrication and characterization of high-quality gate-defined two-dimensional hole and electron systems in an undoped InSb quantum well, revealing tunable spin-orbit interaction, effective mass variation, and spin susceptibility properties.

Contribution

It introduces a method to create and analyze undoped InSb quantum wells with tunable spin properties, providing new insights into their spin-orbit interaction and effective mass behavior.

Findings

Tunable spin-orbit interaction observed in both hole and electron systems.

Effective mass of holes increases with carrier density.

g-factor decreases rapidly with increasing carrier density.

Abstract

Quantum transport measurements are performed in gate-defined, high-quality, two-dimensional hole and electron systems in an undoped InSb quantum well. For both polarities, the carrier systems show tunable spin-orbit interaction as extracted from weak anti-localization measurements. The effective mass of InSb holes strongly increases with carrier density as determined from the temperature dependence of Shubnikov-de Haas oscillations. Coincidence measurements in a tilted magnetic field are performed to estimate the spin susceptibility of the InSb two-dimensional hole system. The g-factor of the two-dimensional hole system decreases rapidly with increasing carrier density.