Quantized conductance and large g-factor anisotropy in InSb quantum point contacts

TL;DR

This paper reports on the observation of quantized conductance and significant g-factor anisotropy in InSb quantum point contacts, providing insights into spin properties relevant for Majorana fermion research.

Contribution

It demonstrates conductance quantization and large g-factor anisotropy in InSb quantum wells, advancing understanding of spin behavior in these systems for quantum computing.

Findings

Pronounced conductance quantization observed.

Large in-plane and out-of-plane g-factor anisotropy measured.

Electron effective mass extracted from subband depopulation.

Abstract

Due to a strong spin-orbit interaction and a large Land\'e g-factor, InSb plays an important role in research on Majorana fermions. To further explore novel properties of Majorana fermions, hybrid devices based on quantum wells are conceived as an alternative approach to nanowires. In this work, we report a pronounced conductance quantization of quantum point contact devices in InSb/InAlSb quantum wells. Using a rotating magnetic field, we observe a large in-plane (|g1|=26) and out-of-plane (|g1|=52) g-factor anisotropy. Additionally, we investigate crossings of subbands with opposite spins and extract the electron effective mass from magnetic depopulation of one-dimensional subbands.