# Electrical control of the sign of the g-factor in a GaAs hole quantum point contact

## TL;DR

This paper demonstrates electrical control over both the magnitude and sign of the g-factor in a GaAs hole quantum point contact, using tilted magnetic fields and g-tensor properties, with implications for spintronics.

## Contribution

It introduces a method to electrically tune the sign of the g-factor in GaAs hole QPCs, combining experimental detection with theoretical explanation of the behavior.

## Key findings

- Able to switch g-factor sign electrically
- Direct detection of g-factor sign using off-diagonal g-tensor elements
- Behavior explained by momentum-dependent spin-orbit interaction

## Abstract

Zeeman splitting of 1D hole subbands is investigated in quantum point contacts (QPCs) fabricated on a (311) oriented GaAs-AlGaAs heterostructure. Transport measurements can determine the magnitude of the g-factor, but cannot usually determine the sign. Here we use a combination of tilted fields and a unique off-diagonal element in the hole g-tensor to directly detect the sign of g*. We are able to tune not only the magnitude, but also the sign of the g-factor by electrical means, which is of interest for spintronics applications. Furthermore, we show theoretically that the resulting behavior of g* can be explained by the momentum dependence of the spin-orbit interaction.