Isotropic and Anisotropic g-factor Corrections in GaAs Quantum Dots

TL;DR

This paper experimentally investigates the isotropic and anisotropic g-factor corrections in GaAs quantum dots by measuring Zeeman splitting and analyzing the effects of spin-orbit interactions, which are crucial for spin qubit applications.

Contribution

It provides the first detailed experimental quantification of both isotropic and anisotropic g-factor corrections in GaAs quantum dots, linking them to spin-orbit interactions.

Findings

Zeeman splitting depends linearly on magnetic field strength.

Measured g-factor shows anisotropy depending on magnetic field direction.

Spin-orbit interactions cause significant corrections to the bulk g-factor.

Abstract

We experimentally determine isotropic and anisotropic g-factor corrections in lateral GaAs single-electron quantum dots. We extract the Zeeman splitting by measuring the tunnel rates into the individual spin states of an empty quantum dot for an in-plane magnetic field with various strengths and directions. We quantify the Zeeman energy and find a linear dependence on the magnetic field strength which allows us to extract the g-factor. The measured g-factor is understood in terms of spin-orbit interaction induced isotropic and anisotropic corrections to the GaAs bulk g-factor. Because this implies a dependence of the spin splitting on the magnetic field direction, these findings are of significance for spin qubits in GaAs quantum dots.