Anisotropic Zeeman splitting in ballistic one-dimensional hole systems

TL;DR

This study investigates how an in-plane magnetic field affects spin splitting in a ballistic one-dimensional hole system, revealing extreme anisotropy in the Zeeman effect due to confinement and strong spin-orbit coupling.

Contribution

It demonstrates the anisotropic Zeeman splitting in 1D hole systems and links it to confinement effects and spin-orbit interactions, providing new insights into spin behavior in low-dimensional systems.

Findings

Zeeman splitting occurs only when magnetic field is parallel to the channel.

No Zeeman splitting detected for perpendicular magnetic field.

Anisotropy of the effective g-factor g* is directly observed.

Abstract

We have studied the effect of an in-plane magnetic field B on a one-dimensional hole system in the ballistic regime created by surface gate confinement. We observed clearly the lifting of the spin degeneracy due to the Zeeman effect on the one dimensional subbands for B applied parallel to the channel. In contrast, no Zeeman splitting is detected for B applied perpendicular to the channel, revealing an extreme anisotropy of the effective Lande g-factor g*. We demonstrate that this anisotropy is a direct consequence of the one-dimensional confinement on a system with strong spin-orbit coupling.