Large variations in the hole spin splitting of quantum-wire subband edges

TL;DR

This paper investigates the Zeeman splitting of subband edges in cylindrical hole wires, revealing significant variations in g-factors influenced by confinement and spin polarization, with implications for spintronic device engineering.

Contribution

It provides a detailed analysis of hole spin splitting in quantum wires, highlighting the strong dependence of g-factors on subband index and spin polarization profiles, which was not previously well understood.

Findings

g-factors fluctuate strongly with subband index

g-factors differ from higher-dimensional systems

hole-spin polarization correlates with g-factor values

Abstract

We study Zeeman splitting of zone-center subband edges in a cylindrical hole wire subject to a magnetic field parallel to its axis. The g-factor turns out to fluctuate strongly as a function of wire-subband index, assuming values that differ substantially from those found in higher-dimensional systems. We analyze the spin properties of hole-wire states using invariants of the spin-3/2 density matrix and find a strong correlation between g-factor value and the profile of hole-spin polarization density. Our results suggest possibilities for confinement engineering of hole spin splittings.