Spin Polarization of Quasi Two-Dimensional Hole Systems

TL;DR

This paper investigates how in-plane magnetic fields influence the spin polarization of quasi two-dimensional hole systems with spin j=3/2, revealing unique behaviors like sign changes in polarization due to heavy hole-light hole splitting.

Contribution

It provides a theoretical analysis of spin polarization in 2D hole systems, highlighting differences from electron systems and predicting sign reversal of polarization at finite magnetic fields.

Findings

Spin polarization can change sign at finite magnetic field.

Heavy hole-light hole splitting significantly affects spin behavior.

Distinct from electron systems' polarization characteristics.

Abstract

In quasi two-dimensional (2D) hole systems with an effective spin j=3/2, heavy hole-light hole splitting results in a quantization of angular momentum perpendicular to the 2D plane. The spin polarization of quasi 2D hole systems due to an in-plane magnetic field B thus competes with the heavy hole-light hole splitting. As a result, the spin polarization of hole systems is very different from the spin polarization of j=1/2 electron systems. In particular, it is shown that the spin polarization of quasi 2D heavy hole systems can change its sign at a finite value of B.