Hole Spin Helix: Anomalous Spin Diffusion in Anisotropic Strained Hole Quantum Wells
Abstract
We obtain the spin-orbit interaction and spin-charge coupled transport equations of a two-dimensional heavy hole gas under the influence of strain and anisotropy. We show that a simple two-band Hamiltonian can be used to describe the holes. In addition to the well-known cubic hole spin-orbit interaction, anisotropy causes a Dresselhaus-like term, and strain causes a Rashba term. We discover that strain can cause a shifting symmetry of the Fermi surfaces for spin up and down holes. We predict an enhanced spin lifetime associated with a spin helix standing wave similar to the Persistent Spin Helix which exists in the two-dimensional electron gas with equal Rashba and Dresselhaus spin-orbit interactions. These results may be useful both for spin-based experimental determination of the Luttinger parameters of the valence band Hamiltonian and for creating long-lived spin excitations.
Cite
@article{arxiv.1308.4248,
title = {Hole Spin Helix: Anomalous Spin Diffusion in Anisotropic Strained Hole Quantum Wells},
author = {Vincent E. Sacksteder and B. Andrei Bernevig},
journal= {arXiv preprint arXiv:1308.4248},
year = {2015}
}