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arXiv · 1308.4248

Hole Spin Helix: Anomalous Spin Diffusion in Anisotropic Strained Hole Quantum Wells

Vincent E. Sacksteder IV·B. Andrei Bernevig
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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.

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Vincent E. Sacksteder IV, B. Andrei Bernevig. 2014-02-20. Hole Spin Helix: Anomalous Spin Diffusion in Anisotropic Strained Hole Quantum Wells. https://doi.org/10.1103/physrevb.89.161307

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