Ab initio calculation of intrinsic spin Hall effect in semiconductors

TL;DR

This paper uses relativistic band theory to calculate the intrinsic spin Hall effect in semiconductors like Ge, GaAs, and AlAs, showing large spin Hall conductivities and potential for manipulation via strain.

Contribution

It demonstrates the significant intrinsic spin Hall effect in semiconductors beyond traditional models and explores strain effects on spin Hall conductivity.

Findings

Large spin Hall conductivity (~100 (ħ/e)(Ωcm)^{-1}) in Ge, GaAs, and AlAs.

Orbital Hall conductivity is much smaller, indicating no cancellation.

Strain can strongly manipulate the spin Hall effect.

Abstract

Relativistic band theoretical calculations reveal that intrinsic spin Hall conductivity in hole-doped archetypical semiconductors Ge, GaAs and AlAs is large $[\sim 100 (\hbar/e)(\Omega cm)^{-1}]$, showing the possibility of spin Hall effect beyond the four band Luttinger Hamiltonian. The calculated orbital-angular-momentum (orbital) Hall conductivity is one order of magnitude smaller, indicating no cancellation between the spin and orbital Hall effects in bulk semiconductors. Furthermore, it is found that the spin Hall effect can be strongly manipulated by strains, and that the $ac$ spin Hall conductivity in the semiconductors is large in pure as well as doped semiconductors.