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Orbital ac spin-Hall effect in the hopping regime

O. Entin-Wohlman·A. Aharony·Y. M. Galperin·V. I. Kozub·V. Vinokur
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Abstract

The Rashba and Dresselhaus spin-orbit interactions are both shown to yield the low temperature spin-Hall effect for strongly localized electrons coupled to phonons. A frequency-dependent electric field ${\bf E}(ω)$ generates a spin-polarization current, normal to ${\bf E}$, due to interference of hopping paths. At zero temperature the corresponding spin-Hall conductivity is real and is proportional to $ω^{2}$. At non-zero temperatures the coupling to the phonons yields an imaginary term proportional to $ω$. The interference also yields persistent spin currents at thermal equilibrium, at ${\bf E}=0$. The contributions from the Dresselhaus and Rashba interactions to the interference oppose each other.

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O. Entin-Wohlman, A. Aharony, Y. M. Galperin, V. I. Kozub, V. Vinokur. 2005-02-19. Orbital ac spin-Hall effect in the hopping regime. https://doi.org/10.1103/physrevlett.95.086603

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