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arXiv · 0907.4078

Spin Hall effect due to intersubband-induced spin-orbit interaction in symmetric quantum wells

Minchul Lee·Marco O. Hachiya·E. Bernardes·J. Carlos Egues·Daniel Loss
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Abstract

We investigate the intrinsic spin Hall effect in two-dimensional electron gases in quantum wells with two subbands, where a new intersubband-induced spin-orbit coupling is operative. The bulk spin Hall conductivity $σ^z_{xy}$ is calculated in the ballistic limit within the standard Kubo formalism in the presence of a magnetic field $B$ and is found to remain finite in the B=0 limit, as long as only the lowest subband is occupied. Our calculated $σ^z_{xy}$ exhibits a nonmonotonic behavior and can change its sign as the Fermi energy (the carrier areal density $n_{2D}$) is varied between the subband edges. We determine the magnitude of $σ^z_{xy}$ for realistic InSb quantum wells by performing a self-consistent calculation of the intersubband-induced spin-orbit coupling.

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Minchul Lee, Marco O. Hachiya, E. Bernardes, J. Carlos Egues, Daniel Loss. 2009-10-15. Spin Hall effect due to intersubband-induced spin-orbit interaction in symmetric quantum wells. https://doi.org/10.1103/physrevb.80.155314

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