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Effects of spin imbalance on the electric-field driven quantum dissipationless spin current in $p$-doped Semiconductors

Liangbin Hu·Ju Gao·Shun-Qing Shen
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Abstract

It was proposed recently by Murakami et al. [Science \textbf{301}, 1348(2003)] that in a large class of $p$-doped semiconductors, an applied electric field can drive a quantum dissipationless spin current in the direction perpendicular to the electric field. In this paper we investigate the effects of spin imbalance on this intrinsic $spin$ Hall effect. We show that in a real sample with boundaries, due to the presence of spin imbalance near the edges of the sample, the spin Hall conductivity is not a constant but a sensitively $position$-$dependent$ quantity, and due to this fact, in order to take the effects of spin imbalance properly into account, a microscopic calculation of both the quantum dissipationless spin Hall current and the spin accumulation on an equal footing is thus required. Based on such a microscopic calculation, a detailed discussion of the effects of spin imbalance on the intrinsic spin Hall effect in thin slabs of $p$-doped semiconductors are presented.

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Liangbin Hu, Ju Gao, Shun-Qing Shen. 2004-10-18. Effects of spin imbalance on the electric-field driven quantum dissipationless spin current in $p$-doped Semiconductors. https://doi.org/10.1103/physrevb.70.235323

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