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arXiv · 0808.1459

Giant Extrinsic Spin Hall Effect due to Rare-Earth Impurities

T. Tanaka·H. Kontani
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Abstract

We investigate the extrinsic spin Hall effect in the electron gas model due to magnetic impurities, by focusing on Ce- and Yb-impurities. In the dilute limit, the skew scattering term dominates the side jump term. For Ce-impurities, the spin Hall angle $α_{\rm SH}$ due to skew scattering is given by $-8π\sinδ_2/7$, where $δ_2 (\ll 1)$ is the phase shift for$d (l=2)$ partial wave. Since $α_{\rm SH}$ reaches $O(10^{-1})$ if $δ_2 \simge 0.03$, the spin Hall effect is anticipated to be considerable in metals with rare-earth impurities. The giant extrinsic SHE originates from the large orbital angular momentum, which is also significant for the intrinsic SHE.

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T. Tanaka, H. Kontani. 2008-12-04. Giant Extrinsic Spin Hall Effect due to Rare-Earth Impurities. https://doi.org/10.1088/1367-2630%2F11%2F1%2F013023

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