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arXiv · 1210.1801

Anisotropy of spin relaxation in metals

Bernd Zimmermann·Phivos Mavropoulos·Swantje Heers·Nguyen H. Long·Stefan Blügel·Yuriy Mokrousov
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Abstract

The concept of anisotropy of spin relaxation in non-magnetic metals with respect to the spin direction of the injected electrons relative to the crystal orientation is introduced. The effect is related to an anisotropy of the Elliott-Yafet parameter, arising from a modulation of the decomposition of the spin-orbit Hamiltonian into spin-conserving and spin-flip terms as the spin quantization axis is varied. This anisotropy, reaching gigantic values for uniaxial transition-metals (e.g. 830% for hcp Hf) as density-functional calculations show, is related to extended "spin-flip hot areas" on the Fermi surface created by the proximity of extended sheets of the surface, or "spin-flip hot loops" at the Brillouin zone boundary, and has no theoretical upper limit. Possible ways of measuring the effect as well as consequences in application are briefly outlined.

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Bernd Zimmermann, Phivos Mavropoulos, Swantje Heers, Nguyen H. Long, Stefan Blügel, Yuriy Mokrousov. 2012-10-05. Anisotropy of spin relaxation in metals. https://doi.org/10.1103/physrevlett.109.236603

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