Nguyen H. Long, Phivos Mavropoulos, Swantje Heers, Bernd Zimmermann, Yuriy Mokrousov, Stefan Blügel
Spin-flip hot spots, i.e., special k-points on the Fermi surface showing a high spin-mixing parameter, are found on the surface Brillouin zone boundary of ultrathin films of monovalent (noble and alkali) metals, in contrast to the long-known fact that they do not occur in the bulk of these metals. Density-functional calculations within the Korringa-Kohn-Rostoker Green function method in Cu, Ag, and Au 10-layer (001)-films show that the hot spots can have a substantial contribution, e.g. 49% in Au(001), to the integrated spin-mixing parameter, that could lead to a significant enhancement of the spin-relaxation rate or spin-Hall angle. Owing to the appearance of spin-flip hot spots, a gigantic anisotropy of the Elliott-Yafet parameter [52% for Au(001)] is also found in these systems. The findings are important for spintronics applications in which the dimensionality of spin probes is reduced.
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http://arxiv.org/abs/1302.4671
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