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arXiv · 1609.09782

First-principles Study of Rashba Effect in Ultra-thin Bismuth Surface Alloys

Naoya Yamaguchi·Hiroki Kotaka·Fumiyuki Ishii
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Abstract

We performed density functional calculations for ultra-thin bismuth surface alloys: surface alloys of bismuth and face-centered cubic metals Bi/$M$(111)-$(\sqrt{3}\times\sqrt{3})R30\deg$ ($M$=Cu, Ag, Au, Ni, Co, and Fe). Our calculated Rashba parameters for the Bi/Ag are consistent with the previous experimental and theoretical results. We predicted a trend in the Rashba coefficients $\alpha_R$ of bands around the Fermi energy for noble metals as follows: Bi/Ag > Bi/Cu > Bi/Au. As for the transition metals, there is a trend in $\alpha_R$: Bi/Ni > Bi/Co > Bi/Fe. Our finding may lead to design efficient spin-charge conversion materials.

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Naoya Yamaguchi, Hiroki Kotaka, Fumiyuki Ishii. 2016-09-30. First-principles Study of Rashba Effect in Ultra-thin Bismuth Surface Alloys. https://doi.org/10.1016/j.jcrysgro.2016.09.075

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