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arXiv · 0812.1921

Spin-Orbit-Mediated Spin Relaxation in Graphene

D. Huertas-Hernando·F. Guinea·A. Brataas
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Abstract

We investigate how spins relax in intrinsic graphene. The spin-orbit coupling arises from the band structure and is enhanced by ripples. The orbital motion is influenced by scattering centers and ripple-induced gauge fields. Spin relaxation due to Elliot-Yafet and Dyakonov-Perel mechanisms and gauge fields in combination with spin-orbit coupling are discussed. In intrinsic graphene, the Dyakonov-Perel mechanism and spin flip due to gauge fields dominate and the spin-flip relaxation time is inversely proportional to the elastic scattering time. The spin relaxation anisotropy depends on an intricate competition between these mechanisms. Experimental consequences are discussed.

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D. Huertas-Hernando, F. Guinea, A. Brataas. 2008-12-10. Spin-Orbit-Mediated Spin Relaxation in Graphene. https://doi.org/10.1103/physrevlett.103.146801

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