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arXiv · 0905.0424

Electron spin relaxation in graphene: the role of the substrate

C. Ertler·S. Konschuh·M. Gmitra·J. Fabian
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Abstract

Theory of the electron spin relaxation in graphene on the SiO$_2$ substrate is developed. Charged impurities and polar optical surface phonons in the substrate induce an effective random Bychkov-Rashba-like spin-orbit coupling field which leads to spin relaxation by the D'yakonov-Perel' mechanism. Analytical estimates and Monte Carlo simulations show that the corresponding spin relaxation times are between micro- to milliseconds, being only weakly temperature dependent. It is also argued that the presence of adatoms on graphene can lead to spin lifetimes shorter than nanoseconds.

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C. Ertler, S. Konschuh, M. Gmitra, J. Fabian. 2009-05-04. Electron spin relaxation in graphene: the role of the substrate. https://doi.org/10.1103/physrevb.80.041405

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