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arXiv · 1507.03841

Influence of impurity spin dynamics on quantum transport in epitaxial graphene

Samuel Lara-Avila·Sergey Kubatkin·Oleksiy Kashuba·Joshua A. Folk·Silvia Lüscher·Rositza Yakimova·T. J. B. M. Janssen·Alexander Tzalenchuk·Vladimir Fal'ko
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Abstract

Experimental evidence from both spin-valve and quantum transport measurements points towards unexpectedly fast spin relaxation in graphene. We report magnetotransport studies of epitaxial graphene on SiC in a vector magnetic field showing that spin relaxation, detected using weak-localisation analysis, is suppressed by an in-plane magnetic field, $B_{\parallel}$, and thereby proving that it is caused at least in part by spinful scatterers. A non-monotonic dependence of effective decoherence rate on $B_{\parallel}$ reveals the intricate role of scatterers' spin dynamics in forming the interference correction to conductivity, an effect that has gone unnoticed in earlier weak localisation studies

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Samuel Lara-Avila, Sergey Kubatkin, Oleksiy Kashuba, Joshua A. Folk, Silvia Lüscher, Rositza Yakimova, T. J. B. M. Janssen, Alexander Tzalenchuk, Vladimir Fal'ko. 2015-07-14. Influence of impurity spin dynamics on quantum transport in epitaxial graphene. https://doi.org/10.1103/physrevlett.115.106602

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