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arXiv · 1708.03712

Spin relaxation in disordered graphene: Interplay between puddles and defect-induced magnetism

Vladimir G. Miranda·Eduardo R. Mucciolo·Caio H. Lewenkopf
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Abstract

We study the spin relaxation in graphene due to magnetic moments induced by defects. We propose and employ in our studies a microscopic model that describes magnetic impurity scattering processes mediated by charge puddles. This model incorporates the spin texture related to the defect-induced state. We calibrate our model parameters using experimentally-inferred values. The results we obtain for the spin relaxation times are in very good agreement with experimental findings. Our study leads to a comprehensive explanation for the short spin relaxation times reported in the experimental literature. We also propose a new interpretation for the puzzling experimental observation of enhanced spin relaxation times in hydrogenated graphene samples in terms of a combined effect due to disorder configurations that lead to an increased coupling to the magnetic moments and the tunability of the defect-induced $\pi$-like magnetism in graphene.

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Vladimir G. Miranda, Eduardo R. Mucciolo, Caio H. Lewenkopf. 2017-08-11. Spin relaxation in disordered graphene: Interplay between puddles and defect-induced magnetism. https://doi.org/10.1016/j.jpcs.2017.10.022

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