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arXiv · 1003.0715

Manipulation of Spin Transport in Graphene by Surface Chemical Doping

K. Pi·Wei Han·K. M. McCreary·A. G. Swartz·Yan Li·R. K. Kawakami
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Abstract

The effects of surface chemical doping on spin transport in graphene are investigated by performing non-local measurements in ultrahigh vacuum while depositing gold adsorbates. We demonstrate manipulation of the gate-dependent non-local spin signal as a function of gold coverage. We discover that charged impurity scattering is not the dominant mechanism for spin relaxation in graphene, despite its importance for momentum scattering. Finally, unexpected enhancements of the spin lifetime illustrate the complex nature of spin relaxation in graphene.

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K. Pi, Wei Han, K. M. McCreary, A. G. Swartz, Yan Li, R. K. Kawakami. 2010-03-03. Manipulation of Spin Transport in Graphene by Surface Chemical Doping. https://doi.org/10.1103/physrevlett.104.187201

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