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arXiv · 1003.2669

Tunneling Spin Injection into Single Layer Graphene

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

We achieve tunneling spin injection from Co into single layer graphene (SLG) using TiO2 seeded MgO barriers. A non-local magnetoresistance ({\Delta}RNL) of 130 {\Omega} is observed at room temperature, which is the largest value observed in any material. Investigating {\Delta}RNL vs. SLG conductivity from the transparent to the tunneling contact regimes demonstrates the contrasting behaviors predicted by the drift-diffusion theory of spin transport. Furthermore, tunnel barriers reduce the contact-induced spin relaxation and are therefore important for future investigations of spin relaxation in graphene.

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Wei Han, K. Pi, K. M. McCreary, Yan Li, Jared J. I. Wong, A. G. Swartz, R. K. Kawakami. 2010-03-13. Tunneling Spin Injection into Single Layer Graphene. https://doi.org/10.1103/physrevlett.105.167202

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