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arXiv · 1406.2439

Nanosecond spin lifetimes in single- and few-layer graphene-hBN heterostructures at room temperature

Marc Drögeler·Frank Volmer·Maik Wolter·Bernat Terrés·Kenji Watanabe·Takashi Taniguchi·Gernot Güntherodt·Christoph Stampfer·Bernd Beschoten
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Abstract

We present a new fabrication method of graphene spin-valve devices which yields enhanced spin and charge transport properties by improving both the electrode-to-graphene and graphene-to-substrate interface. First, we prepare Co/MgO spin injection electrodes onto Si$^{++}$/SiO$_2$. Thereafter, we mechanically transfer a graphene-hBN heterostructure onto the prepatterned electrodes. We show that room temperature spin transport in single-, bi- and trilayer graphene devices exhibit nanosecond spin lifetimes with spin diffusion lengths reaching 10$μ$m combined with carrier mobilities exceeding 20,000 cm$^2$/Vs.

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Marc Drögeler, Frank Volmer, Maik Wolter, Bernat Terrés, Kenji Watanabe, Takashi Taniguchi, Gernot Güntherodt, Christoph Stampfer, Bernd Beschoten. 2014-06-10. Nanosecond spin lifetimes in single- and few-layer graphene-hBN heterostructures at room temperature. https://doi.org/10.1021/nl501278c

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