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arXiv · 1506.02127

Spin filter and spin valve in ferromagnetic graphene

Yu Song·Gang Dai
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Abstract

We propose and demonstrate that a EuO-induced and top-gated graphene ferromagnetic junction can be simultaneously operated as a spin filter as well as a spin valve. We attribute such a remarkable result to a coexistence of a half-metal band and a common energy gap for opposite spins in ferromagnetic graphene. We show that, both the spin filter and the spin valve can be effectively controlled by a back gate voltage, and they survive for practical metal contacts and finite temperature. Specifically, larger single spin currents and on-state currents can be reached with contacts with work functions similar to graphene, and the spin filter can operate at higher temperature than the spin valve.

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Yu Song, Gang Dai. 2015-06-06. Spin filter and spin valve in ferromagnetic graphene. https://doi.org/10.1063/1.4921668

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