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arXiv · 1407.0651

Spin-dependent THz oscillator based on hybrid graphene superlattices

E. Díaz·K. Miralles·F. Domínguez-Adame·C. Gaul
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Abstract

We theoretically study the occurrence of Bloch oscillations in biased hybrid graphene systems with spin-dependent superlattices. The spin-dependent potential is realized by a set of ferromagnetic insulator strips deposited on top of a gapped graphene nanoribbon, which induce a proximity exchange splitting of the electronic states in the graphene monolayer. We numerically solve the Dirac equation and study Bloch oscillations in the lowest conduction band of the spin-dependent superlattice. While the Bloch frequency is the same for both spins, we find the Bloch amplitude to be spin dependent. This difference results in a spin-polarized ac electric current in the THz range.

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E. Díaz, K. Miralles, F. Domínguez-Adame, C. Gaul. 2014-09-09. Spin-dependent THz oscillator based on hybrid graphene superlattices. https://doi.org/10.1063/1.4895673

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