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arXiv · 1412.3329

Novel Type of Superlattices Based on Gapless Graphene with the Alternating Fermi Velocity

P. V. Ratnikov·A. P. Silin
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Abstract

We study a novel type of graphene-based superlattices formed owing to a periodic modulation of the Fermi surface. Such a modulation is possible for graphene deposited on a striped substrate made of materials with substantially different values of the dc permittivity. Similar superlattices appear also in graphene sheets applied over substrates with a periodic array of parallel grooves. We suggest a model describing such superlattices. Using the transfer-matrix technique, we determine the dispersion relation and calculate the energy spectrum of these superlattices. We also analyze at a qualitative level the current--voltage characteristics of the system under study.

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P. V. Ratnikov, A. P. Silin. 2014-12-10. Novel Type of Superlattices Based on Gapless Graphene with the Alternating Fermi Velocity. https://doi.org/10.1134/s0021364014170123

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