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arXiv · 1605.07777

Valley filtering and electronic optics using polycrystalline graphene

Viet Hung Nguyen·Samuel Dechamps·Philippe Dollfus·Jean-Christophe Charlier
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Abstract

In this Letter, both the manipulation of valley-polarized currents and the optical-like behaviors of Dirac fermions are theoretically explored in polycrystalline graphene. When strain is applied, the misorientation between two graphene domains separated by a grain boundary can result in a mismatch of their electronic structures. Such a discrepancy manifests itself in a strong breaking of the inversion symmetry, leading to perfect valley polarization in a wide range of transmission directions. In addition, these graphene domains act as different media for electron waves, offering the possibility to modulate and obtain negative refraction indexes.

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Viet Hung Nguyen, Samuel Dechamps, Philippe Dollfus, Jean-Christophe Charlier. 2016-10-13. Valley filtering and electronic optics using polycrystalline graphene. https://doi.org/10.1103/physrevlett.117.247702

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