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arXiv · 1402.3867

Valley polarization in graphene-silicene-graphene heterojunction

Man Shen·Yan-Yang Zhang·Xing-Tao An·Jian-Jun Liu·Shu-Shen Li
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Abstract

Considering the difference of energy bands in graphene and silicene, we put forward a new model of the graphene-silicene-graphene (GSG) heterojunction. In the GSG, we study the valley polarization properties in a zigzag nanoribbon in the presence of an external electric field. We find the energy range associated with the bulk gap of silicene has a valley polarization more than 95%. Under the protection of the topological edge states of the silicene, the valley polarization remains even the small non-magnetic disorder is introduced. These results have certain practical significance in applications for future valley valve.

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Man Shen, Yan-Yang Zhang, Xing-Tao An, Jian-Jun Liu, Shu-Shen Li. 2014-02-17. Valley polarization in graphene-silicene-graphene heterojunction. https://doi.org/10.1063/1.4883193

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