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arXiv · 1304.0654

Resonant valley filtering of massive Dirac electrons

D. Moldovan·M. Ramezani Masir·L. Covaci·F. M. Peeters
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Abstract

Electrons in graphene, in addition to their spin, have two pseudospin degrees of freedom: sublattice and valley pseudospin. Valleytronics uses the valley degree of freedom as a carrier of information similar to the way spintronics uses electron spin. We show how a double barrier structure consisting of electric and vector potentials can be used to filter massive Dirac electrons based on their valley index. We study the resonant transmission through a finite number of barriers and we obtain the energy spectrum of a superlattice consisting of electric and vector potentials. When a mass term is included the energy bands and energy gaps at the K and K' points are different and they can be tuned by changing the potential.

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D. Moldovan, M. Ramezani Masir, L. Covaci, F. M. Peeters. 2013-04-02. Resonant valley filtering of massive Dirac electrons. https://doi.org/10.1103/physrevb.86.115431

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