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arXiv · 0907.1631

Electron transport and Goos-Hanchen shift in graphene with electric and magnetic barriers: optical analogy and band structure

Manish Sharma·Sankalpa Ghosh
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Abstract

Transport of massless Dirac fermions in graphene monolayers is analyzed in the presence of a combination of singular magnetic barriers and applied electrostatic potential. Extending a recently proposed (J Phys. Cond. Matt. Vol 21, 292204 (2009)) analogy between the transmission of light through a medium with modulated refractive index and electron transmission in graphene through singular magnetic barriers to the present case, we find the addition of a scalar potential profoundly changes the transmission. We calculate the quantum version of the Goos-Hänchen shift that the electron wave suffers upon being totally reflected by such barriers. The combined electric and magnetic barriers substantially modify the band structure near the Dirac point. This affects transport near the Dirac point significantly and has important consequences for graphene-based electronics.

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Manish Sharma, Sankalpa Ghosh. 2010-12-31. Electron transport and Goos-Hanchen shift in graphene with electric and magnetic barriers: optical analogy and band structure. https://doi.org/10.1088/0953-8984%2F23%2F5%2F055501

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