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arXiv · 1311.3968

Tunable zero-energy transmission resonances in shifted graphene bilayer

A. Daboussi·L. Mandhour·J. N. Fuchs·S. Jaziri
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Abstract

A graphene bilayer is known to perfectly reflect normally incident electrons due to their chirality. This is similar to Klein tunneling, which, in a monolayer, is instead responsible for perfect transmission at normal incidence. Stacking defaults turn each parabolic band crossing of a bilayer into pairs of Dirac cones. Here we show that, surprisingly, a stacking default (or shift) in a bilayer can result in perfect {\it transmission} at normal incidence as a result of Fabry-P\'erot type resonances {\it at zero-energy}. These constructive interferences only happen for a specific orientation of the Dirac cones with respect to the incident electron and for quantized values of their separation in reciprocal space. Our results provide a way to control transmission resonances in undoped graphene bilayer structure by adjusting the layer stacking.

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A. Daboussi, L. Mandhour, J. N. Fuchs, S. Jaziri. 2013-11-15. Tunable zero-energy transmission resonances in shifted graphene bilayer. https://doi.org/10.1103/physrevb.89.085426

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