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arXiv · 1808.03919

Band gap engineering in AA-stacked bilayer graphene

Hasan M. Abdullah·Mohammed Al Ezzi·H. Bahlouli
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Abstract

We demonstrate that AA-stacked bilayer graphene (AA-BLG) encapsulated by dielectric materials can possess an energy gap due to the induced mass term. Using the four-band continuum model, we evaluate transmission and reflection probabilities along with the respective conductance. Considering interlayer mass-term difference opens a gap in the energy spectrum and also couples the two Dirac cones. This cone coupling induces an inter-cone transport that is asymmetric with respect to the normal incidence in the presence of asymmetric mass-term. The energy spectrum of the gapped AA-BLG exhibits electron-hole asymmetry that is reflected in the associated intra- and inter-cone channels. We also find that even though Klein tunneling exists in gated and biased AA-BLG, it is precluded by the interlayer mass-term difference and instead Febry-Pérot resonances appear.

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Hasan M. Abdullah, Mohammed Al Ezzi, H. Bahlouli. 2018-08-27. Band gap engineering in AA-stacked bilayer graphene. https://doi.org/10.1063/1.5052402

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