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Ballistic transmission through a graphene bilayer

I. Snyman·C. W. J. Beenakker
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Abstract

We calculate the Fermi energy dependence of the (time-averaged) current and shot noise in an impurity-free carbon bilayer (length $L\ll$ width $W$), and compare with known results for a monolayer. At the Dirac point of charge neutrality, the bilayer transmits as two independent monolayers in parallel: Both current and noise are resonant at twice the monolayer value, so that their ratio (the Fano factor) has the same 1/3 value as in a monolayer -- and the same value as in a diffusive metal. The range of Fermi energies around the Dirac point within which this pseudo-diffusive result holds is smaller, however, in a bilayer than in a monolayer (by a factor $l_{\perp}/L$, with $l_{\perp}$ the interlayer coupling length).

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I. Snyman, C. W. J. Beenakker. 2006-12-12. Ballistic transmission through a graphene bilayer. https://doi.org/10.1103/physrevb.75.045322

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