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Quantum-limited shot noise in graphene

J. Tworzydlo·B. Trauzettel·M. Titov·A. Rycerz·C. W. J. Beenakker
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Abstract

We calculate the mode-dependent transmission probability of massless Dirac fermions through an ideal strip of graphene (length L, width W, no impurities or defects), to obtain the conductance and shot noise as a function of Fermi energy. We find that the minimum conductivity of order e^2/h at the Dirac point (when the electron and hole excitations are degenerate) is associated with a maximum of the Fano factor (the ratio of noise power and mean current). For short and wide graphene strips the Fano factor at the Dirac point equals 1/3, three times smaller than for a Poisson process. This is the same value as for a disordered metal, which is remarkable since the classical dynamics of the Dirac fermions is ballistic.

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J. Tworzydlo, B. Trauzettel, M. Titov, A. Rycerz, C. W. J. Beenakker. 2006-04-10. Quantum-limited shot noise in graphene. https://doi.org/10.1103/physrevlett.96.246802

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