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Anomalous thermodynamics of Coulomb interacting massless Dirac fermions in two spatial dimensions

Oskar Vafek
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Abstract

It is argued that the specific heat of $N$ massless Dirac fermions in 2 spatial dimensions interacting with 1/r Coulomb interactions is suppressed logarithmically relative to its non-interacting counterpart. The (dimensionless) coefficient of the logarithm is calculated analytically in the leading order in large $N$ expansion, but to all orders in $e^2N$, a procedure which takes into account finite temperature screening. Experimental observation of this effect is expected to occur in a single layer graphene embedded in a dielectric medium. Its dependence on the dielectric constant is calculated analytically.

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Oskar Vafek. 2007-04-10. Anomalous thermodynamics of Coulomb interacting massless Dirac fermions in two spatial dimensions. https://doi.org/10.1103/physrevlett.98.216401

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