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arXiv · 1610.04053

Relaxation of charge in monolayer graphene: fast non-linear diffusion vs Coulomb effects

Eugene B. Kolomeisky·Joseph P. Straley
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Abstract

Pristine monolayer graphene exhibits very poor screening because the density of states vanishes at the Dirac point. As a result, charge relaxation is controlled by the effects of zero-point motion (rather than by the Coulomb interaction) over a wide range of parameters. Combined with the fact that graphene possesses finite intrinsic conductivity, this leads to a regime of relaxation described by a non-linear diffusion equation with a diffusion coefficient that diverges at zero charge density. Some consequences of this fast diffusion are self-similar superdiffusive regimes of relaxation, the development of a charge depleted region at the interface between electron- and hole-rich regions, and finite extinction times for periodic charge profiles.

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Eugene B. Kolomeisky, Joseph P. Straley. 2016-10-13. Relaxation of charge in monolayer graphene: fast non-linear diffusion vs Coulomb effects. https://doi.org/10.1103/physrevb.95.045415

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