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arXiv · 1305.4666

Intrinsic lifetime of Dirac plasmons in graphene

Alessandro Principi·Giovanni Vignale·Matteo Carrega·Marco Polini
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Abstract

Dirac plasmons in a doped graphene sheet have recently been shown to enable confinement of light to ultrasmall volumes. In this work we calculate the intrinsic lifetime of a Dirac plasmon in a doped graphene sheet by analyzing the role of electron-electron interactions beyond the random phase approximation. The damping mechanism at work is intrinsic since it operates also in disorder-free samples and in the absence of lattice vibrations. We demonstrate that graphene's sublattice-pseudospin degree of freedom suppresses intrinsic plasmon losses with respect to those that occur in ordinary two-dimensional electron liquids. We relate our findings to a microscopic calculation of the homogeneous dynamical conductivity at energies below the single-particle absorption threshold.

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Alessandro Principi, Giovanni Vignale, Matteo Carrega, Marco Polini. 2013-05-20. Intrinsic lifetime of Dirac plasmons in graphene. https://doi.org/10.1103/physrevb.88.195405

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