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Space-time dispersion of graphene conductivity

L. A. Falkovsky·A. A. Varlamov
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Abstract

We present an analytic calculation of the conductivity of pure graphene as a function of frequency $ω$, wave-vector $k$, and temperature for the range where the energies related to all these parameters are small in comparison with the band parameter $γ=3$ eV. The simple asymptotic expressions are given in various limiting cases. For instance, the conductivity for $kv_{0}\ll T\ll ω$ is equal to $σ(ω, k)=e^{2}/4\hbar $ and independent of the band structure parameters $γ$ and $v_{0}$. Our results are also used to explain the known dependence of the graphite conductivity on temperature and pressure.

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L. A. Falkovsky, A. A. Varlamov. 2006-06-30. Space-time dispersion of graphene conductivity. https://doi.org/10.1140/epjb%2Fe2007-00142-3

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