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arXiv · 1908.04631

Theory of the strongly nonlinear electrodynamic response of graphene: A hot electron model

S. A. Mikhailov
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Abstract

An electrodynamic response of graphene to a strong electromagnetic radiation is considered. A hot electron model (HEM) is introduced and a corresponding system of nonlinear equations is formulated. Solutions of this system are found and discussed in detail for intrinsic and doped graphene: the hot electron temperature, non-equilibrium electron and holes densities, absorption coefficient and other physical quantities are calculated as functions of the incident wave frequency $ω$ and intensity $I$, of the equilibrium chemical potential $μ_0$ and temperature $T_0$, scattering parameters, as well as of the ratio $τ_ε/τ_{\rm rec}$ of the intra-band energy relaxation time $τ_ε$ to the recombination time $τ_{\rm rec}$. The influence of the radiation intensity on the absorption coefficient $A$ at low ($\hbarω\lesssim 2|μ_0|$, $dA/dI>0$) and high ($\hbarω\gtrsim 2|μ_0|$, $dA/dI<0$) frequencies is studied. The results are shown to be in good agreement with recent experimental data.

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S. A. Mikhailov. 2019-08-13. Theory of the strongly nonlinear electrodynamic response of graphene: A hot electron model. https://doi.org/10.1103/physrevb.100.115416

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