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arXiv · 1303.7014

Post-transient relaxation in graphene after an intense laser pulse

Junhua Zhang·Tianqi Li·Jigang Wang·Joerg Schmalian
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Abstract

High intensity laser pulses were recently shown to induce a population inverted transient state in graphene [T. Li et al. Phys. Rev. Lett. 108, 167401 (2012)]. Using a combination of hydrodynamic arguments and a kinetic theory we determine the post-transient state relaxation of hot, dense, population inverted electrons towards equilibrium. The cooling rate and charge-imbalance relaxation rate are determined from the Boltzmann-equation including electron-phonon scattering. We show that the relaxation of the population inversion, driven by inter-band scattering processes, is much slower than the relaxation of the electron temperature, which is determined by intra-band scattering processes. This insight may be of relevance for the application of graphene as an optical gain medium.

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Junhua Zhang, Tianqi Li, Jigang Wang, Joerg Schmalian. 2013-03-28. Post-transient relaxation in graphene after an intense laser pulse. https://doi.org/10.1140/epjst%2Fe2013-01920-2

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