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arXiv · 1103.5523

Relaxation of Optically Excited Carriers in Graphene

Raseong Kim·Vasili Perebeinos·Phaedon Avouris
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Abstract

We explore the relaxation of photo-excited graphene by solving a transient Boltzmann transport equation with electron-phonon (e-ph) and electron-electron (e-e) scattering. Simulations show that when the excited carriers are relaxed by e-ph scattering only, a population inversion can be achieved at energies determined by the photon energy. However, e-e scattering quickly thermalizes the carrier energy distributions washing out the negative optical conductivity peaks. The relaxation rates and carrier multiplication effects are presented as a function of photon energy and dielectric constant.

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Raseong Kim, Vasili Perebeinos, Phaedon Avouris. 2011-03-29. Relaxation of Optically Excited Carriers in Graphene. https://doi.org/10.1103/physrevb.84.075449

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