Relaxation of optically excited carriers in graphene
Date of this Version8-10-2011
Relaxation of optically excited carriers in graphene Raseong Kim, Vasili Perebeinos, and Phaedon Avouris Phys. Rev. B 84, 075449
We explore the relaxation of photoexcited 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, graphene doping, and dielectric constant.
Nanoscience and Nanotechnology