Cooling of photoexcited carriers in graphene by internal and substrate phonons
Date of this Version
7-9-2012Citation
Tony Low, Vasili Perebeinos, Raseong Kim, Marcus Freitag, and Phaedon Avouris. Phys. Rev. B 86, 045413.
Abstract
We investigate the energy relaxation of hot carriers produced by photoexcitation of graphene through coupling to both intrinsic and remote ( substrate) surface polar phonons using the Boltzmann equation approach. We find that the energy relaxation of hot photocarriers in graphene on commonly used polar substrates, under most conditions, is dominated by remote surface polar phonons. We also calculate key characteristics of the energy relaxation process, such as the transient cooling time and steady-state carrier temperatures and photocarrier densities, which determine the thermoelectric and photovoltaic photoresponse, respectively. Substrate engineering can be a promising route to efficient optoelectronic devices driven by hot carrier dynamics.
Discipline(s)
Nanoscience and Nanotechnology
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Comments
This is the published version of Tony Low, Vasili Perebeinos, Raseong Kim, Marcus Freitag, and Phaedon Avouris. Cooling of photoexcited carriers in graphene by internal and substrate phonons. First published in the Physical Review B and is available online at: https://doi.org/10.1103/PhysRevB.86.045413