" Energy dissipation in electric field driven graphene"*

One of the promises of graphene as a replacement in nanoelectronics relies on the unusually high drift velocities that can be achieved in graphene-based devices. The drift velocity can however be degraded through energy losses with the substrate the graphene device is coupled with, and this becomes even more pronounced in high electric fields. This makes it difficult to determine the intrinsic saturation velocity of graphene which will help to better understand its full potential for use in nanoelectronics. This work gives a full quantum treatment of the energy dissipation mechanism in graphene and sheds light on the nature of velocity saturation in graphene under high dc fields. We study the energy dissipation of a dc field driven graphene system coupled to fermionic and phononic Ohmic baths, including electron-phonon coupling. We treat this problem within the nonequilibrium DMFT framework with the Keldysh formalism. The electron and phonon transport properties are investigated and we demonstrate that in the case of large energy dissipation to the surrounding phonon baths, the drift velocity saturates to a much lower value, whereas with minimal energy losses, the drift velocity saturates to a substantially higher value.