Substrate-limited electron dynamics in graphene

Abstract

We study the effects of polarizable substrates such as $\mathrm{Si}{\mathrm{O}}_2$ and SiC on the carrier dynamics in graphene. We find that the quasiparticle spectrum acquires a finite broadening due to the long-range interaction with the polar modes at the interface between graphene and the substrate. This mechanism results in a density dependent electrical resistivity, which exhibits a sharp increase around room temperature, where it can become the dominant limiting factor of electron transport. The effects are weaker in doped bilayer graphene due to the more conventional parabolic band dispersion. Amorphous substrates, such as polymethyl methacrylate, can induce a room temperature resistivity of comparable magnitude, although with a weaker temperature dependence.