Resonant electron-lattice cooling in graphene

Abstract

Controlling energy flows in solids through switchable electron-lattice cooling can grant access to a range of interesting and potentially useful energy transport phenomena. Here we discuss a tunable electron-lattice cooling mechanism arising in graphene due to phonon emission mediated by resonant scattering on defects in a crystal lattice, which displays an interesting analogy to the Purcell effect in optics. In that, the electron-phonon cooling rate is enhanced due to hot carrier trapping at resonant defects. Resonant dependence of this process on carrier energy translates into gate-tunable cooling rates, exhibiting strong enhancement of cooling that occurs when the carrier energy is aligned with the electron resonance of the defect.