Disorder-Assisted Electron-Phonon Scattering and Cooling Pathways in Graphene

TL;DR

This paper predicts that disorder-assisted supercollisions dominate electron cooling in graphene across a wide temperature range, with the cooling rate tunable by disorder, offering new avenues for hot-carrier applications.

Contribution

It introduces disorder-assisted supercollisions as the dominant cooling mechanism in graphene and describes how disorder levels influence cooling rates.

Findings

Supercollisions dominate electron cooling in graphene.

Cooling rate varies significantly with disorder.

Characteristic T^3 temperature dependence observed.

Abstract

We predict that graphene is a unique system where disorder-assisted scattering (supercollisions) dominates electron-lattice cooling over a wide range of temperatures, up to room temperature. This is so because for momentum-conserving electron-phonon scattering the energy transfer per collision is severely constrained due to a small Fermi surface size. The characteristic $T^3$ temperature dependence and power-law cooling dynamics provide clear experimental signatures of this new cooling mechanism. The cooling rate can be changed by orders of magnitude by varying the amount of disorder which offers means for a variety of new applications that rely on hot-carrier transport.