Measurement of the Electronic Thermal Conductance Channels and Heat Capacity of Graphene at Low Temperature

At ambient temperatures, graphene conducts heat via lattice vibrations called phonons, but at very low temperatures, electron-phonon coupling becomes weak and thermal conductance is mostly due to electron diffusion. High-sensitivity measurements across a wide temperature range provide new, state-of-the-art data on electron-phonon coupling, and reveal intriguing deviations from theoretical predictions regarding electron-based thermal and electric transport.