Thermal Conduction in Suspended Graphene Layers

We review the results of our experimental and theoretical investigation of heat conduction in suspended graphene layers. Through direct measurements using a noncontact optical technique, we established that the thermal conductivity of the suspended graphene flakes is extremely high, and exceeds that of diamond and carbon nanotubes. By invoking Klemens' theoretical model, we explained the physical mechanisms behind such unusual thermal conduction in two-dimensional graphene layers. Our detailed theory, which includes the phonon-mode dependent Gruneisen parameter and takes into account phonon scattering on graphene edges and point defects, gives results in excellent agreement with the measurements. Superior thermal properties of graphene are beneficial for all proposed graphene device applications.