On the importance of collective excitations for thermal transport in graphene

摘要: We use equilibrium molecular dynamics (MD) simulations to study heat transport in bulk single-layer graphene. Through a modal analysis of the MD trajectories employing time-domain formulation, we find that collective excitations involving flexural acoustic (ZA) phonons, which have been neglected previous studies, actually dominate flow, generating as much 78% flux. These are, however, less significant if atomic displacements are constrained lattice plane. Although relaxation is slow, graphene be regular (non-anomalous) conductor for sample sizes order 40 μm and more.