▎ 摘　　要

Graphene-metal nanocomposites are promising materials to address the heat dissipation problems in nanoscale electronic and computing devices. A low resistance interface between metal and graphene contact is crucial for the development of highly efficient nanodevices. In this direction, we have investigated the thermal conductance (TC) across the gold-graphene interface for various thicknesses of the graphene layer and temperatures using molecular dynamics (MD) simulations. The TC is found to decrease with the increase in graphene layer number from one to three. Further increase in the number of layers has no effect on the TC. The TC is also found to increase monotonously with the temperature in the range from 50 to 300 K. However, there is no effect of temperature on TC beyond 300 K. In order to enhance the TC value, we have investigated the thermal transport in the defect mediated gold-graphene interface for various defect sizes and defect densities. TC is found to increase significantly with the increase in the vacancy defect size and density of defects in the graphene sheet. The TC obtained for graphene containing defects of size 2.24 and 3.16 angstrom at 300 K is found to be 5 and 26% higher than the TC obtained for defect free graphene. The vibrational density of states (VDOS) of interface forming materials shows that the defects in the graphene sheet enhance the out-of-plane low frequency vibrational modes within graphene. This process facilitates high vibrational coupling between the gold and graphene, and enhances the heat transfer across the interface. This demonstrates that the TC across the gold-graphene interface can be tuned by adjusting the defect vacancy size and density of the defects.