Thermal transport in defected armchair graphene nanoribbon: A molecular dynamics study

In this paper, we have performed equilibrium molecular dynamics simulation with the use of 2nd generation reactive empirical bond order (REBO) potential in order to characterize the thermal transport of defected armchair graphene nanoribbon (GNR) structures. Considering the fabrication perspective, we compute the thermal conductivity of defected armchair GNRs with several types of vacancies namely point vacancy, bi-vacancy and edge vacancy with varying defect concentration ranging from 0.5% to 3%. The estimated thermal conductivity for the defect structure is compared with that of pristine armchair GNR of similar size to analyze their possible correlations. At a defect concentration of 3%, thermal conductivity of defected armchair GNR experiences a reduction of ~80% from the pristine structure. Furthermore, we compare the thermal conductivity values of defected armchair GNR with its zigzag counterpart. Defected armchair configured GNRs show 40-60% smaller thermal conductivity in comparison with similar sized zigzag GNRs with vacancies. The variation of thermal conductivity with respect to width for the armchair configured defected GNRs is also studied. Such study would further encourage efficient and optimized thermal management in nano-thermal devices based on GNRs.