Long-term dynamic stability of discrete dislocations in graphene at finite temperature

摘要

We present an assessment of the finite-temperature dynamical stability of discrete dislocations in graphene. In order to ascertain stability, we insert discrete dislocation quadrupole configurations into molecular dynamics calculations as initial conditions. In calculations we use Sandia National Laboratories Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) and the Adaptive Intermolecular Reactive Empirical Bond-Order (AIREBO) potential. The analysis shows that the core structures predicted by discrete dislocation theory are dynamically stable up to temperatures of 2,500 K, though they tend to relax somewhat in the course of molecular dynamics. In addition, we find that discrete dislocation theory accurately predicts energies, though it exhibits a slight overly-stiff bias.