The dislocations in graphene with the correction from lattice effect

摘要

The dislocation widths and Peierls stresses of glide dislocations and shuffle dislocations in graphene have been studied by the improved Peierls-Nabarro (P-N) equation which contains the discrete correction. The discrete parameter is obtained from a simple dynamic model in which the interaction attributed to the variation of bond length and angle was considered. The restoring force in the improved P-N equation is given by the gradient of the generalized stacking fault energy surface (γ-surface). Our calculation shows that the widths of the shuffle dislocation and the glide dislocation are narrow and the width of the shuffle dislocation is about twice wider than the glide dislocation. The Peierls stress of a shuffle dislocation is one order of magnitude smaller than that of a glide dislocation. As a consequence, the shuffle dislocation moves more easily than the glide dislocation.