The energy barriers predicted by continuum mechanics models for homogeneous dislocation nucleation in copper were compared with explicit atomistic calculations. It was found that a relatively simple continuum model could agree with full atomistic calculations if the dislocation Burgers vector was allowed to increase continuously during nucleation. The analysis identifies the significant effect of the applied shear stress on the generalized stacking fault energy and leads to a more physical definition of the ideal shear strength.

Energy Barrier for Homogeneous Dislocation Nucleation: Comparing Atomistic and Continuum Models. S.Aubry, K.Kang, S.Ryu, W.Cai: Scripta Materialia, 2011, 64[11], 1043-6