The Peierls stress of interfacial dislocation under lattice mismatches

Abstract

The dislocation motion at heterointerfaces can be quantitatively predicted by estimating the Peierls barrier using the generalized stacking-fault energy surface. A simple formula is derived for the Peierls stress of misfit dislocations within the framework of the Peierls–Nabarro mechanism. This formula clarifies the correlation between a material’s yield strength, its elastic constant, and the dislocation structure, which is crucial for understanding the stability of heterointerfaces. Using the BAs/AlN heterojunction as an example, the validity of the energy barrier at the B–Al interface is confirmed through numerical results obtained from first-principles simulations.