Re-evaluating the applicability of Peierls–Nabarro models for GaAs: A strain-based criterion

Abstract

Classic Peierls–Nabarro (PN) model is widely regarded as inadequate for estimating Peierls stress in ceramics and semiconductors, driving the development of improved variants such as the D-PN and local misfit energy (LME) models. However, we find that this view does not apply to GaAs. This work establishes a strain-based criterion for determining the applicable conditions of different PN models. Using the 1/2[1¯10](111) screw dislocation in GaAs as the research system, we apply both the classic generalized stacking faults (GSF) model and the LME model to calculate the restoring force and solve the PN equation. LME simulations reveal that an inelastic strain dominates the shear process of a [1¯10](111) slip system, satisfying the conditions for the classic GSF model. The Peierls stress predicted by the GSF model exhibits good agreement with the experimental data. These results demonstrate that the classic model remains effective when the dislocation core is dominated by the inelastic strain. In contrast, introducing excessive elastic strain via improved models yields unphysical predictions. This work provides a practical protocol for selecting the appropriate PN model to simulate dislocations in ceramics and semiconductors.