The energy of a dislocation within a coherently strained nanostructure was calculated as a function of misfit and position. If the misfit was decreased below a critical value, no energetically stable position for the dislocations exists inside the island. This instability was understood in terms of a simple two-dimensional model and it was proposed that this could lead to motion of the nanostructure across the surface via a novel crawl mechanism.

Critical Misfit for Dislocation Stability in Self-Assembled Islands. U.Denker, D.E.Jesson: Physica Status Solidi B, 2005, 242[12], 2455-61