Anisotropic GaAs island phase grown on flat GaP: spontaneously formed quantum wire array

A dense phase of GaAs wires forms in the early stages of strained growth on GaP,assembling from elongated Stranski-Krastanow islands. The electron diffraction during growth is consistent with long, faceted GaAs islands that are anisotropically deformed without dislocations. The lateral wire period and long shapes are not predicted by published models, though we conclude that the island orientation is picked out by facet energy inequivalencies not present in the analogous system of Ge islands on Si.