Self-Replicating Twins in Nanowires

Based on molecular-dynamics simulations validated with quantum-mechanical calculations, we predict that (111) twin planes in a [111]-oriented GaAs nanowire attain attractive interactions mediated by surface strain. This gives rise to a self-replication mechanism that continuously generates a twin superlattice in a nanowire during growth. We demonstrate significant implications of the twin twin interaction for the electronic, mechanical, and chemical properties of nanowires. These unique properties suggest potential applications such as catalysts for solar fuel production and nanoscale mechanical dampers.