Photovoltaics with piezoelectric core-shell nanowires
We report on the discovery of a generic piezoelectric field in strained core-shell compound semiconductor nanowires. We present the lattice-mismatch induced strain in epitaxial core-shell nanowires and show that it gives, very generally, rise to an internal piezoelectric field along the axis of the nanowire. This field results predominantly from atomic displacements in polar bonds and microscopic