A nanowire-based device and method employ removal of residual carriers. The nanowire-based device includes a semiconductor nanowire having a semiconductor junction, and a residual carrier sink. The residual carrier sink is located at or adjacent to the semiconductor nanowire near the semiconductor junction and employs one or both of enhanced recombination and direct extraction of the residual carriers. The method includes providing a semiconductor nanowire, forming a semiconductor junction within the semiconductor nanowire, forming a residual carrier sink, and removing residual carriers from the semiconductor junction region using the residual carrier sink.