Lasing in ZnS nanowires grown on anodic aluminum oxide templates

High-density and uniform-sized gold particle arrays have been prepared electrochemically on anodic aluminum oxide (AAO) templates. The gold particles were used as catalysts to synthesize ZnS nanowires. The as-grown nanowires had a wurtzite single-crystal structure and were aligned perpendicularly to the AAO template. Under high-power density optical excitation (266nm), the nanowire array showed an intense, narrow [full width at half maximum (FWHM) of 2.2nm] photoluminescent peak at 338nm composed of a superposition of optical resonant modes (FWHM ∼0.3nm) resulting from the collective emission of a large number of nanowires. These results indicate that the ZnS nanowires act as optical waveguide resonators.