Enhancement and quenching of ZnO nanowire luminescence by electron irradiation.

Electron microscopy is an essential tool in the fabrication and characterization of optoelectronic devices. This study systematically investigated the stability of zinc oxide nanowires under electron irradiation, focusing on spontaneous and stimulated emission as well as their waveguiding properties. Spontaneous emission initially increases, which we attribute to the desorption of surface species, leading to a reduced surface band bending and enhanced luminescence. However, continued electron irradiation results in hydrocarbon formation on the nanowire surface, increasing waveguiding losses. These increased optical losses, in turn, raise the lasing threshold of nanowire lasers. Our findings offer valuable insights into the electron imaging parameters for optimizing semiconductor nanowires in optoelectronic applications.