Characteristics of ultraviolet photoluminescence from high quality tin oxide nanowires

We investigate the optical properties of ultraviolet range emission from high quality tin oxide nanowires prepared by vapor-liquid-solid growth technique. Temperature dependent photoluminescence (PL) measurement is performed between 10 and 300 K. At low temperatures, the PL originates from radiative recombination of excitons bound to neutral donors, donor-acceptor pair transition and their associated longitudinal optical (LO) phonon replicas. The LO-phonon replicas up to third order with Huang-Rhys factor of 0.34 are observed. Evolution of the peaks and the origin of PL thermal quenching at high temperatures are discussed in detail.