Observation of quantum confined excited states of GaN nanocrystals

GaN nanocrystals with an average diameter of 4.5 nm+/-1.6 nm were synthesized by pulsed laser ablation of a gallium metal target in a nitrogen atmosphere. Transmission electron microscopy and selected area electron diffraction confirmed the hexagonal structure and size of the nanocrystals. Optical absorption and photoluminescence spectroscopy revealed quantum confined excited states in the nanocrystalline samples with features at 4.43 eV (280 nm) and 5.47 eV (227 nm), (C) 1998 American Institute of Physics.