Stimulated luminescence of ZnO nanocrystals of different shape grown by the method of gas transport (original) (raw)

The influence of shape and size of zinc oxide nanocrystals on threshold and directionality of lasing in the UV spectrum region is investigated. Columnar-shaped nanocrystals with a hexagonal faceting are shown to have a minimal threshold of the optical excitation power for nanoresonator diameters of 100-200 nm comparable with the absorption length of the exciting light. The mode structure of the laser emission directed preferentially along the axis of hexagonal prisms is observed. Different lasing mechanism is established for nanocrystals shaped as prisms or pyramids with a hexagonal base. High homogeneity in shape and a size of ZnO nanocrystals, and the dependence of these parameters on gas transport synthesis conditions are established by methods of electron microscopy.