The crystallinity and photoluminescence of sol-gel derived Nd/sup 3+/:LiNbO/sub 3/ thin films and powders

Summary form only given. Lithium niobate, LiNbO/sub 3/, is an attractive candidate for integrated optics (IO), because of its excellent electro-optical, acousto-optical, and nonlinear optical properties. Rare earth doping of LiNbO/sub 3/ will significantly increase the potential of this material. So far, Nd/sup 3+/ has been introduced into LiNbO/sub 3/ by direct crystal growth from doped melt, ion implantation and indiffusion, and recently pulsed laser deposition. We report the preparation and the characterization of sol-gel derived Nd/sup 3+/:LiNbO/sub 3/ thin films and powders. The host solution is prepared by mixing LiOC/sub 2/H/sub 5/ with Nb(OC/sub 2/H/sub 5/)/sub 5/ and Nd/sup 3+/ is introduced at different concentrations of 1%, 2%, and 3%mol. The thin films are deposited on SiO/sub 2//Si substrates by spin coating. The powders are prepared by calcinating the precipitation of the solution. The annealing temperature for all the samples is 500/spl deg/C. The trigonal phase of LiNbO/sub 3/ of the samples is identified by X-ray diffraction (XRD). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) studies reveal the multicrystalline nature of the films and the powders, with the crystalline size of about several tens of nanometers. An argon ion laser operating at the wavelength of 488 nm is used to excite the photoluminescence (PL) of the powders.