THERMALLY POLED SILICATE THIN-FILMS WITH LARGE 2ND-HARMONIC GENERATION

Ge- and Ti-doped silica thin films were prepared upon various substrat es by solgel processing and rf sputtering. Large second-harmonic gener ation was measured from thermally poled thin-film samples. The origin of nonlinearity and its distribution from thermally poled silicate thi n films were investigated. Moreover, we measured the stability of the nonlinearity of a rf-sputtered germanosilicate thin film upon a silica glass substrate against heat and intense laser light sufficient for t he fabrication of waveguide-type nonlinear optical devices. (C) 1998 O ptical Society of America.