Optical properties of Au and Pt-doped PLT 28 films

Metal colloid-doped oxides yield potentially interesting non-linear optical properties especially third order non-linearity which is expected to be enhanced in oxide matrices with high values of dielectric constant or refractive index. La-doped PbTiO₃ (i.e. PLT 28) films, incorporated with 0.05 to 2 mole % Au and Pt, were obtained using sol-gel deposition techniques. The films were spincoated on Corning 7059 glass substrates and fired at 400°C-600°C. The films were then subjected to optical characterization, namely transmission and absorbance spectroscopy. PLT films doped with Au appeared bluish which turned deeper with higher Au concentration or higher firing temperatures. Additionally, the absorbance peak (near 650 nm) shifted to shorter wavelengths with higher metal colloid contents but shifted to longer wavelengths at higher firing temperatures. The waveguiding loss in the Pt-doped films ranged from 2-3 dB/cm