Preparation and waveguiding properties of sol-gel derived lathanum modified lead titanate slab waveguides

Using sol-gel processing method, thin films of lathanum modified lead titanate (PLT) on Corning 7059 glass were prepared. Differential thermal analysis (DTA/TG) curve of gel powder and infrared spectra (FT-IR) of the films were measured to estimate proper heating schedule. Microstructures of the films were observed using a scanning electron microscope (SEM). The waveguiding properties and the propagation loss were measured using the prism coupling method. Effects of the drying conditions on the refractive indices and the propagation losses of the films were investigated. Experimental results showed that the grain size and the content of residual organics in the film decreased as the drying temperature of the film increased. As the drying temperature increased, the refractive index increased and the propagation loss decreased.