Effect of composition and morphology on the spectral properties and stability of dyes doped in a sol-gel glass waveguide

Planar waveguides made of titania and organically modified silica (osmosil) and doped by laser dyes were prepared using the sol-gel method. The film structure and morphology were studied using absorption spectroscopy in the UV and by atomic force microscopy (AFM). The size of the titania nanoparticles was determined from the increase in the energy gap between the valence and conduction bands calculated from the UV absorption spectra. The filmsʹ morphology was studied from the AFM images. The doped dye molecules are in the organic phase of the hybrid glass, the fluorescence yield and photostability increase with the oemosil content of the glass; those trends are connected to the decrease in the film pore size.