Structure and optical properties of rare earth doped Y2O3 waveguide films derived by sol–gel process

Abstract Pure and rare earth ions doped yttrium oxide (Y2O3) waveguide films were prepared by a simple sol–gel process and dip-coating technique. Y2O3 were successfully synthesized by hydrolysis of yttrium acetate. The structural evolution of Y2O3 films with annealing temperature was investigated by X-ray diffraction, Fourier transform infrared spectroscopy, waveguide Raman spectroscopy and High-resolution transmission electron microscopy. The propagation loss of Y2O3 thin films at 632.8 nm measured by scattering-detection method is approximately 1.5 dB/cm. The fluorescence of Er3+ and Eu3+ doped Y2O3 waveguide thin films were studied under the waveguide configuration. The fluorescence intensities evolution with annealing temperature of Y2O3:Er3+ films has been studied and was explained by the multi-phonon non-radiative processes. Our results show that Y2O3 is a good host material for optically active waveguide thin films and sol–gel process is a useful method to derive pure and doped Y2O3 waveguide films.