BaTiO_3 Thin Films for Electro-optic and Non-linear Optical Applications

摘要

Er-doped BaTiO_3 thin films have been investigated as a candidate for an optically active waveguide medium. Epitaxial layers were prepared by metal-organic chemical vapor deposition at low pressure. The properties of the characteristic Er~(3+) luminescence transition at 0.8 eV have been investigated for epitaxial Er doped BaTiO_3 thin films for various Er concentrations. The photoluminescent intensity was found to increase by a factor greater than 500 when the doping level was increased from 1 X 10~(20) cm~(-3) to 2.2 X 10~(21) cm~(-3), indicating that concentration quenching was not significant at the highest doping levels. A complex emission spectra was observed and was attributed to the multi-site substitution of Er in BaTiO_3. Transient decay measurements revealed a 7 ms radiative lifetime for the 0.80 eV transition that was independent of concentration.