Enhanced spectroscopic properties at 1.5 μm in Er~(3+)/Yb~(3+)-activated silica-titania planar waveguides fabricated by rf-sputtering

摘要

Er~(3+)/Yb~(3+)-codoped 94SiO_2-6TiO_2 planar waveguides, with 1 mol% Er and molar ratio Yb/Er =2, were fabricated by rf-sputtering technique. All waveguides were single-mode at 1550 nm. An attenuation coefficient of 0.5 dB/cm at 632.8 nm and a lifetime of the ~4I_(13/2) metastabile state of 7.2 ms were measured. Upon cw excitation at 978 nm, an increase of the 1.53 μm luminescence intensity larger than two-fold was detected in the Yb~(3+)/Er~(3+)-codoped waveguide with respect to the waveguide doped only with Er~(3+).