Evaluation of local field effect on the 4I13/2 lifetimes in Er-doped silica-hafnia planar waveguides

A series of (100-x) SiO2-xHfO(2) planar waveguides (10 < x < 45) doped with 0.01 mol % Er3+ was prepared by a sol-gel route. The lifetime of the I-4(13/2) level and the refractive index of the waveguides were measured. The magnetic dipole and electric dipole rates of the I-4(13/2)-> I-4(15/2) transition were estimated as a function of the refractive index. The electric dipole transition rates were well reproduced by the real cavity model.