Non radiative relaxation rate modification by chlorine codoping of rare earth activated PZG fluoride glasses

摘要

The luminescence of rare earth ions Re~(3+) = Pr~(3+), Er~(3+), and Tm~3 in PZG fluoride glass (36PbF_2-24ZnF_2-35GaF_3-5YF_3-2AlF_3 in mol%) doped with ReCl_3 was investigated. This study was initiated in the perspective of realizing by vapor phase deposition (PVD) rare earth activated fluoride glass channel waveguides acting as integrated optical amplifiers, ReCl_3 being more volatile than the fluoride counterpart. The results were compared to the spectroscopic properties of ReF_3-doped PZG glasses. For phonon-sensitive radiative transitions, the lifetime was prolonged at low ReCl_3 concentration because of phonon energy and/or electron coupling are reduced. For Pr~(3+), the doping with PrCl_3 increases the lifetime by 50% in respect to PrF_3 doping. These results suggest that the chlorine ions remain in the coordination sphere of the rare earth ions in the ReCl_3-doped glass after melting. The luminescence decay of Er~(3+): ~4I_(13/2) level in ErCl_3-doped channel waveguides is also discussed.