Comparison between standard and modified Judd-Ofelt theories in a Pr3+ doped fluoride glass

A method which takes into account normalized oscillator strengths is detailed for the calculation of parameters in Judd-Ofelt theory. In the case of Pr3+ - doped fluorozirconate glass, the Judd-Ofelt parameters obtained in this way do not depend strongly on the transitions induced in the fit. Particularly, it is no longer necessary to exclude the 3H4→3P2 transition from the analysis. The modified theories are also considered but do not improve the calculated intensities when the energy of the 5d level is set to its experimentally determined value. Finally, in connection with 1.3 μm amplification, the 1.3μ reabsorption (1G4→1D2) oscillator strength is computed from the various models as well as the 1.3 μm emission branching ratio (1G4→3H5/1G4→3H6). The best agreement with experiment is obtained with the Judd-Ofelt theory. (author)