Study of the effect of intracenter and cross-relaxation transitions on the efficiency of 1.54-μm luminescence of Er3+ ions in ZBLAN glass

Mechanisms underlying the effect of Tb3+ and Eu3+ ions on the efficiency of 1.54-μm luminescence of Er3+ ions in ZBLAN glass were studied. The cross-relaxation coefficients were measured. The ion-ion interaction channels considered were used to construct coupled balance equations describing the variation in ion level population. The optimum concentrations of the dopants were found. The experimental data obtained and theoretical estimates evidence the possibility of increasing the population of the 4 I 13/2 state of the Er3+ ion, which would enable development of more efficient erbium-based amplifiers in the case of excitation at the wavelength of 0.975 μm.