Optical properties of and concentration quenching in Bi2O3–B2O3–Ga2O3 glasses

Er2O3-doped Bi2O3–B2O3–Ga2O3 glasses were prepared by the conventional melt-quenching method, and the Er3+:4I13/2 → 4I15/2 fluorescence properties are studied for different Er3+ concentrations. when the Er2O3 concentration increases from 0.03 to 3.0 mol%, the measured lifetime of Er3+:4I13/2 level decrease from 2.24 to 0.9 m s, and from 0.25 to 0.20 m s for the Er3+:4I11/2 level. The fast energy migration among Er3+ ions cause the reduction of lifetime of the 4I13/2 level, whereas the change in the 4I11/2 level is mainly due to a cooperative upconversion process (4I11/2, 4I11/2) → (4F7/2, 4I15/2). Based on the dipole–dipole interaction theory, the interaction parameter, CEr,Er, for the migration rate of Er3+:4I13/2 ↔ 4I13/2 was calculated to be 32 × 10−40 cm6 s−1.