Suppression of Excited State Absorption in Erbium-doped Bi₂O₃-GeO₂-Ga₂O₃-Na₂O Glasses

The Ce~(3+) ions and B_2O_3 component were introduced into the Er~(3+)-doped Bi_2O_3-GeO_2- Ga_2O_3-Na_2O glasses,respectively.And the suppression of excited state absorption of Er~(3+):~4I_(11/2) level was investigated under the excitation of 975nm LD.With the introduction of Ce~(3+) ion or B_2O_3 com- ponent,the energy transfer between Er~(3+):~4I_(11/2) and Ce~(3+):~2F_(5/2) levels or the multi-phonon relaxation rate of Er~(3+):~4I_(11/2)→~4 I_(13/2) increase,respectively,and the excited state absorption is suppressed effi- ciently owing to the evident decrease of ~4I_(11/2) level fluorescence lifetime.Meanwhile,the results show that the total quantum efficiency of Er~(3+):~4I_(13/2)→~4I_(15/2) is enhanced in the case of Ce~(3+) ion doping, and the fluorescence intensity of 1.55μm radiative transition is improved accordingly while its effective spectral width is almost unchanged.In the case of B_2O_3 component introduction,although the 1.55μm fluorescence intensity is somewhat weakened,its effective spectral width is further broadened and the peak wavelength of gain cross-section shifts to longer wavelength region.