Spectroscopic properties of Tm3+ ions in PbO–PbF2–Bi2O3–Ga2O3 glasses for S-band optical amplifications.

The spectroscopic properties of Tm3+ ions in (57-x)PbO–xPbF2–25Bi2O3–18Ga2O3 (mol %) glasses were investigated through measurements of absorption, emission, and lifetime measurements. The PbF2 substitution in this glass system raised the lifetime of the 1.48 μm emission. The lifetime for the 3H4 level was changed from 272 to 416 μs when the PbF2 content increased from x=0 to 15. In a 47PbO–15PbF2–25Bi2O3–18Ga2O3 glass, the phonon-assisted energy transfer involving two phonons with the energy of 550 cm-1 dominated the cross relaxation of the Tm3+: 3H4, 3H6→3F4, 3F4 route in spite of the presence of the overlap between the 3H4→3F4 emission and 3H6→3F4 absorption spectra. As a result, PbO–PbF2–Bi2O3–Ga2O3 glasses were thought to be useful for the S-band optical fiber amplifiers. [ABSTRACT FROM AUTHOR]