Optical properties of erbium and thulium co-doped in tellurite glasses for the S+C band optical amplification

摘要

Optical spectroscopic properties of Er~(3+) and Tm~(3+) ions in new niobium tellurite glasses, TeO_2-BaO-SrO-Nb_2O_5 (TBSN), were investigated for (S+C)-band optical amplifications. On the basis of consideration for cross-relaxation among Tm~(3+) ions and multi-phonon relaxation, it was shown that the presence of Nb_2O_5, which was source of the highest energy phonon, contributed to relaxation processes in TBSN glasses. The C-band amplification transition for Er~(3+) and the S-band amplification transition for Tm~(3+) are both sufficiently efficient in TBSN glasses and the Er~(3+)-Tm~(3+) co-doped TBSN fibers could be efficient seamless (S+C)-band amplification media by selecting the concentrations of Er~(3+) and Tm~(3+)