Abstract

There has been considerable recent interest in thulium-doped fiber (TDF) amplifiers for the S-band as a natural bandwidth extension in high-capacity WDM systems. Fluoride-based ZBLAN, the most efficient TDF platfonn, has the main disadvantage of host glass incompatibility with standard silica fibers and the resulting difficulty in fusion splicing, as well as mechanical and reliability issues. Additionally the position and relatively narrow width of the gain band make seamless S-C-band amplification more difficult to realize. Thus, other low-phonon energy glass hosts are being investigated to overcome these problems. A previous work reported 10-dB gain at 1480 mn and over 6-dB gain from 1460 to 1520 mn in 1 m of a fusion-spliceable Bi₂O₃-SiO₂-based TDF pumped with 1.2 W at 1047 mn and 23 mW at 1560 mn, demonstrating the potential for S-band amplification [1], Based on the gain enhancement effectiveness of an 800-mnband auxiliary pump in ZBLAN TDFs [2], we decided to investigate a similar Bi₂O₃-SiO₂-based TDF using 1050 mn+805 mn and 1426 mn+805 mn pmnping schemes.

© 2007 IEEE