TeO -Based Glasses Containing Nb O ,T iO , and WO for Discrete Raman Fiber Amplification

AMAN amplifiers offer a valuable solution to extend the use of the present and future (in OH-free fibers) communication windows in wavelength-division-multiplexing (WDM) systems, as they are not intrinsically limited to specific wavelength ranges of amplification as Er-doped fiber amplifiers. While distributed Raman amplification within the transmission fiber offers several advantages from the system point of view, it is not suitable for applications such as the local compensation of the insertion losses of the WDM functions. Therefore, discrete Raman amplifiers are needed. State of the art Raman fibers are mainly based on silica and doped silica glasses. Unfortunately, these glasses present poor performance in terms of Raman gain and amplification bandwidth. Mori et al. presented an ultrawide-band and discrete Raman amplifier based on tellurite fibers [1], [2], featuring a fiber loss of 20.4 dB/km at 1560 nm and . The Raman gain