Gain-shifted dual-wavelength-pumped thulium-doped fiber amplifier for WDM signals in the 1.48-1.51-mu m wavelength region

We constructed a gain-shifted dual-wavelength-pumped (1.05/1.56 mum) thuliu m-doped fiber amplifier (TDFA) for wavelength-division-multiplexing (WDM) s ignals in the 1.48-1.51-mum wavelength region, We obtained a gain of larger than 20 dB and a noise figure of less than 7 dB in the range from 1478 to 1505 nm, Amplifier saturated output power was +20.1 dBm with an optical-to- optical conversion efficiency of 9.1% for 12-channel WDM signals. We also o btained a successful bit error rate performance for signals modulated at 10 Gb/s when the gain-shifted TDFA was used in an optical preamplifier config uration. These results confirm the feasibility of using the gain-shifted TD FA as both a booster and an optical preamplifier in WDM networks.