Wide Band Erbium-Doped Fluoride Fiber Optical Amplifier at 2.7 µm with Fluoride Fiber Wavelength-Division Multiplex Coupler

A 2.7 µm band optical amplifier composed of an erbium doped fluoride fiber and a low loss fluoride fiber wavelength-division multiplex (WDM) coupler is reported. A maximium gain of 35.9 dB was obtained. An optical gain of more than 20 dB was obtained over a 90 nm wavelength range from 2.72 to 2.81 µm with a pump of 200 mW at 0.647 µm. The saturation output signal power was -2 dBm, and was independent of the pump power.