Gain flatness comparison between erbium-doped fluoride and silica fiber amplifiers with wavelength-multiplexed signals

Abstract

With the ever growing interest in wavelength division multiplexing transmission systems, the need for an optical amplifier with a large bandwidth is more and more necessary. Unlike the standard erbium-doped silica fiber amplifiers, the fluoride-based fiber amplifiers display more uniform gain spectra. The benefit expected from fluoride amplifiers with multiwavelength signals has been experimentally assessed through comparisons in single- and cascaded-amplifiers configurations. Four db gain flatness was achieved with four wavelength-multiplexed signals extending over 23 nm after three fluoride amplifiers while 15 dB gain unbalance was observed after three silica amplifiers. This result shows that fluoride amplifiers may be of the utmost relevance for multiwavelength transport systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>