Gain-flattened tellurite-based EDFA with a flat amplification bandwidth of 76 nm

Abstract
We describe a tellurite-based Er/sup 3+/-doped fiber amplifier (EDFA) with a flat amplification bandwidth of 76 nm and a noise figure of less than 7 dB. Furthermore, a parallel-type amplifier composed of this EDFA and a 1.45-μm-band Tm/sup 3+/-doped fluoride fiber amplifier achieved a flat amplification bandwidth of 113 nm.