Broad-band amplification using a novel amplifier topology

A new broad-band amplifier topology that provides a continuous gain across 75 nm (1528-1603 nm) of optical bandwidth using Er/sup 3+/-doped SiO/sub 2/ fiber is demonstrated. The noise figure is low and does not present any discontinuity across the entire amplification bandwidth. The topology has a buried 1550/1585-nm splitter to reduce input signal loss and to provide amplified spontaneous emission suppression. The topology has been optimized using hybrid fiber; Er/sup 3+/-doped SiO/sub 2/ for the first stage and Er/sup 3+/-doped TeO/sub 2/ for the second stage, achieving 82 nm (1526-1618 nm) of optical bandwidth.