Cladding-pumped erbium-doped fiber amplifiers for low noise high-power WDM and analog CATV boosters-new design using ring-doping

Summary form only given. Fibers with ring-doped gain media have been suggested for high-inversion operation of cladding-pumped fibers. Ring-doping locates the erbium in a ring around a single-mode core. In the ring, the signal intensity can be comparatively low even for high signal powers, while the pump intensity is approximately constant throughout a cross section of the fiber. Ring doping thus facilitates high population inversions at high signal powers. We show through computer simulations how this improves the output power of cladding-pumped EDFAs for WDM and analog community antenna television (CATV) applications.