Tunable, gain-clamped EDFA incorporatingchirped fibre Bragg grating

Abstract

A new technique for tuning the gain of a gain-clamped erbium-doped fibre amplifier is presented. It uses a chirped fibre grating (with linear slope reflectivity) and a narrowband uniform grating to form the laser cavity. By strain tuning the input narrowband grating, the laser feedback is varied and the amplifier inversion and gain can be controlled. This technique provides a continuous gain tuning capability, together with clamped gain operation.