Abstract

Simultaneous operation of passive and active mode-locking of the erbium-doped fibre lasers (EDFAs) has been attempted to utilise the short pulse mechanism of the passive mode-locking scheme and the relatively high repetition rate operation and easy pulse synchronisation mechanism of the active mode-locking scheme at the same time [1-6], In this paper we describe the experimental performance and a theoretical analysis of the hybrid-type actively and passively mode-locked EDFL in a figure-of-eight geometry with a nonlinear amplifier loop mirror (NLAM) and a directional-coupler type electro-optic modulator for the optimum operating conditions.

© 1996 Optical Society of America