Abstract

Passive mode locking of fiber lasers in the figure-eight ¹ and the ring ² configuration have been reported. Coupled-cavity mode locking of fiber lasers by using bulk optics has also been reported.³ We report, for the first time to our knowledge, the generation of very stable mode-locked laser pulses from an in-line coupled-cavity fiber laser by using three intracore Bragg gratings. The theory of passive mode locking is well understood.^4-6 Using the nonlinear model of a coupled cavity with a nonlinear index, we constructed two in-line coupled-cavity fiber lasers, both of which used Er-doped fiber as main laser cavity and a nonlinear silica fiber of the same length as the auxiliary cavity. Two intracore Bragg gratings were used to form the main cavity, and a third intracore Bragg grating was used to form the coupled cavity.

© 1995 Optical Society of America