Abstract

Femtosecond pulses tunable in the 1.5-μm range have been generated by additive pulse mode-locking of the NaCl color-center laser by feeding part of the NaCl cavity output into a matched fiber cavity.¹ Additive pulse mode-locking (APM) also leads to the generation of stable ultrashort pulses in a wide variety of solid-state lasers. There has thus been considerable interest in the mechanisms responsible for APM. The APM NaCl laser is self-starting² and theoretical analyses of self-starting have been published recently.³ Here, we report an experimental study of the spectral dynamics leading to APM action in the NaCl laser, which shows unsuspected complexities.

© 1992 Optical Society of America