Abstract

One of the most important sources of ultrashort pulses are lasers that are passively mode-locked with the help of the optical Kerr nonlinearity. One may employ a nonlinear resonator, coupled to the main resonator to achieve short pulses; this is known as coupled cavity or additive pulse modelocking (APM). However, it is well known that nonlinear resonators are prone to unstable behavior and chaos. In fact, Sucha et al. [1] reported on period doubling and quasi-periodicity in an APM color center laser. It is also noteworthy that an APM laser is most closely related to a driven passive fiber ring in which the ocurrente of rich deterministic dynamics has been established [2]. This may raise doubt whether APM lasers can provide the high stability of the pulse train required for most applications. Only an understanding of its unstable behavior can provide guidelines to reliably obtain stable pulses.

© 1996 IEEE