Theory of passively mode-locked lasers for the case of a nonlinear complex-propagation coefficient (original) (raw)
1985, Journal of The Optical Society of America B-optical Physics
We examine passive mode locking, to which not only net-gain saturation but also group-velocity dispersion and self-phase modulation contribute significantly. Different sources of self-phase modulation are considered, and closed-form analytical solutions are obtained. The case of the colliding-pulse mode locking is discussed, and an ideal case is considered, in which the self-phase modulation and group-velocity dispersion are balanced so as to take maximum advantage of this additional shaping mechanism. This mechanism is shown to be similar to that which causes solitons in optical fibers; it provides additional reduction of the pulse width and significantly improves the stability against fluctuations in net gain.
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