Abstract

AM mode-locking is very sensitive to the loss modulation frequency. The laser emits trains of mode-locked pulses when the duration of a round trip through the cavity is matched to the period of the modulator. However, very little detuning from the optimum frequency results in instabilities and relaxation oscillations. A stability analysis has been conducted within the framework of the Kuizenga-Siegman model.¹ According to this model, the stationary field created by the mode-locking process is a chirpless Gaussian pulse whose spectrum is centered on the peak of the homogeneous line. The pulse duration can be analytically predicted in terms of the laser parameters. The stability of this equilibrium solution was evaluated analytically as well as numerically regarding the shown that the correlation bandwidth obtained by pumping rate was assumed, and inversion decay was taken into account. Contrary to what has been done until now,² our work considers the effects of nonzero chirp and carrier frequency perturbations on the process. It is shown that these can make the chirpless solution unstable for positive detuning. A stable solution with a sizable chirp has also been obtained.

© 1987 Optical Society of America