PULSING BEHAVIOR OF A 3-LEVEL LASER WITH SATURABLE ABSORBER

We present a numerical study of a three-level laser model that include s a saturable absorber. The theory models the laser as a lumped elemen t. This assumption is valid as long as the laser pulses are much longe r than the cavity. The model is intended to be somewhat representative of an erbium-doped fiber laser without trying to mimic the operating parameters of such a laser too closely. As expected, the presence of t he saturable absorber causes the laser to be unstable under certain op erating conditions. The question of stability is explored by examining small perturbations of the steady-state solutions of the rate equatio ns. We find that the predictions of this stability analysis are in exc ellent agreement with the behavior of the solutions of the full time-d ependent rate equations. Another result of this analysis is the realiz ation that under certain conditions the laser may pass from pulsed to stable operation simply by raising the pump power.