NONLINEAR DYNAMICS IN A SINGLE-MODE 3-LEVEL LASER WITHOUT INVERSION

We characterize analytically the nature of the lasing solutions of a l aser operating without population inversion. We consider models involv ing three-level media interacting with a strong driving held and a las ing field in the vicinity of the lasing threshold. We assess the influ ence of different relaxation and pumping schemes on the dynamics of th ese lasers. We use the atom-field detuning, the cavity detuning, and t he linear gain as bifurcation parameters. Depending on their values, t he stable lasing solution is shown to be cw or self-pulsing. We show t hat the optimal lasing operation is achieved if both the driving held frequency and the cavity frequency are out of resonance with the atomi c frequencies. Physically, the lasing regimes arise from nonlinearly i nteracting sidebands induced in the lasing medium by atomic interferen ce. [S1063-651X(98)07201-8].