Behavior of a CO2 laser under loss modulation: critical analysis of different theoretical models

Abstract Various theoretical rate equation models describing the dynamics of the CO 2 laser are developed and analysed. In the frame-work of these models, the response of a CO 2 laser subjected to cavity loss modulation is investigated. A critical analysis of these descriptions is performed by comparison with experimental data. It is shown that both the so-called two- and three-level models are inadequate to reproduce, even qualitatively, the experimental data. On the other hand, the four-level model which includes the rovibrational level manifolds fits the experiments correctly.