Nonlinear dynamic effects in a two-wave CO2 laser

Theoretical and experimental investigations were made of nonlinear dynamic regimes of the operation of a two-wave CO₂ laser with cw excitation in an electric discharge and loss modulation in one of the channels. Nonlinear amplitude — frequency characteristics of each of the laser channels have two low-frequency resonance spikes, associated with forced linear oscillations of two coupled oscillators, and high-frequency spikes, corresponding to doubling of the period of the output radiation oscillations. At low loss-modulation frequencies the intensity oscillations of the output radiation in the coupled channels are in antiphase, whereas at high modulation frequencies the dynamics is cophasal. Nonlinear dynamic effects, such as doubling of the period and of the repetition frequency of the pulses and chaotic oscillations of the output radiation intensity, are observed for certain system parameters.