The influence of the secondary electrooptic effect on the generation of lasers with a negative feedback

The results of an experimental study of ruby and neodymium lasers with a negative electrooptic feedback are discussed. It is shown that in such lasers, the piezooptic effect leading to the amplification of power fluctuations at frequencies close to the resonance frequencies of the electrooptic crystal is responsible for the suppression of the quasi-continuous lasing mode. The above mechanism is effective at negligibly small delays of the feedback signal. The parameters of the negative electrooptic feedback system which would result in stable quasi-continuous laser action over a wide range of excitation characteristics are determined, as are the conditions for regular pulsations.