INTERACTION OF SELF-MODULATION AND RELAXATION OSCILLATIONS, AND ITS ROLE IN NONLINEAR DYNAMICS OF A SOLID-STATE RING LASER

Theoretical and experimental investigations were made of the frequency of relaxation oscillations and of the operational dynamics of a solid -state ring laser when the frequency of self-modulation oscillations w as varied within a wide range by altering one of the feedback coeffici ents of counterpropagating waves. The generally accepted formula for t he relaxation frequency omega(r) [(omega/Q) eta/T-1](1/2) is valid onl y in the limited range of self-modulation oscillation frequencies; her e, (omega/Q) is the cavity bandwidth, eta is the excess above the pump ing threshold, and T-1 is the relaxation time of the population invers ion. A strong interdependence of the frequencies of self-modulation an d relaxation oscillations, as well as mutual locking of these frequenc ies in the region of a parametric resonance were observed. Period doub ling of self-modulation oscillations and dynamic chaos were investigat ed in the region of a parametric resonance between self-modulation and relaxation oscillations.