Parametric processes and multistability in a ring chip laser with periodic pump modulation

The first detailed experimental and theoretical investigation is reported of the influence of periodic pump modulation on a type 1 self-modulation in a ring Nd:YAG chip laser pumped by a semiconductor laser diode. It is shown that the excitation of relaxation oscillations as a result of parametric processes and direct resonant action of pump modulation has a significant influence on the lasing regimes, on the temporal and spectral characteristics of the output radiation, and on the scenario of a transition to chaos. It is shown that for the same laser parameters there may be two coexistent lasing regimes, including quasiperiodic operation of two types. The lasing regimes are classified and the ranges of their stability are investigated for varying modulation frequency and depth.