Abstract

We report on the bifurcation structure of a gain modulated two-mode solid state laser in a Fabry-Perot configuration. We concentrate on the good cavity limit, and we use the rate equations that describe the interaction between the population inversion (including the influence of hole burning) and the photon dynamics. The unforced problem allows in its transient behavior for a new oscillation frequency that is much lower than the relaxation oscillation frequency. Our aim is to explain the lasing mode dynamics through the interplay between these two frequencies. We analyze the response of the laser as a function of the modulation frequency. We differentiate between the cases of small and deep modulation. In the former case, the bifurcation diagram exhibits resonance behavior in the vicinity of the two internal frequencies as well as regions of multistability. In the latter case, where the modulation brings the laser below the second threshold (the one that signifies the onset of the two-mode solution) for part of the cycle, a rich bifurcation structure has been found with regions of multistability, period doublings, bifurcations to torus, and chaos. In the case of multistability, the fine structure for each branch of periodic solutions can be related to the two frequencies.

© 1992 Optical Society of America