Chaos in a Four-Frequency Class-A Laser With Linear Coupling of Elliptically Polarized Eigenstates

Abstract

From the beginning of the age of laser dynamics, understanding the pole of complicated (chaotic and stochastic) oscillations has been radically changed. The routes to asymmetric and symmetric chaos have been elucidated in a four‐frequency ring gas class‐A laser (FRGL) with linear coupling between the counterrunning elliptically polarized waves. A theoretical model of this laser has been developed on the basis of Jones vectors and matrix formalism, which in the case of linearly polarized waves confirmed all regimes of lasing observed in the experiment. The diagram of attractors has been calculated on the plane of the absolute value of the coefficient of backscattering, r, and the frequency detuning from the center of the gain profile, x. Several types of regimes have been found: one‐ and two‐frequency standing waves; two‐ and four‐frequency traveling waves; periodic regimes corresponding to symmetric and asymmetric limit cycles, as well as noise‐sensitive operation. Symmetry properties of the model have been elucidated. At small values of r, a noise‐sensitive operation has been revealed. Thus, in a FRGL with elliptically polarized eigenstates, the following complicated oscillations have been found: (i) asymmetric chaos, arising through a period‐doubling bifurcation cascade of an asymmetric limit cycle, accompanying the pitchfork‐bifurcation of a periodic solution; (ii) asymmetric chaos, arising as a result of interaction of two asymmetric chaotic attractors; (iii) noise‐induced stochastic oscillations; (iv) asymmetric chaos, arising at stochastization of an asymmetric limit cycle of the second kind; and (v) symmetric chaos, arising through the loss of stability of a symmetric limit cycle and intermittency.