Dynamics of the competition between opposite waves in a ring laser

An experimental investigation was made of the competition between the opposite waves in an He–Ne ring laser emitting radiation at λ = 3.39 μ. There was a considerable change in the nature of the competition when the emission frequency was modulated. The depth of the dip in the dispersion curve of the wave intensity decreased considerably when the modulation frequency was increased. An investigation was made of the dependences of the observed effects on the difference between the bands of the opposite waves in the ring resonator and on the degree of coupling between these waves. The amplitude equations were solved numerically and a qualitative agreement was obtained between the theory and experiment.