SPATIOTEMPORAL DYNAMICS OF COUPLED-TRANSVERSE-MODE OSCILLATIONS IN UNIDIRECTIONAL PHOTOREFRACTIVE RING RESONATORS

We examine the spatiotemporal dynamics of the optical field that arises from two-wave mixing in a multiple-transverse-mode unidirectional photorefractive ring resonator. Using the passive resonator's transverse modes as a basis, we derive a set of differential equations that describes the mode dynamics when both pump-mode and mode-mode gratings are formed. In the absence of intermodal gratings, this set reduces to the Hopf bifurcation equations for nonlinear mode interactions. We have performed two and three transverse-mode experiments using a photorefractive ring resonator with an Fe:KNbO3 crystal. Numerically simulated coupled-mode dynamics are shown to have good correspondence with the experimental data. © 1995 The American Physical Society.