We report experimental observations of the mode dynamics in a weakly multimode photorefractive ring oscillator with induced astigmatism. First a gallery of transverse, higher-order Gaussian modes in the system is presented. Subsequently the dynamics of beating modes and the interactions between modes belonging to different bases are examined. The latter show the transition of modes between the three equivalent mode families experimentally. Finally regions of cavity symmetry leading to different spatial modes and mode dynamics are identified.
© 2001 Optical Society of America
(030.4070) Coherence and statistical optics : Modes
(140.4780) Lasers and laser optics : Optical resonators
(190.4420) Nonlinear optics : Nonlinear optics, transverse effects in
(190.5330) Nonlinear optics : Photorefractive optics
S. Juul Jensen, R. Nicolaus, and C. Denz, "Spatial-mode dynamics in a photorefractive ring oscillator with induced astigmatism," J. Opt. Soc. Am. B 18, 966-973 (2001)