A ray-optics model is developed to describe the spoiling of the high-Q (whispering gallery) modes of ring-shaped cavities as they are deformed from perfect circularity. A sharp threshold is found for the onset of Q spoiling as predicted by the Kolmogorov-Arnol’d-Moser (KAM) theorem of nonlinear dynamics. Beyond the critical deformation bc, Q ~ (b − bc)−α,α ≈ 2.4–2.6. The escaping light emerges in certain specific directions, which may be predicted.
© 1994 Optical Society of America
Original Manuscript: June 20, 1994
Published: November 1, 1994
J. U. Nöckel, A. D. Stone, and R. K. Chang, "Q spoiling and directionality in deformed ring cavities," Opt. Lett. 19, 1693-1695 (1994)