DYNAMICAL TUNNELING IN OPTICAL CAVITIES

The lifetime of whispering gallery modes in a dielectric cavity with a metallic inclusion is shown to fluctuate by orders of magnitude when size and location of the inclusion are varied. We ascribe these fluctu ations to tunneling transitions between resonances quantized in differ ent regions of phase space. This interpretation is confirmed by a comp arison of the classical phase space structure with the Husimi distribu tion of the resonant modes. A model Hamiltonian is introduced that des cribes the phenomenon and shows that it can be expected in a more gene ral class of systems.