Nonlinear effects in ultrahigh Q optical resonators

We report efficient generation of nonlinear phenomena related to third order optical non-linear susceptibility ?(3) interactions in resonant silica microspheres and microbubbles. The interactions here reported are: Third harmonic Generation (THG), Stimulated Raman Scattering (SRS), and four wave mixing processes comprising Stimulated Anti-stokes Raman Scattering (SARS) and comb generation. Unusually strong anti-Stokes components and extraordinarily symmetric spectra have been observed. Resonant SARS and SRS corresponding to different Raman bands were also observed. The lack of correlation between stimulated anti-stokes and stokes scattering spectra indicates that the signal has to be resonant with the cavity.