Optomechanics in anisotropic liquid crystal -filled micro-bubble resonators

In this paper, we report on the realization of optomechanics and its broad tuning in liquid crystal-filled micro-bubble resonators (LC-MBR). Acoustic anisotropy of LC has enriched optomechanical resonant modes in such whispering-gallery modes (WGM) cavities. Meanwhile anisotropic dependence of sound speed of LC on temperature strongly enhances the tuning ability of the resonances. By applying magnetic field to control re-orientation of LC in MBR, optomechanical resonant frequency changes significantly after magnetic field goes beyond Fréedericksz transition threshold. By designing such an optomachanical system, optomechanical oscillator with broad tuning range can be realized.