Observation of phonon modes in a bottle microresonator
Takashi Yamamoto, Osaka University
Whispering-gallery-mode (WGM) resonators with various geometries have actively studied in the past two decades. A bottle shaped WGM resonator has been proposed in 2003 and attracted much interest because of their high optical quality factors above 108 and 3D confinement of optical modes. Recently, we have succeeded the fabrication of the bottle microresonator from an optical fiber by a heat and pull technique with a Hydrogen-Oxygen flame. With the bottle microresonators, we have observed a phonon lasing via mechanical vibration caused by the radiation pressure of the light  and an acoustic phonon via the Brillouin scattering .
 M. Asano, Y. Takeuchi, W. Chen, S. K. Ozdemir, R. Ikuta, L. Yang, N. Imoto, T. Yamamoto, "Observation of optomechanical coupling in a microbottle resonator" Laser & Photonics Reviews 10, 603 (2016).
 M. Asano, Y. Takeuchi, S. K. Ozdemir, R. Ikuta, L. Yang, N. Imoto, T. Yamamoto, "Stimulated Brillouin scattering and Brillouin-coupled four-wave-mixing in a silica microbottle resonator" Opt. Express 24, 12082 (2016).