2024-03-28T20:56:56Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/430622022-11-17T02:08:08Zhdl_2115_20045hdl_2115_139Acoustic whispering-gallery modes generated and dynamically imaged with ultrashort optical pulsesTachizaki, Takehiro1000030239024Matsuda, OsamuMaznev, Alex A.Wright, Oliver B.open access©2010 The American Physical Society425Broadband coherent surface phonon wave packets up to 1 GHz in a microscopic embedded disk are excited and dynamically imaged with ultrashort optical pulses. We isolate a whispering-gallery-like mode using a technique involving quadrature detection of the out-of-plane surface motion on modulating the optical excitation beam. The eigenmode distribution is obtained from spatiotemporal Fourier transforms and a radial-azimuthal decomposition demonstrates the selective excitation of a mode with 26-fold rotational symmetry and allows an estimate of the cavity Q factor to be made.American Physical Society2010-04-15engjournal articleVoRhttp://hdl.handle.net/2115/43062https://doi.org/10.1103/PhysRevB.81.1654341098-0121Physical Review B8116165434https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/43062/1/PRB81-16_165434.pdfapplication/pdf379.66 KB2010-04-15