open access

https://hdl.handle.net/2115/71590

Active chiral control of GHz acoustic whispering-gallery modes

英語

2017-10-02

American Institute of Physics (AIP)

Applied physics letters

111(14)

144103

We selectively generate chiral surface-acoustic whispering-gallery modes in the gigahertz range on a microscopic disk by means of an ultrafast time-domain technique incorporating a spatial light modulator. Active chiral control is achieved by making use of an optical pump spatial profile in the form of a semicircular arc, positioned on the sample to break the symmetry of clockwise-and counterclockwise-propagating modes. Spatiotemporal Fourier transforms of the interferometrically monitored two-dimensional acoustic fields measured to micron resolution allow individual chiral modes and their azimuthal mode order, both positive and negative, to be distinguished. In particular, for modes with 15-fold rotational symmetry, we demonstrate ultrafast chiral control of surface acoustic waves in a micro-acoustic system with picosecond temporal resolution. Applications include nondestructive testing and surface acoustic wave devices.

学術雑誌論文

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This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing.The following article appeared in http://aip.scitation.org/journal/apl and may be found at http://aip.scitation.org/doi/10.1063/1.4994886.

0003-6951