title: Imaging of transient surface acoustic waves by full-field photorefractive interferometry.
abstract: A stroboscopic full-field imaging technique based on photorefractive interferometry for the visualization of rapidly changing surface displacement fields by using of a standard charge-coupled device (CCD) camera is presented. The photorefractive buildup of the space charge field during and after probe laser pulses is simulated numerically. The resulting anisotropic diffraction upon the refractive index grating and the interference between the polarization-rotated diffracted reference beam and the transmitted signal beam are modeled theoretically. The method is experimentally demonstrated by full-field imaging of the propagation of photoacoustically generated surface acoustic waves with a temporal resolution of nanoseconds. The surface acoustic wave propagation in a 23 mm × 17 mm area on an aluminum plate was visualized with 520 × 696 pixels of the CCD sensor, yielding a spatial resolution of 33 μm. The short pulse duration (8 ns) of the probe laser yields the capability of imaging SAWs with frequencies up to 60 MHz.
authors.affiliation: Key Laboratory of Modern Acoustics, Nanjing University, Nanjing 210093, China.
authors.forename: Jichuan
authors.initials: J
authors.lastname: Xiong
authors.affiliation: Key Laboratory of Modern Acoustics, Nanjing University, Nanjing 210093, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Xu
authors.affiliation: Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium.
authors.forename: Christ
authors.initials: C
authors.lastname: Glorieux
authors.affiliation: Division of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Matsuda
authors.affiliation: Key Laboratory of Modern Acoustics, Nanjing University, Nanjing 210093, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Cheng