Watching Ripples on Crystals
نویسندگان
چکیده
منابع مشابه
Watching surface waves in phononic crystals.
In this paper, we review results obtained by ultrafast imaging of gigahertz surface acoustic waves in surface phononic crystals with one- and two-dimensional periodicities. By use of quasi-point-source optical excitation, we show how, from a series of images that form a movie of the travelling waves, the dispersion relation of the acoustic modes, their corresponding mode patterns and the positi...
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Broadband surface phonon wave packets on a phononic crystal made up of a microstructured line pattern are tracked in two dimensions and in real time with an ultrafast optical technique. The eigenmode distribution and the 2D acoustic band structure are obtained from spatiotemporal Fourier transforms of the data up to 1 GHz. We find stop bands at the zone boundaries for both leaky-longitudinal an...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2002
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.88.185504