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arXiv · 0709.3003

Coherent backscattering of ultrasound without a source

Eric Larose·Oleg I. Lobkis·Richard L. Weaver
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Abstract

Coherent backscattering is due to constructive interferences of reciprocal paths and leads to an enhancement of the intensity of a multiply scattered field near its source. To observe this enhancement an array of receivers is conventionally placed close to the source. Our approach here is different. In a first experiment, we recover the coherent backscattering effect (CBE) within an array of sources and a distant receiver using time correlation of diffuse fields. The enhancement cone has an excellent spatial resolution. The dynamics of the enhancement factor is studied in a second experiment using correlation of thermal phonons at the same ultrasonic frequencies, without any active source.

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Eric Larose, Oleg I. Lobkis, Richard L. Weaver. 2007-09-19. Coherent backscattering of ultrasound without a source. https://doi.org/10.1209/epl%2Fi2006-10277-3

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