title: Coherent transmission of an ultrasonic shock wave through a multiple scattering medium.
abstract: We report measurements of the transmitted coherent (ensemble-averaged) wave resulting from the interaction of an ultrasonic shock wave with a two-dimensional random medium. Despite multiple scattering, the coherent waveform clearly shows the steepening that is typical of nonlinear harmonic generation. This is taken advantage of to measure the elastic mean free path and group velocity over a broad frequency range (2-15 MHz) in only one experiment. Experimental results are found to be in good agreement with a linear theoretical model taking into account spatial correlations between scatterers. These results show that nonlinearity and multiple scattering are both present, yet uncoupled.
authors.affiliation: Institut Langevin-Ondes et Images, Université Denis Diderot Paris VII, ESPCI ParisTech, CNRS (UMR 7587), 1 rue Jussieu, 75005 Paris, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Viard
authors.forename: Bruno
authors.initials: B
authors.lastname: Giammarinaro
authors.forename: Arnaud
authors.initials: A
authors.lastname: Derode
authors.forename: Christophe
authors.initials: C
authors.lastname: Barrière