Lombard O, Barrière C, Leroy V
Laboratoire Matière et Systèmes Complexes, Universitè Paris-Diderot, CNRS (UMR 7057), Paris, France.
Institut Langevin, ESPCI ParisTech, CNRS (UMR 7587), PSL Research University, Paris, France.
Ultrasonics. 2017 Jul;78:110-114. doi: 10.1016/j.ultras.2017.03.008. Epub 2017 Mar 15.
A single layer of gas bubbles in a yield-stress fluid is experimentally shown to behave as a phase-conjugated (PC) mirror with a thickness 250 times smaller than the wavelength (0.14mm-diameter bubbles for phase-conjugation at 40kHz). A high amplitude pump wave at frequency 80kHz interacts with a lower amplitude probe wave centered at 40kHz. A PC-reflection coefficient of 0.15 is obtained for a 50kPa pump. A perturbative second-order theory is shown to quantitatively describe the experimental observations.
