Acoustic Rayleigh Wave Turbulence in Soft Viscoelastic Matter.

Evidence of discrete acoustic Rayleigh wave turbulence (DARWT) is reported on the free surface of complex viscoelastic materials under monochromatic excitation. These surface elastic non-linear Rayleigh waves exhibit dispersionless dynamics governed by bulk shear rigidity at coexistence with dispersive capillary waves supported by surface tension. Using Laser Doppler Vibrometry (LDV), the discrete Kolmogorov-Zakharov (KZ) spectrum is measured, characterized by a power-law envelope in an inertial cascade of discrete harmonics.