Experimental evidence for localization of acoustic waves in three dimensions

Abstract
We present experimental evidence for localization of acoustic waves in a novel three-dimensional system. The system consists of a polymer melt solidifying by the growth of spherical semicrystalline nuclei. For sufficiently high excitation frequencies, we find renormalization of sound speed and intense absorption peaks over very narrow ranges of wave number. We generalize theory to include shear modes in the scatterers, and find that localization is consistent with our observations.