Low-frequency behavior of beads constrained on a lattice.

  title={Low-frequency behavior of beads constrained on a lattice.},
  author={Bruno Gilles and Christophe F D Coste},
  journal={Physical review letters},
  volume={90 17},
We study sound propagation in a triangular lattice of spherical beads under isotropic stress. Polydispersity of real beads breaks some contacts, creating a disordered lattice of contacting beads. At large stress, the sound velocity behaves according to Hertz contact law and departs from it at lower stress. This evolution is reversible, with the same crossover when increasing or decreasing the stress, for a given piling. Correlations are much more sensitive to disorder. When calculated with… CONTINUE READING