Theory of sound attenuation in amorphous solids from nonaffine motions

  title={Theory of sound attenuation in amorphous solids from nonaffine motions},
  author={Matteo Baggioli and Alessio Zaccone},
  journal={Journal of Physics: Condensed Matter},
We present a theoretical derivation of acoustic phonon damping in amorphous solids based on the nonaffine response formalism for the viscoelasticity of amorphous solids. The analytical theory takes into account the nonaffine displacements in transverse waves and is able to predict both the ubiquitous low-energy diffusive damping ∼k 2, as well as a novel contribution to the Rayleigh damping ∼k 4 at higher wavevectors and the crossover between the two regimes observed experimentally. The… 


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