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Low-frequency Raman scattering in model disordered solids: percolators above threshold

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 Added by Gabriele Viliani
 Publication date 1997
  fields Physics
and research's language is English
 Authors O. Pilla




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The Raman coupling coefficients of site- and bond-percolators at concentration higher than percolation threshold are computed for two scattering mechanisms: Bond Polarizability (BPOL) and Dipole-Induced-Dipole (DID). The results show that DID does not follow a scaling law at low frequency, while in the case of BPOL the situation is less clear. The numerically computed frequency dependence in the case of BPOL, which can be considered a good scattering mechanism for a wide class of real glasses, is in semiquantitative agreement with experimental results.



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