%0 Journal Article
%A Martín Mayor, Víctor
%A Parisi, G.
%A Verrocchio, P.
%T Dynamical structure factor in disordered systems
%D 2000
%@ 1063-651X
%U https://hdl.handle.net/20.500.14352/60329
%X We study the spectral width as a function of the external momentum for the dynamical structure factor of a disordered harmonic solid, considered as a toy model for supercooled liquids and glasses. In the contexts of both the single-link coherent potential approximation and a single-defect approximation, two different regimes are clearly identified: if the density of states at zero energy is zero, the usual p^(4) law is recovered for small momentum. On the contrary, if the disorder induces a nonvanishing density of states at zero energy, a linear behavior is obtained. The dynamical structure factor is numerically calculated in lattices as large as 96^(3) and satisfactorily agrees with the analytical computations.
%~