Elastic constant dishomogeneity and $Q^2$ dependence of the broadening of the dynamical structure factor in disordered systems
Disordered Systems and Neural Networks
2009-10-31 v1
Abstract
We propose an explanation for the quadratic dependence on the momentum , of the broadening of the acoustic excitation peak recently found in the study of the dynamic structure factor of many real and simulated glasses. We ascribe the observed law to the spatial fluctuations of the local wavelength of the collective vibrational modes, in turn produced by the dishomegeneity of the inter-particle elastic constants. This explanation is analitically shown to hold for 1-dimensional disordered chains and satisfatorily numerically tested in both 1 and 3 dimensions.
Keywords
Cite
@article{arxiv.cond-mat/9809308,
title = {Elastic constant dishomogeneity and $Q^2$ dependence of the broadening of the dynamical structure factor in disordered systems},
author = {M. Montagna and G. Ruocco and G. Viliani and R. Di Leonardo and R. Dusi and G. Monaco and M. Sampoli and T. Scopigno},
journal= {arXiv preprint arXiv:cond-mat/9809308},
year = {2009}
}
Comments
4 pages, RevTeX, 5 postscript figures