Geometric origin of excess low-frequency vibrational modes in amorphous solids
Soft Condensed Matter
2009-11-10 v3 Disordered Systems and Neural Networks
Abstract
Glasses have a large excess of low-frequency vibrational modes in comparison with crystalline solids. We show that such a feature is a necessary consequence of the geometry generic to weakly connected solids. In particular, we analyze the density of states of a recently simulated system, comprised of weakly compressed spheres at zero temperature. We account for the observed a) constancy of the density of modes with frequency, b) appearance of a low-frequency cutoff, and c) power-law increase of this cutoff with compression. We predict a length scale below which vibrations are very different from those of a continuous elastic body.
Cite
@article{arxiv.cond-mat/0409687,
title = {Geometric origin of excess low-frequency vibrational modes in amorphous solids},
author = {Matthieu Wyart and Sidney R. Nagel and T. A. Witten},
journal= {arXiv preprint arXiv:cond-mat/0409687},
year = {2009}
}
Comments
4 pages, 2 figures. Argument rewritten, identical results