Disentangling defects and sound modes in disordered solids. Issue 34 (3rd August 2017)

• Record Type: Journal Article
• Authors: Wijtmans, Sven; Manning, M. Lisa
• Is Part Of: Soft matter. Volume 13:Issue 34(2017)
• Page Start: 5649
• Page End: 5655
• Publication Date: 2017-08-03
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/c7sm00792b
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : Adding an artificial potential to simulations of disordered solids isolates localized excitations from phonon-like modes in the vibrational spectrum. These structural defects predict locations and displacements in particle rearrangements. Abstract : We develop a new method to isolate localized defects from extended vibrational modes in disordered solids. This method augments particle interactions with an artificial potential that acts as a high-pass filter: it preserves small-scale structures while pushing extended vibrational modes to higher frequencies. The low-frequency modes that remain are "bare" defects; they are exponentially localized without the quadrupolar tails associated with elastic interactions. We demonstrate that these localized excitations are excellent predictors of plastic rearrangements in the solid. We characterize several of the properties of these defects that appear in mesoscopic theory of plasticity, including their distribution of energy barriers, number density, and size, which is a first step in testing and revising continuum models for plasticity in disordered solids.