Elastic moduli of a Brownian colloidal glass former. (11th December 2017)

• Record Type: Journal Article
• Authors: Fritschi, S; Fuchs, M
• Is Part Of: Journal of physics. Volume 30:Number 2(2018)
• Publication Date: 2017-12-11
• Subjects: shear modulus -- glass transition -- Brownian dynamics simulation -- rheology -- colloidal dispersion -- dispersion relation; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa9de4
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: The static, dynamic and flow-dependent shear moduli of a binary mixture of Brownian hard disks are studied by an event-driven molecular dynamics simulation. Thereby, the emergence of rigidity close to the glass transition encoded in the static shear modulus G ∞ is accessed by three methods. Results from shear stress auto-correlation functions, elastic dispersion relations, and the elastic response to strain deformations upon the start-up of shear flow are compared. This enables one to sample the time-dependent shear modulus G ( t ) consistently over several decades in time. By that a very precise specification of the glass transition point and of G ∞ is feasible. Predictions by mode coupling theory of a finite shear modulus at the glass transition, of α -scaling in fluid states close to the transition, and of shear induced decay in yielding glass states are tested and broadly verified.