title: Shear-induced breaking of cages in colloidal glasses: Scattering experiments and mode coupling theory.
abstract: We employ x-ray scattering on sheared colloidal suspensions and mode coupling theory to study structure factor distortions of glass-forming systems under shear. We find a transition from quadrupolar elastic distortion at small strains to quadrupolar and hexadecupolar modes in the stationary state. The latter are interpreted as signatures of plastic rearrangements in homogeneous, thermalized systems. From their transient evolution with strain, we identify characteristic strain and length-scale values where these plastic rearrangements dominate. This characteristic strain coincides with the maximum of the shear stress versus strain curve, indicating the proliferation of plastic flow. The hexadecupolar modes dominate at the wavevector of the principal peak of the equilibrium structure factor that is related to the cage-effect in mode coupling theory. We hence identify the structural signature of plastic flow of glasses.
authors.affiliation: Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Amann
authors.affiliation: Van der Waals-Zeeman Institute, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Dmitry
authors.initials: D
authors.lastname: Denisov
authors.affiliation: Van der Waals-Zeeman Institute, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Minh Triet
authors.initials: MT
authors.lastname: Dang
authors.affiliation: Deutsches Elektronen-Synchrotron, Hamburg, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Struth
authors.affiliation: Van der Waals-Zeeman Institute, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Peter
authors.initials: P
authors.lastname: Schall
authors.affiliation: Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Fuchs