Shearing small glass-forming systems: a potential energy landscape perspective

Abstract

Understanding the yielding of glass-forming systems upon shearing is notoriously difficult since it is a strong non-equilibrium effect. Here we show that the concept of the potential energy landscape (PEL), developed for the quiescent state, can be extended to shearing. When introducing an appropriate coarse graining of the extended PEL for sheared systems, one can distinguish two fundamentally different types of plastic events, namely inherent structures (IS) vs. minimized structure (MS) transitions. We apply these concepts to non-cyclic and cyclic shearing of small systems, which allow us to characterize the properties of elementary plastic events. Whereas the general properties of the stress-strain curves are similar to larger systems, a closer analysis reveals significantly different properties. This allows one to identify the impact of the elastic coupling in larger systems. The concept of MS enables us to relate the stress overshoot of a single trajectory to the emergence of an MS transition. Furthermore, the occurrence of limit cycles can be characterized in great detail for the small systems and connections to the properties of the PEL can be formulated. Possible implications of our small-system results for the macroscopic limit are discussed.

References in corpus (4)

• A microscopic view of the yielding transition in concentrated emulsions
• Start-up Shear of Concentrated Colloidal Hard Spheres: Stresses, Dynamics and Structure
• Collective nonaffine displacements in amorphous materials during large-amplitude oscillatory shear
• Heterogeneous dynamics during yielding of glasses: effect of aging

Cited by in corpus (6)

• The potential energy states and mechanical properties of thermally cycled binary glasses
• Accessing a broader range of energy states in metallic glasses by variable-amplitude oscillatory shear
• Contact network changes in ordered and disordered disk packings
• Manipulating the Glass Transition in Nanoscale
• The thermal jamming transition of soft harmonic disks in two dimensions
• Energy landscape description of the clustering transition for active soft spheres