Pinning effects in a two-dimensional cluster glass

We study numerically the nonequilibrium glass formation and depinning transition of a system of two-dimensional cluster-forming monodisperse particles in the presence of pinning disorder. The pairwise interaction potential is nonmonotonic and is motivated by the intervortex forces in type-1.5 superconductors but also applies to a variety of other systems. Such systems can form cluster glasses due to the intervortex interactions following a thermal quench, without underlying disorder. We study the effects of vortex pinning in these systems. We find that a small density of pinning centers of moderate depth has a limited effect on vortex glass formation, i.e., formation of vortex glasses is dominated by intervortex interactions. At higher densities, pinning can significantly affect glass formation. The cluster glass depinning, under a constant driving force, is found to be plastic, with features distinct from non-cluster-forming systems such as clusters merging and breaking. We find that, in general, vortices with cluster-forming interaction forces can exhibit stronger pinning effects than regular vortices.

Automated summary

This study numerically investigates nonequilibrium glass formation and depinning transition in a system of two-dimensional cluster-forming monodisperse particles with pinning disorder. The results show that vortex interaction is the dominant factor in cluster glass formation, while pinning can significantly affect glass formation. Vortices with cluster-forming interaction forces exhibit stronger pinning effects compared to regular vortices.