Well defined transition to gel-like aggregates of attractive athermal particles

TL;DR

This paper investigates the transition to gel-like aggregates in attractive athermal particles, revealing a sharp low-density tensile solid transition influenced by attraction range, with implications for understanding jamming and solidity.

Contribution

It introduces a simulation of attractive athermal particles to explore a new jamming transition, highlighting the role of attraction range and coordination in solidity.

Findings

Transition to tensile solid at low density

Critical density depends on attraction range

Solidity linked to coordination number via Maxwell counting

Abstract

In an attempt to extend the range of model jamming transitions, we simulate systems of athermal particles which attract when slightly overlapping. Following from recent work on purely repulsive systems, dynamics are neglected and relaxation performed via a potential energy minimisation algorithm. Our central finding is of a transition to a low-density tensile solid which is sharp in the limit of infinite system size. The critical density depends on the range of the attractive regime in the pair-potential. Furthermore, solidity is shown to be related to the coordination number of the packing according to the approximate constraint-counting scheme known as Maxwell counting, although more corrections need to be considered than with the repulsive-only case, as explained. We finish by discussing how the numerical difficulties encountered in this work could be overcome in future studies.