Dynamic Gardner crossover in a simple structural glass

TL;DR

This study investigates the nonequilibrium dynamics of hard disks near the jamming transition, revealing a universal dynamic Gardner crossover that is independent of preparation history and associated with complex landscape exploration.

Contribution

It introduces a generic dynamic Gardner crossover in nonequilibrium conditions, expanding understanding of jamming physics beyond equilibrium and history dependence.

Findings

Identification of a universal dynamic Gardner crossover

Decoupling Gardner signatures from aging relaxation dynamics

Observation of complex landscape exploration near jamming

Abstract

The criticality of the jamming transition responsible for amorphous solidification has been theoretically linked to the marginal stability of a thermodynamic Gardner phase. While the critical exponents of jamming appear independent of the preparation history, the pertinence of Gardner physics far from equilibrium is an open question. To fill this gap, we numerically study the nonequilibrium dynamics of hard disks compressed towards the jamming transition using a broad variety of protocols. We show that dynamic signatures of Gardner physics can be disentangled from the aging relaxation dynamics. We thus define a generic dynamic Gardner crossover regardless of the history. Our results show that the jamming transition is always accessed by exploring increasingly complex landscape, resulting in the anomalous microscopic relaxation dynamics that remains to be understood theoretically.