Signatures of glass formation in a fluidized bed of hard spheres

TL;DR

This study shows that a fluidized bed of hard spheres exhibits glass-like properties during defluidization, including heterogeneity, rate dependence, and jamming, making it a useful model for studying glass formation and jamming phenomena.

Contribution

It introduces a fluidized bed of hard spheres as a new experimental system to investigate glass formation and jamming behaviors.

Findings

Final state is rate dependent.

Heterogeneity increases with time and length scales.

Jamming can be induced by small flow rate increases.

Abstract

We demonstrate that a fluidized bed of hard spheres during defluidization displays properties associated with formation of a glass. The final state is rate dependent, and as this state is approached, the bed exhibits heterogeneity with increasing time and length scales. The formation of a glass results in the loss of fluidization and an arrest of macroscopic particle motion. Microscopic motion persists in this state, but the bed can be jammed by application of a small increase in flow rate. Thus a fluidized bed can serve as a test system for studies of glass formation and jamming.