Jamming transition and inherent structures of hard spheres and disks

Abstract

Recent studies show that volume fractions φ J at the jamming transition of frictionless hard spheres and disks are not uniquely determined but exist over a continuous range. Motivated by this observation, we numerically investigate the dependence of φ J on the initial configurations of the parent fluid equilibrated at a volume fraction φ eq, before compressing to generate a jammed packing. We find that φ J remains constant when φ eq is small but sharply increases as φ eq exceeds the dynamic transition point which the mode-coupling theory predicts. We carefully analyze configurational properties of both jammed packings and parent fluids and find that, while all jammed packings remain isostatic, the increase of φ J is accompanied with subtle but distinct changes of local orders, a static length scale, and an exponent of the finite-size scaling. These results are consistent with the scenario of the random first-order transition theory of the glass transition. © 2012 American Physical Society.