Evidence for a disordered critical point in a glass-forming liquid

TL;DR

This study uses computer simulations to identify a disordered critical point in a glass-forming liquid, revealing large fluctuations in overlap that suggest a phase transition related to amorphous states.

Contribution

It provides evidence for a disordered critical point in glass-forming liquids, linking fluctuation behavior to theoretical predictions and interfacial tension between amorphous states.

Findings

Large overlap fluctuations increase as temperature decreases.

Behavior consistent with a random critical point predicted by effective field theories.

Identification of interfacial tension between amorphous metastable states.

Abstract

Using computer simulations of an atomistic glass-forming liquid, we investigate the fluctuations of the overlap between a fluid configuration and a quenched reference system. We find that large fluctuations of the overlap develop as temperature decreases, consistent with the existence of the random critical point that is predicted by effective field theories. We discuss the scaling of fluctuations near the presumed critical point, comparing the observed behaviour with that of the random-field Ising model. We argue that this critical point directly reveals the existence of an interfacial tension between amorphous metastable states, a quantity relevant both for equilibrium relaxation and for nonequilibrium melting of stable glass configurations.