Phase transition for quenched coupled replicas in a plaquette spin model of glasses

TL;DR

This paper investigates a three-dimensional plaquette spin model exhibiting glassy dynamics, revealing a phase transition induced by coupling to a quenched configuration, with critical behavior akin to the random-field Ising model.

Contribution

It demonstrates a finite-coupling phase transition in a glassy spin model and analyzes its critical properties and interfacial free energy, connecting to theories of the glass transition.

Findings

Identification of a phase transition between low and high overlap states.

Critical points exhibit properties consistent with random-field Ising universality.

Finite-size scaling analysis of interfacial free energy costs.

Abstract

We study a three-dimensional plaquette spin model whose low temperature dynamics is glassy, due to localised defects and effective kinetic constraints. While the thermodynamics of this system is smooth at all temperatures, we show that coupling it to a second system with a fixed (quenched) configuration can lead to a phase transition, at finite coupling. The order parameter is the overlap between the copies, and the transition is between phases of low and high overlap. We find critical points whose properties are consistent with random-field Ising universality. We analyse the interfacial free energy cost between the high- and low-overlap states that coexist at (and below) the critical point, and we use this cost as the basis for a finite-size scaling analysis. We discuss these results in the context of mean-field and dynamical facilitation theories of the glass transition.