Non-Universality of the Specific Heat in Glass Forming Systems

TL;DR

This study reveals two distinct specific heat peaks in a 2D glass-forming system, challenging the notion of universality and linking peaks to micro-melting of different clusters.

Contribution

It uncovers a second specific heat peak in a classical glass-former model, providing new insights into the non-universal behavior of specific heat in glass transition.

Findings

Discovery of a second specific heat peak at lower temperatures

Explanation of peaks via micro-melting of clusters

Implication that specific heat behavior is non-universal

Abstract

We present new simulation results for the specific heat in a classical model of a binary mixture glass-former in two dimensions. We show that in addition to the formerly observed specific heat peak there is a second peak at lower temperatures which was not observable in earlier simulations. This is a surprise, as most texts on the glass transition expect a single specific heat peak. We explain the physics of the two specific heat peaks by the micro-melting of two types of clusters. While this physics is easily accessible, the consequences are that one should not expect any universality in the temperature dependence of the specific heat in glass formers.