Cooling-rate dependence of kinetic and mechanical stability of simulated glasses

TL;DR

This paper investigates how cooling rates affect the kinetic and mechanical stability of simulated glasses, providing a basis for comparing simulated and experimental ultrastable glasses.

Contribution

It introduces a method to assess the stability of simulated glasses formed by cooling, enabling comparison with experimental ultrastable glasses.

Findings

Stability increases slowly with decreasing cooling rate.

Transformation time to liquid lengthens with lower cooling rates.

Shear modulus and inherent structure energies reflect increased stability.

Abstract

Recently, ultrastable glasses have been created through vapor deposition. Subsequently, computer simulation algorithms have been proposed that mimic the vapor deposition process and result in simulated glasses with increased stability. In addition, random pinning has been used to generate very stable glassy configurations without the need for lengthy annealing or special algorithms inspired by vapor deposition. Kinetic and mechanical stability of experimental ultrastable glasses is compared to those of experimental glasses formed by cooling. We provide the basis for a similar comparison for simulated stable glasses: we analyze the kinetic and mechanical stability of simulated glasses formed by cooling at a constant rate by examining the transformation time to a liquid upon rapid re-heating, the inherent structure energies, and the shear modulus. The kinetic and structural stability increases slowly with decreasing cooling rate. The methods outlined here can be used to assess kinetic and mechanical stability of simulated glasses generated by using specialized algorithms.