Dynamical glass transition: critical temperature T_c and memory kernel in MD-simulated Ni_{0.8}Zr_{0.2}

TL;DR

This study uses molecular dynamics simulations to analyze the critical temperature for the glass transition in Ni-Zr alloys, validating mode-coupling theory predictions through multiple independent measures.

Contribution

It provides a comprehensive validation of the mode-coupling theory's critical temperature estimates using various simulation-based quantities in a Ni-Zr glass-forming system.

Findings

Critical temperature T_c estimated within 10% across methods

Nonergodicity parameters confirm the arrested state

Diffusion coefficients align with theoretical predictions

Abstract

We use molecular dynamics computer simulations to investigate a critical temperature T_c for a dynamical glass transition as proposed by the mode-coupling theory (MCT) of dense liquids in a glass forming Ni_{0.8}Zr_{0.2}-system. The critical temperature T_c are analyzed from different quantities and checked the consistency of the estimated values, i.e. from (i) the non-vanishing nonergodicity parameters as asymptotic solutions of the MCT equations in the arrested state, (ii) the ${\bf{g}}_m$-parameters describing the approach of the melt towards the arrested state on the ergodic side, (iii) the diffusion coefficients in the melt. The resulting T_c values are found to agree within about 10%.