Steady-state, effective-temperature dynamics in a glassy material

TL;DR

This paper analyzes numerical simulations of a glassy material using STZ theory, confirming the importance of effective temperature as a state variable and revealing a glass transition driven by shear rate.

Contribution

It validates the STZ theory against simulation data and uncovers a shear-rate-induced glass transition characterized by super-Arrhenius behavior.

Findings

Effective temperature acts as a key dynamical variable.

The system exhibits a classic glass transition under shear.

Super-Arrhenius behavior observed in the effective temperature.

Abstract

We present an STZ-based analysis of numerical simulations by Haxton and Liu (HL). The extensive HL data sharply test the basic assumptions of the STZ theory, especially the central role played by the effective disorder temperature as a dynamical state variable. We find that the theory survives these tests, and that the HL data provide important and interesting constraints on some of its specific ingredients. Our most surprising conclusion is that, when driven at various constant shear rates in the low-temperature glassy state, the HL system exhibits a classic glass transition, including super-Arrhenius behavior, as a function of the effective temperature.