# Driven activation versus thermal activation

## TL;DR

This study investigates how external shear influences activated dynamics in glassy systems, introducing a concept of driven activation characterized by an effective temperature linked to fluctuation-dissipation relations.

## Contribution

It demonstrates that external driving significantly affects barrier crossing rates and introduces a novel effective temperature concept for nonequilibrium systems.

## Key findings

- External driving alters barrier crossing rates
- Effective temperature aligns with fluctuation-dissipation measurements
- Analytical model supports simulation results

## Abstract

Activated dynamics in a glassy system undergoing steady shear deformation is studied by numerical simulations. Our results show that the external driving force has a strong influence on the barrier crossing rate, even though the reaction coordinate is only weakly coupled to the nonequilibrium system. This "driven activation" can be quantified by introducing in the Arrhenius expression an effective temperature, which is close to the one determined from the fluctuation-dissipation relation. This conclusion is supported by analytical results for a simplified model system.