Athermal Activation in Glassy Fluid

TL;DR

This paper proposes a mechanism where long-lived irradiation-induced holes in SiOx nanowires reduce energy barriers for network rearrangements, explaining their unexpectedly high fluidity under modest irradiation.

Contribution

It introduces a novel athermal activation mechanism based on hole lifetime and local configuration dynamics, linking microscopic processes to macroscopic fluidity.

Findings

Long lifetime of holes suppresses energy barriers for network moves.

Activation rate depends exponentially on the hole lifetime.

Viscosity is highly sensitive to the athermal activation mechanism.

Abstract

In this article, the mechanism of the unexpected high fluidity in SiOx nanowire under modest irradiation was proposed, the high fluidity is attributed to the long lifetime of irradiation-induced holes, which arise from formation of small polarons. The holes created in irradiation could have a long lifetime, and localized in space, such missing of bonding electron could suppress the energy barrier(athermal activation effect) for a Pachner move of the network. The atomic level dynamics of the system is proposed by interaction of phonon and local configuration, the activation effect was then studied with passing rate of corresponding stochastic dynamic equation, calculation shows an exponential dependent of the time-lapse of Pachner move to lifetime of the activation, furthermore, connection between the local configuration time and viscosity of the fluid indicates a strong sensitivity of viscosity to lifetime of the athermal activation, such mechanism would give an effective interpretation to the unexpected high fluidity together with the passivation effect of the conductor on the material.