Diffusion-Coefficient Power Laws and Defect-Driven Glassy Dynamics in Swap Acceleration

2021/11/30 by Gautham Gopinath, Chun-Shing Lee, Xin-Yuan Gao +5 · 1 voice
Materials Science · Mathematics · Physics and Astronomy · #Chemical physics #Classical mechanics #Condensed matter physics #Diffusion #Glass properties and applications #Kinetic energy #Material Dynamics and Properties #Materials science #Mathematics #Physics #Power law #Statistical physics #Statistics #Swap (finance) #Theoretical and Computational Physics #Thermodynamics

paper · doi:10.1103/physrevlett.129.168002

openalex publication_date 2022/10/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Particle swaps can drastically accelerate dynamics in glass. The mechanism is expected to be vital for a fundamental understanding of glassy dynamics. To extract defining features, we propose a partial swap model with a fraction ϕ_s of swap-initiating particles, which can only swap locally with each other or with regular particles. We focus on the swap-dominating regime. At all temperatures studied, particle diffusion coefficients scale with ϕ_s in unexpected power laws with temperature-dependent exponents, consistent with the kinetic picture of glassy dynamics. At small ϕ_s, swap initiators, becoming defect particles, induce remarkably typical glassy dynamics of regular particles. This supports defect models of glass.

Citations

• LAMMPS - a flexible simulation tool for particle-based materials modeling at the atomic, meso, and continuum scales
• Glasses and aging: A Statistical Mechanics Perspective
• Fast Monte Carlo algorithm for supercooled soft spheres
• Phase Diagram of a Polydisperse Soft-Spheres Model for Liquids and Colloids
• Does a Growing Static Length Scale Control the Glass Transition?

Discussions

• Gautham's research is centered around the physics of motion in biological systems, particularly in cell packing and cell aggregates. Check out his undergraduate work on modeling the glass transition p [bsky, 0 points, 0 comments]

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