Dynamics of particle flips in two-dimensional quasicrystals

TL;DR

This study uses molecular dynamics simulations to analyze particle flip dynamics in two-dimensional quasicrystals, revealing stochastic motion, reordering mechanisms, and diffusion behavior influenced by temperature.

Contribution

It provides detailed insights into the microscopic flip mechanisms and their role in quasicrystal dynamics, which were previously less understood.

Findings

Particle flips include single-particle jumps and multi-particle ring moves.

Flip mechanisms facilitate long-term reordering and diffusion.

Diffusion follows an Arrhenius temperature dependence.

Abstract

The dynamics of quasicrystals is more complicated than the dynamics of periodic solids and difficult to study in experiments. Here, we investigate a decagonal and a dodecagonal quasicrystal using molecular dynamics simulations of the Lennard-Jones-Gauss interaction system. We observe that the short time dynamics is dominated by stochastic particle motion, so-called phason flips, which can be either single-particle jumps or correlated ring-like multi-particle moves. Over long times, the flip mechanism is efficient in reordering the quasicrystals and can generate diffusion. The temperature dependence of diffusion is described by an Arrhenius law. We also study the spatial distribution and correlation of mobile particles by analyzing the dynamic propensity.