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arXiv · 1006.1836

Dynamics of particle flips in two-dimensional quasicrystals

Michael Engel·Masahiro Umezaki·Hans-Rainer Trebin·Takashi Odagaki
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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.

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Michael Engel, Masahiro Umezaki, Hans-Rainer Trebin, Takashi Odagaki. 2010-06-09. Dynamics of particle flips in two-dimensional quasicrystals. https://doi.org/10.1103/physrevb.82.134206

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