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arXiv · 1906.07045

Phasonic Diffusion and Self-confinement of Decagonal Quasicrystals in Hyperspace

Johannes Hielscher·Miriam Martinsons·Michael Schmiedeberg·Sebastian C. Kapfer
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Abstract

We introduce a novel simulation method that is designed to explore fluctuations of the phasonic degrees of freedom in decagonal colloidal quasicrystals. Specifically, we attain and characterise thermal equilibrium of the phason ensemble via Monte Carlo simulations with particle motions restricted to elementary phasonic flips. We find that, at any temperature, the random tiling ensemble is strongly preferred over the minimum phason-strain quasicrystal. Phasonic flips are the dominant carriers of diffusive mass transport in physical space. Sub-diffusive transients suggest cooperative flip behaviour on short time scales. In complementary space, particle mobility is geometrically restricted to a thin ring around the acceptance domain, resulting in self-confinement and persistent phasonic order.

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Johannes Hielscher, Miriam Martinsons, Michael Schmiedeberg, Sebastian C. Kapfer. 2019-06-17. Phasonic Diffusion and Self-confinement of Decagonal Quasicrystals in Hyperspace. https://doi.org/10.1088/1742-6596/1458/1/012018

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