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Temperature-dependent "phason" elasticity in a random tiling quasicrystal

M. Mihalkovic·C. L. Henley
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Abstract

Both ``phason'' elastic constants have been measured from Monte Carlo simulations of a random-tiling icosahedral quasicrystal model with a Hamiltonian. The low-temperature limit approximates the ``canonical-cell'' tiling used to describe several real quasicrystals. The elastic constant K2 changes sign from positive to negative with decreasing temperature; in the ``canonical-cell'' limit, K2/K1 appears to approach -0.7, about the critical value for a phason-mode modulation instability. We compare to the experiments on i-AlPdMn and i-AlCuFe.

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M. Mihalkovic, C. L. Henley. 2002-05-13. Temperature-dependent "phason" elasticity in a random tiling quasicrystal. https://doi.org/10.1103/physrevb.70.092202

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