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arXiv · 0805.1216

In search of multipolar order on the Penrose tiling

E. Y. Vedmedenko·Shahar Even-Dar Mandel·Ron Lifshitz
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Abstract

Based on Monte Carlo calculations, multipolar ordering on the Penrose tiling, relevant for two-dimensional molecular adsorbates on quasicrystalline surfaces and for nanomagnetic arrays, has been analyzed. These initial investigations are restricted to multipolar rotors of rank one through four - described by spherical harmonics Ylm with l=1...4 and restricted to m=0 - positioned on the vertices of the rhombic Penrose tiling. At first sight, the ground states of odd-parity multipoles seem to exhibit long-range multipolar order, indicated by the appearance of a superstructure in the form of the decagonal Hexagon-Boat-Star tiling, in agreement with previous investigations of dipolar systems. Yet careful analysis establishes that long-range multipolar order is absent in all cases investigated here, and only short-range order exists. This result should be taken as a warning for any future analysis of order in either real or simulated arrangements of multipoles on quasiperiodic templates.

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E. Y. Vedmedenko, Shahar Even-Dar Mandel, Ron Lifshitz. 2008-05-08. In search of multipolar order on the Penrose tiling. https://doi.org/10.1080/14786430802302059

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