English

In search of multipolar order on the Penrose tiling

Materials Science 2009-11-13 v1

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.

Keywords

Cite

@article{arxiv.0805.1216,
  title  = {In search of multipolar order on the Penrose tiling},
  author = {E. Y. Vedmedenko and Shahar Even-Dar Mandel and Ron Lifshitz},
  journal= {arXiv preprint arXiv:0805.1216},
  year   = {2009}
}