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Quasicrystalline Order in Binary Dipolar Systems

Falk Scheffler·Philipp Maass·Johannes Roth·Holger Stark
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Abstract

Motivated by recent experimental findings, we investigate the possible occurrence and characteristics of quasicrystalline order in two-dimensional mixtures of point dipoles with two sorts of dipole moments. Despite the fact that the dipolar interaction potential does not exhibit an intrinsic length scale and cannot be tuned a priori to support the formation of quasicrystalline order, we find that configurations with long--range quasicrystallinity yield minima in the potential energy surface of the many particle system. These configurations emanate from an ideal or perturbed ideal decoration of a binary tiling by steepest descent relaxation. Ground state energy calculations of alternative ordered states and parallel tempering Monte-Carlo simulations reveal that the quasicrystalline configurations do not correspond to a thermodynamically stable state. On the other hand, steepest descent relaxations and conventional Monte-Carlo simulations suggest that they are rather robust against fluctuations. Local quasicrystalline order in the disordered equilibrium states can be strong.

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Falk Scheffler, Philipp Maass, Johannes Roth, Holger Stark. 2004-04-19. Quasicrystalline Order in Binary Dipolar Systems. https://doi.org/10.1140/epjb%2Fe2004-00359-6

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