Quasicrystalline Order in Binary Dipolar Systems

TL;DR

This study explores the emergence of quasicrystalline order in two-dimensional binary dipolar systems, revealing that such configurations can be energetically favorable and robust locally, despite not being thermodynamically stable.

Contribution

It demonstrates the potential for quasicrystalline arrangements in dipolar systems without intrinsic length scales, using energy minimization and simulation methods.

Findings

Quasicrystalline configurations are local energy minima.

These configurations are not thermodynamically stable.

Local quasicrystalline order can be strong in disordered states.

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.