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Ising Dipoles on the Triangular Lattice

Ulrich K. Roessler
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Abstract

A cluster Monte Carlo method for systems of classical spins with purely dipolar couplings is presented. It is tested and applied for finite arrays of perpendicular Ising dipoles on the triangular lattice. This model is a modification with long-range interactions of the geometrically frustrated Ising antiferromagnet. From measurements of integrated autocorrelation times for energy, magnetization and staggered magnetizations, a high efficiency of the cluster Monte Carlo (MC) algorithm compared to a single-spin-flip algorithm is found. For the investigated model, a finite temperature transition is found which is characterized by a peak in the specific heat and in the staggered susceptibilities.

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Ulrich K. Roessler. 2001-01-26. Ising Dipoles on the Triangular Lattice. https://doi.org/10.1063/1.1358336

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