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Absence of Dipole Glass Transition for Randomly Dilute Classical Ising Dipoles

Joseph Snider·Clare C. Yu
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Abstract

Dilute dipolar systems in three dimensions are expected to undergo a spin glass transition as the temperature decreases. Contrary to this, we find from Wang-Landau Monte Carlo simulations that at low concentrations $x$, dipoles randomly placed on a cubic lattice with dipolar interactions do not undergo a phase transition. We find that in the thermodynamic limit the ``glass'' transition temperature $T_g$ goes to zero as $1/\sqrt{N}$ where $N$ is the number of dipoles. The entropy per particle at low temperatures is larger for lower concentrations ($x=4.5%$) than for higher concentrations ($x=20%$).

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Joseph Snider, Clare C. Yu. 2005-08-23. Absence of Dipole Glass Transition for Randomly Dilute Classical Ising Dipoles. https://doi.org/10.1103/physrevb.72.214203

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