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arXiv · 1507.05784

Macroscopic Degeneracy and order in the 3d plaquette Ising model

Desmond A. Johnston·Marco Mueller·Wolfhard Janke
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Abstract

The purely plaquette 3d Ising Hamiltonian with the spins living at the vertices of a cubic lattice displays several interesting features. The symmetries of the model lead to a macroscopic degeneracy of the low-temperature phase and prevent the definition of a standard magnetic order parameter. Consideration of the strongly anisotropic limit of the model suggests that a layered, "fuki-nuke" order still exists and we confirm this with multicanonical simulations. The macroscopic degeneracy of the low-temperature phase also changes the finite-size scaling corrections at the first-order transition in the model and we see this must be taken into account when analysing our measurements.

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Desmond A. Johnston, Marco Mueller, Wolfhard Janke. 2015-07-21. Macroscopic Degeneracy and order in the 3d plaquette Ising model. https://doi.org/10.1142/s0217984915501092

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