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arXiv · 0907.3812

Partial order in a frustrated Potts model

Ryo Igarashi·Masao Ogata
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Abstract

We investigate a 4-state ferromagnetic Potts model with a special type of geometrical frustration on a three dimensional diamond lattice by means of Wang-Landau Monte Carlo simulation motivated by a peculiar structural phase transition found in $\beta$-pyrochlore oxide KOs$_2$O$_6$. We find that this model undergoes unconventional first-order phase transition; half of the spins in the system order in a two dimensional hexagonal-sheet-like structure, while the remaining half stay disordered. The ordered sheets and the disordered sheets stack one after another. We obtain a fairly large residual entropy at $T = 0$ which originates from the disordered sheets.

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Ryo Igarashi, Masao Ogata. 2009-07-22. Partial order in a frustrated Potts model. https://doi.org/10.1088/1742-6596/200/2/022019

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