Phase diagram and critical exponents of a Potts gauge glass

Jesper Lykke Jacobsen; Marco Picco

doi:10.1103/physreve.65.026113

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Phase diagram and critical exponents of a Potts gauge glass

Jesper Lykke Jacobsen·Marco Picco

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Abstract

The two-dimensional q-state Potts model is subjected to a Z_q symmetric disorder that allows for the existence of a Nishimori line. At q=2, this model coincides with the +/- J random-bond Ising model. For q>2, apart from the usual pure and zero-temperature fixed points, the ferro/paramagnetic phase boundary is controlled by two critical fixed points: a weak disorder point, whose universality class is that of the ferromagnetic bond-disordered Potts model, and a strong disorder point which generalizes the usual Nishimori point. We numerically study the case q=3, tracing out the phase diagram and precisely determining the critical exponents. The universality class of the Nishimori point is inconsistent with percolation on Potts clusters.

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Jesper Lykke Jacobsen, Marco Picco. 2001-06-13. Phase diagram and critical exponents of a Potts gauge glass. https://doi.org/10.1103/physreve.65.026113

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