Phase diagram and critical exponents of a Potts gauge glass
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.
- Publication:
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Physical Review E
- Pub Date:
- February 2002
- DOI:
- 10.1103/PhysRevE.65.026113
- arXiv:
- arXiv:cond-mat/0105587
- Bibcode:
- 2002PhRvE..65b6113L
- Keywords:
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- Condensed Matter - Statistical Mechanics;
- Condensed Matter - Disordered Systems and Neural Networks
- E-Print:
- Latex, 7 pages, 3 figures, v2: 1 reference added