A p-Spin Interaction Ashkin-Teller Spin-Glass Model

I. S. Queiroz Jr.; F. A. da Costa; F. D. Nobre

doi:10.1016/s0378-4371(02)00581-2

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A p-Spin Interaction Ashkin-Teller Spin-Glass Model

I. S. Queiroz Jr.·F. A. da Costa·F. D. Nobre

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Abstract

A p-spin interaction Ashkin-Teller spin glass, with three independent Gaussian probability distributions for the exchange interactions, is studied by means of the replica method. A simple phase diagram is obtained within the replica-symmetric approximation, presenting an instability of the paramagnetic solution at low temperatures. The replica-symmetry-breaking procedure is implemented and a rich phase diagram is obtained; besides the paramagnetic phase, three distinct spin-glass phases appear. Three first-order critical frontiers are found and they all meet at a triple point; among such lines, two of them present discontinuities in the order parameters, but no latent heat, whereas the other one exhibits both discontinuities in the order parameters and a finite latent heat.

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I. S. Queiroz Jr., F. A. da Costa, F. D. Nobre. 2001-11-26. A p-Spin Interaction Ashkin-Teller Spin-Glass Model. https://doi.org/10.1016/s0378-4371(02)00581-2

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