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Spin-glass behaviour on random lattices

M. O. Hase·J. R. L. de Almeida·S. R. Salinas
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Abstract

The ground-state phase diagram of an Ising spin-glass model on a random graph with an arbitrary fraction $w$ of ferromagnetic interactions is analysed in the presence of an external field. Using the replica method, and performing an analysis of stability of the replica-symmetric solution, it is shown that $w=1/2$, correponding to an unbiased spin glass, is a singular point in the phase diagram, separating a region with a spin-glass phase ($w<1/2$) from a region with spin-glass, ferromagnetic, mixed, and paramagnetic phases ($w>1/2$).

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M. O. Hase, J. R. L. de Almeida, S. R. Salinas. 2012-10-11. Spin-glass behaviour on random lattices. https://doi.org/10.1088/1742-5468%2F2012%2F10%2Fp10007

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