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Phase diagram of a random-anisotropy mixed-spin Ising model

A. P. Vieira·J. X. de Carvalho·S. R. Salinas
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Abstract

We investigate the phase diagram of a mixed spin-1/2--spin-1 Ising system in the presence of quenched disordered anisotropy. We carry out a mean-field and a standard self-consistent Bethe--Peierls calculation. Depending on the amount of disorder, there appear novel transition lines and multicritical points. Also, we report some connections with a percolation problem and an exact result in one dimension.

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A. P. Vieira, J. X. de Carvalho, S. R. Salinas. 2001-02-19. Phase diagram of a random-anisotropy mixed-spin Ising model. https://doi.org/10.1103/physrevb.63.184415

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