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arXiv · 1410.8397

Critical aspects of three-dimensional anisotropic spin-glass models

T. Papakonstantinou·N. G. Fytas·A. Malakis·I. Lelidis
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Abstract

We study the $\pm J$ three-dimensional Ising model with a longitudinal anisotropic bond randomness on the simple cubic lattice. The random exchange interaction is applied only in the $z$ direction, whereas in the other two directions, $xy$ - planes, we consider ferromagnetic exchange. By implementing an effective parallel tempering scheme, we outline the phase diagram of the model and compare it to the corresponding isotropic one, as well as to a previously studied anisotropic (transverse) case. We present a detailed finite-size scaling analysis of the ferromagnetic - paramagnetic and spin glass - paramagnetic transition lines, and we also discuss the ferromagnetic - spin glass transition regime. We conclude that the present model shares the same universality classes with the isotropic model, but at the symmetric point has a considerably higher transition temperature from the spin-glass state to the paramagnetic phase. Our data for the ferromagnetic - spin glass transition line are supporting a forward behavior in contrast to the reentrant behavior of the isotropic model.

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T. Papakonstantinou, N. G. Fytas, A. Malakis, I. Lelidis. 2014-10-30. Critical aspects of three-dimensional anisotropic spin-glass models. https://doi.org/10.1140/epjb/e2015-50864-4

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