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arXiv · 0802.0072

Study of the low-temperature behavior of a disordered antiferromagnet with random fields by the parallel-tempering method

V. Prudnikov·A. Vakilov·E. Filikanov
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Abstract

The parallel-tempering method has been applied to numerically study the thermodynamic behavior of a three-dimensional disordered antiferromagnetic Ising model with random fields at spin concentrations corresponding to regions of both weak and strong structural disorder. An analysis of the low-temperature behavior of the model convincingly shows that in the case of a weakly disordered samples there is realized an antiferromagnetic ordered state, while in the region of strong structural disorder the effects of random magnetic fields lead to the realization of a new phase state of the system with a complex domain structure consisting of antiferromagnetic and ferromagnetic domains separated by regions of a spin-glass phase and characterized by a spinglass ground state.

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V. Prudnikov, A. Vakilov, E. Filikanov. 2008-02-01. Study of the low-temperature behavior of a disordered antiferromagnet with random fields by the parallel-tempering method. https://doi.org/10.1134/s0031918x07120010

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