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Impurity-impurity pair correlation function and paramagnetic-ferromagnetic phase transition in the random Ising model

D. Ivaneyko·B. Berche·Yu. Holovatch·Ja. Ilnytskyi
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Abstract

In this Monte Carlo study we concentrated on the influence of non-magnetic impurities arranged as the lines with random orientation on paramagnetic-to-ferromagnetic phase transition in the 3D Ising model. Special emphasize is given to the long-distance decay of the impurity-impurity pair correlation function. It is shown that for the lattice sizes considered (L=10-96) and for the two different impurity distributions (purely random and mutually avoiding lines) the function is governed by the power law of 1/r^a with an universal exponent a \simeq 2. This result supports our findings about the numerical values of the critical exponents governing magnetic phase transition in the 3D Ising model with long-range-correlated disorder.

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D. Ivaneyko, B. Berche, Yu. Holovatch, Ja. Ilnytskyi. 2006-11-30. Impurity-impurity pair correlation function and paramagnetic-ferromagnetic phase transition in the random Ising model. https://arxiv.org/abs/cond-mat/0611778

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