Quasi-one-dimensional Ising models with defects of the "random local field" type: Imry-Ma phase in spaces with dimension higher than the lower critical one

A. A. Berzin; A. I. Morosov; A. S. Sigov

doi:10.1134/s1063783421010042

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arXiv · 2005.08082

Quasi-one-dimensional Ising models with defects of the "random local field" type: Imry-Ma phase in spaces with dimension higher than the lower critical one

A. A. Berzin·A. I. Morosov·A. S. Sigov

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Abstract

The phase diagram in coordinates "temperature - concentration of defects" of quasi-one-dimensional Ising models with defects of the "random local field" type is investigated. The confrontation of the tendency to the emergence of the long-range order due to a weak interaction between one-dimensional spin chains and the tendency to the formation of the Imry-Ma phase in which the order parameter follows the fluctuations of the random field created by defects is studied. The possibility of the appearance of the Imry-Ma phase in a situation where the space dimension exceeds the lower critical dimension is shown. The question of the existence of the long-range order in the Ising model with random fields in space with the critical dimension dl = 2 is considered.

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BibTeX RIS

A. A. Berzin, A. I. Morosov, A. S. Sigov. 2020-05-16. Quasi-one-dimensional Ising models with defects of the "random local field" type: Imry-Ma phase in spaces with dimension higher than the lower critical one. https://doi.org/10.1134/s1063783421010042

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