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arXiv · 1603.03687

A Mechanism of Long-Range Order Induced by Random Local Fields: Effective Anisotropy Created by Defects

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

We propose a microscopic mechanism of the long-range order in two-dimensional space induced by random local fields of crystal defects. The anisotropic distribution of defect-induced random local field directions in the n-dimensional space of vector order parameter with the O(n) symmetry is shown to give rise to the defect-induced effective anisotropy in the system. The expression for the effective anisotropy constant is found. A weak anisotropy of the "easy axis" type transforms the X-Y model and the Heisenberg model to the class of Ising models, and brings into existence the long-range order in the system.

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A. A. Berzin, A. I. Morosov, A. S. Sigov. 2016-03-11. A Mechanism of Long-Range Order Induced by Random Local Fields: Effective Anisotropy Created by Defects. https://doi.org/10.1134/s1063783416090109

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