Two-dimensional O(n) Models with Defects of "Random Local Anisotropy" Type

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

doi:10.1134/s1063783420040046

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arXiv · 1912.10444

Two-dimensional O(n) Models with Defects of "Random Local Anisotropy" Type

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

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Abstract

The phase diagram of two-dimensional systems with continuous symmetry of the vector order parameter containing defects of the "random local anisotropy" type is investigated. In the case of a weakly anisotropic distribution of the easy anisotropy axes in the space of the order parameter, with decreasing temperature, a smooth transition takes place from the paramagnetic phase with dynamic fluctuations of the order parameter to the Imri-Ma phase with its static fluctuations. In the case when the anisotropic distribution of the easy axes induces a global anisotropy of the "easy axis" type that exceeds a critical value, the system goes into the Ising class of universality, and a phase transition to the ordered state occurs in it at a finite temperature.

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A. A. Berzin, A. I. Morosov, A. S. Sigov. 2019-12-22. Two-dimensional O(n) Models with Defects of "Random Local Anisotropy" Type. https://doi.org/10.1134/s1063783420040046

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