The anisotropy induced by defects of "random local field" type in O(n) models and suppression of the Imry-Ma inhomogeneous state

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

doi:10.1134/s1063783416080059

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arXiv · 1603.03360

The anisotropy induced by defects of "random local field" type in O(n) models and suppression of the Imry-Ma inhomogeneous state

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

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Abstract

We demonstrate that in the system with anisotropic distribution of the defect-induced random local field directions in the n-dimensional space of vector order parameter with the O(n) symmetry, the defect-induced effective anisotropy arises for the space dimensionality 2<d<4. If the anisotropy constant exceeds the threshold value, then an inhomogeneous state predicted by Imry and Ma becomes energetically unfavorable, and the system goes back to the state with the long-range order.

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A. A. Berzin, A. I. Morosov, A. S. Sigov. 2016-03-10. The anisotropy induced by defects of "random local field" type in O(n) models and suppression of the Imry-Ma inhomogeneous state. https://doi.org/10.1134/s1063783416080059

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