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arXiv · 2605.16059

Spherically symmetric approaches in the theoretical study of low-dimensional magnets

A. F. Barabanov·V. E. Valiulin·A. V. Mikheyenkov·P. S. Savchenkov
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Abstract

The main ideas and some of the most important results of the spherically symmetric self-consistent approach and a number of related theoretical algorithms are presented. These methods make it possible to study low-dimensional Heisenberg-type spin models, including frustrated ones, with careful consideration of the theoretic (Mermin-Wagner and Marshall) theorems, as well as the site spin constraint. Thus, the difficulties that may arise in the traditional analysis of low-dimensional magnetic systems are avoided. The approach can also be applied to the spin-pseudospin model, and is also embedded in more complex constructions when considering spin models with free carriers, such as the basic and three-band Hubbard models, t-J and s-d models, and the Kondo lattice.

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A. F. Barabanov, V. E. Valiulin, A. V. Mikheyenkov, P. S. Savchenkov. 2026-05-15. Spherically symmetric approaches in the theoretical study of low-dimensional magnets. https://doi.org/10.3367/ufne.2025.06.039948

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