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Finite size induced phenomena in 2D classical spin models

O. Kapikranian·B. Berche·Yu. Holovatch
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Abstract

We make a short overview of the recent analytic and numerical studies of the classical two-dimensional XY and Heisenberg models at low temperatures. Special attention is being paid to an influence of finite system size L on the peculiarities of the low-temperature phase. In accordance with the Mermin-Wagner-Hohenberg theorem, spontaneous magnetisation does not appear in the above models at infinite L. However it emerges for the finite system sizes and leads to new features of the low-temperature behaviour.

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O. Kapikranian, B. Berche, Yu. Holovatch. 2006-12-09. Finite size induced phenomena in 2D classical spin models. https://arxiv.org/abs/cond-mat/0612231

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