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Large-S approach to chiral phases in frustrated spin chains

A. K. Kolezhuk
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Abstract

A large-S approach to the description of chiral phases in frustrated antiferromagnetic spin-S chains with easy-plane anisotropy is proposed. The approach is valid in the vicinity of the classical Lifshitz point j=1/4, where j is the relative strength of the frustrating next-nearest-neighbor coupling. The effective theory turns out to be the nonlinear sigma-model with the additional fourth-order term in spatial derivatives. The topological term persists for j>1/4, which leads to disappearance of the chiral gapped phase for half-integer S, in accordance with the recent numerical results.

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A. K. Kolezhuk. 2002-02-10. Large-S approach to chiral phases in frustrated spin chains. https://doi.org/10.1143/ptps.145.29

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