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Modified self-consistent harmonic approximation and its application to two-dimensional easy-axis quantum ferromagnets

D. V. Spirin
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Abstract

In the paper we describe the modification of self-consistent harmonic approximation for quantum S=1 systems. This method has a number of advantages in comparison with usual SCHA. We apply the method to two-dimensional ferromagnets with easy-axis exchange or single-site anisotropy. The results are in good agreement with Monte-Carlo simulations and pure-quantum SCHA.

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D. V. Spirin. 2003-04-01. Modified self-consistent harmonic approximation and its application to two-dimensional easy-axis quantum ferromagnets. https://arxiv.org/abs/cond-mat/0303619

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