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A microscopic approach to the dimerization in the frustrated spin-1/2 antiferromagnetic chains

Yang Xian
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Abstract

The spontaneous dimerization of the frustrated spin-$1\over2$ antiferromagnetic chains is studied by a microscopic approach based on a proper set of composite operators (i.e., pseudo-spin operators). Two approximation schemes are developed. Firstly, a spin-wave approximation is made by a Dyson-Maléev-like boson transformation. The ground-state properties and the triplet excitation spectra are obtained as functions of the coupling parameter. Secondly, based on the pseudo-spin operators, a microscopic treatment is formulated within the framework of the powerful, systematic coupled-cluster method (CCM). Comparison between various approximations is made. The advantage of the CCM for the purposes of systematic improvement is emphasized.

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Yang Xian. 1994-04-28. A microscopic approach to the dimerization in the frustrated spin-1/2 antiferromagnetic chains. https://doi.org/10.1088/0953-8984%2F6%2F30%2F015

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