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Finite size spectrum, magnon interactions and magnetization of S=1 Heisenberg spin chains

Jizhong Lou·Shaojin Qin·Tai-Kai Ng·Zhaobin Su·Ian Affleck
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Abstract

We report our density matrix renormalization-group and analytical work on S=1 antiferromagnetic Heisenberg spin chains. We study the finite size behavior within the framework of the non-linear sigma model. We study the effect of magnon-magnon interactions on the finite size spectrum and on the magnetization curve close to the critical magnetic field, determine the magnon scattering length and compare it to the prediction from the non-linear $σ$ model.

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Jizhong Lou, Shaojin Qin, Tai-Kai Ng, Zhaobin Su, Ian Affleck. 1999-12-15. Finite size spectrum, magnon interactions and magnetization of S=1 Heisenberg spin chains. https://doi.org/10.1103/physrevb.62.3786

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