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Dynamics of coupled quantum spin chains

H. J. Schulz
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Abstract

Static and dynamical properties of weakly coupled antiferromagnetic spin chains are treated using a mean--field approximation for the interchain coupling and exact results for the resulting effective one--dimensional problem. Results for staggered magnetization, Néel temperature and spin wave excitations are in agreement with experiments on $\rm KCuF_3$. The existence of a narrow longitudinal mode is predicted. The results are in agreement with general scaling arguments, contrary to spin wave theory.

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H. J. Schulz. 1996-04-25. Dynamics of coupled quantum spin chains. https://doi.org/10.1103/physrevlett.77.2790

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