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An experimental measurement of the staggered magnetization curve for a Haldane spin chain

A. Zheludev·E. Ressouche·S. Maslov·T. Yokoo·S. Raymond·J. Akimitsu
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Abstract

Long-range magnetic ordering in R_2 Ba Ni O_5 (R=magnetic rare earth) quasi-1-dimensional mixed-spin antiferromagnets is described by a simple mean-field model that is based on the intrinsic staggered magnetization function of isolated Haldane spin chains for the Ni-subsystem, and single-ion magnetization functions for the rare earth ions. The model is applied to new experimental results obtained in powder diffraction experiments on Nd_2 Ba Ni O_5 and Nd Y Ba Ni O_5, and to previously published diffraction data for Er_2 Ba Ni O_5. From this analysis we extract the bare staggered magnetization curve for Haldane spin chains in these compounds.

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A. Zheludev, E. Ressouche, S. Maslov, T. Yokoo, S. Raymond, J. Akimitsu. 1998-03-09. An experimental measurement of the staggered magnetization curve for a Haldane spin chain. https://doi.org/10.1103/physrevlett.80.3630

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