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Multi-particle States in Spin-1 Chain System CsNiCl3

M. Kenzelmann·R. A. Cowley·W. J. L. Buyers·R. Coldea·J. S. Gardner·M. Enderle·D. F. McMorrow·S. M. Bennington
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Abstract

A continuum of magnetic states has been observed by neutron scattering from the spin-1 chain compound CsNiCl3 in its disordered gapped one-dimensional phase. Results using both triple-axis and time-of-flight spectrometers show that around the antiferromagnetic point Qc=pi, the continuum lies higher in energy than the Haldane gapped excitations. At 6K the integrated intensity of the continuum is about 12(2)% of the total spectral weight. This result is considerably larger than the 1-3% weight predicted by the non-linear sigma model for the 3-particle continuum.

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M. Kenzelmann, R. A. Cowley, W. J. L. Buyers, R. Coldea, J. S. Gardner, M. Enderle, D. F. McMorrow, S. M. Bennington. 2000-11-02. Multi-particle States in Spin-1 Chain System CsNiCl3. https://doi.org/10.1103/physrevlett.87.017201

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