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Quasi-elastic neutron scattering in the high-field phase of a Haldane antiferromagnet

A. Zheludev·Z. Honda·Y. Chen·C. L. Broholm·K. Katsumata
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Abstract

Inelastic neutron scattering experiments on the Haldane-gap quantum antiferromagnet NDMAP are performed in magnetic fields below and above the critical field Hc at which the gap closes. Quasi-elastic neutron scattering is found for H>Hc indicating topological excitations in the high field phase.

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A. Zheludev, Z. Honda, Y. Chen, C. L. Broholm, K. Katsumata. 2001-12-12. Quasi-elastic neutron scattering in the high-field phase of a Haldane antiferromagnet. https://doi.org/10.1103/physrevlett.88.077206

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