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Massive triplet excitations in a magnetized anisotropic Haldane spin chain

A. Zheludev·Z. Honda·C. Broholm·K. Katsumata·S. M. shapiro·A. Kolezhuk·S. Park·Y. Qiu
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Abstract

Inelastic neutron scattering experiments on the Haldane-gap quantum antiferromagnet \nd are performed at mK temperatures in magnetic fields of almost twice the critical field $H_c$ applied perpendicular to the spin cahins. Above $H_c$ a re-opening of the spin gap is clearly observed. In the high-field Néel-ordered state the spectrum is dominated by three distinct long-lived excitation branches. Several field-theoretical models are tested in a quantitative comparison with the experimental data.

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A. Zheludev, Z. Honda, C. Broholm, K. Katsumata, S. M. shapiro, A. Kolezhuk, S. Park, Y. Qiu. 2003-01-24. Massive triplet excitations in a magnetized anisotropic Haldane spin chain. https://doi.org/10.1103/physrevb.68.134438

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