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Field-induced commensurate long-range order in the Haldane-gap system NDMAZ

A. Zheludev·Z. Honda·K. katsumata·R. feyerherm·K. Prokes
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Abstract

High-field neutron diffraction studies of the new quantum-disordered S=1 linear-chain antiferromagnet Ni(C$_5$H$_{14}$N$_2$)$_2$N$_3$(ClO$_4$) (NDMAZ) are reported. At T=70 mK, at a critical field $H_c=13.4$ T applied along the (013) direction, a phase transition to a commensurate Néel-like ordered state is observed. The results are discussed in the context of existing theories of quantum phase transitions in Haldane-gap antiferromagnets, and in comparions with previous studies of the related system Ni(C$_5$H$_{14}$N$_2$)$_2$N$_3$(PF$_6$).

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A. Zheludev, Z. Honda, K. katsumata, R. feyerherm, K. Prokes. 2001-04-17. Field-induced commensurate long-range order in the Haldane-gap system NDMAZ. https://doi.org/10.1209/epl%2Fi2001-00362-7

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