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arXiv · 2411.19538

Haldane phase, field-induced magnetic ordering and Tomonaga-Luttinger liquid behavior in a spin-one chain compound NiC$_2$O$_4$$\cdot$2NH$_3$

Shuo Li·Zhanlong Wu·Yanhong Wang·Jun Luo·Kefan Du·Xiaoyu Xu·Ze Hu·Ying Chen·Jie Yang·Zhengxin Liu·Rong Yu·Yi Cui·Rui Zhou·Hongcheng Lu·Weiqiang Yu
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Abstract

We performed single-crystal magnetic susceptibility and $^1$H NMR measurements on a quasi-1D, spin-1 antiferromagnet NiC$_2$O$_4$$\cdot$2NH$_3$, with temperature down to 100 mK and with field up to 26 T. With field applied along the chain direction (crystalline $b$ direction), a spin gap is determined at low fields. Our susceptibility and spin-lattice relaxation measurements reveal a Haldane phase at low field, with an intrachain exchange coupling $J$ $\approx$ 35 K and an easy-plane single-ion anisotropy of 17 K. A field-induced antiferromagnetic (AFM) ordering emerges at fields of 2.1 T, which sets a three-dimensional (3D) quantum critical point (QCP). The high-temperature spin-lattice relaxation rates $1/T_1$ resolves an onset of Tomonaga-Luttinger liquid behavior at field above $3.5$ T, which characterizes a hidden 1D QCP.

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Shuo Li, Zhanlong Wu, Yanhong Wang, Jun Luo, Kefan Du, Xiaoyu Xu, Ze Hu, Ying Chen, Jie Yang, Zhengxin Liu, Rong Yu, Yi Cui, Rui Zhou, Hongcheng Lu, Weiqiang Yu. 2024-11-29. Haldane phase, field-induced magnetic ordering and Tomonaga-Luttinger liquid behavior in a spin-one chain compound NiC$_2$O$_4$$\cdot$2NH$_3$. https://doi.org/10.1103/physrevb.111.195164

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