Magnetic-field tuned anisotropic quantum phase transition in the distorted kagome antiferromagnet Nd3BWO9

Fangyuan song; Han Ge; Andi Liu; Yuqi Qin; Yuyan Han; Langsheng Ling; Songliu Yuan; Zhongwen Ouyang; Jieming Sheng; Liusuo Wu; Zhaoming Tian

arXiv · 2311.03892

Magnetic-field tuned anisotropic quantum phase transition in the distorted kagome antiferromagnet Nd3BWO9

Fangyuan song·Han Ge·Andi Liu·Yuqi Qin·Yuyan Han·Langsheng Ling·Songliu Yuan·Zhongwen Ouyang·Jieming Sheng·Liusuo Wu·Zhaoming Tian

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Abstract

Rare-earth (RE) kagome-lattice magnets offer an excellent platform to discover the novel magnetic phase as well as quantum phase transition tuned by non-thermal control parameters, while the experimental realizations remain largely unexplored. Here, we report the discovery of magnetic-field (B)-induced anisotropic quantum phase transition in a distorted kagome antiferromagnet Nd3BWO9 with TN~0.32 K. The isothermal magnetizations at 0.05 K exhibit the spin-flop like metamagnetic crossover behaviors with different fractional magnetization anomalies for B perpendicular (B // c-axis) and parallel (B // a*-axis) to the kagome plane, respectively. In combination with the thermodynamic measurements, the field-temperature (B-T) phase diagrams for both field directions are constructed and that reveal the existence of several field-induced magnetic states. Along the c-axis, a proximate quantum bicritical point is observed near the metamagnetic crossover, which separates the low-field antiferromagnetic (AFM) phase and the intermediate AFM phase. While, for B // a*, another intermediate magnetic phase (IAFM2) appears between the low-field AFM phase and intermediate AFM (IAFM1) phase, giving rise to a tetracritical point. These results support the anisotropic field-induced metamagnetic quantum criticalities in Nd3BWO9, making it as a rare kagome antiferromagnet to investigate the quantum multi-criticality driven by spin frustration.

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Fangyuan song, Han Ge, Andi Liu, Yuqi Qin, Yuyan Han, Langsheng Ling, Songliu Yuan, Zhongwen Ouyang, Jieming Sheng, Liusuo Wu, Zhaoming Tian. 2023-11-07. Magnetic-field tuned anisotropic quantum phase transition in the distorted kagome antiferromagnet Nd3BWO9. https://arxiv.org/abs/2311.03892

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