High temperature singlet-based magnetism from Hund’s rule correlations
High temperature singlet-based magnetism from Hund’s rule correlations
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DOI：
10.1038/s41467-019-08497-3
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发表时间：
2019-02
影响因子：
16.6
通讯作者：
L. Miao;Rourav Basak;S. Ran;Yishuai Xu;Erica Kotta;Haowei He;J. Denlinger;Y. Chuang;Yang Zhao;Zhijun Xu;J. Lynn;J. Jeffries;S. Saha;I. Giannakis;P. Aynajian;Chang‐Jong Kang;Yilin Wang;G. Kotliar;N. Butch;L. Wray
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文献类型：
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作者：
L. Miao;Rourav Basak;S. Ran;Yishuai Xu;Erica Kotta;Haowei He;J. Denlinger;Y. Chuang;Yang Zhao;Zhijun Xu;J. Lynn;J. Jeffries;S. Saha;I. Giannakis;P. Aynajian;Chang‐Jong Kang;Yilin Wang;G. Kotliar;N. Butch;L. Wray
铀化合物可以表现出各种令人着迷的多体现象，并且通常被认为处于 5f 电子局域和流动状态之间的交叉状态。由于发现了丰富的近似相图和不寻常的量子相干现象，反铁磁二镍化物 USb2 最近引起了人们的兴趣。在这里，线性二向色 X 射线吸收和弹性中子散射用于表征 USb2 和同构 UBi2 中铀的电子对称性。在这两种材料中，只有 USb2 能够实现局部磁自由度的强洪德规则排列，并且在整个磁相变过程中局部原子多重对称性发生独特的变化。理论分析表明，该材料的这些和其他异常性质可以通过将其归因于第一个已知的单线态基态磁体的高温实现来理解，其中磁性通过类似于激子凝聚的过程发生。
Uranium compounds can manifest a wide range of fascinating many-body phenomena, and are often thought to be poised at a crossover between localized and itinerant regimes for 5felectrons. The antiferromagnetic dipnictide USb2has been of recent interest due to the discovery of rich proximate phase diagrams and unusual quantum coherence phenomena. Here, linear-dichroic X-ray absorption and elastic neutron scattering are used to characterize electronic symmetries on uranium in USb2and isostructural UBi2. Of these two materials, only USb2is found to enable strong Hund’s rule alignment of local magnetic degrees of freedom, and to undergo distinctive changes in local atomic multiplet symmetry across the magnetic phase transition. Theoretical analysis reveals that these and other anomalous properties of the material may be understood by attributing it as the first known high temperature realization of a singlet ground state magnet, in which magnetism occurs through a process that resembles exciton condensation.