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arXiv · 2001.03347

Emergence of quasiparticle multiplets in curium

Li Huang·Ruofan Chen·Haiyan Lu
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Abstract

A combination of the density functional theory and the single-site dynamical mean-field theory is employed to study the electronic structures of various allotropes of elemental curium (Cm-I, Cm-II, and Cm-III). We find that the 5$f$ valence electrons in the high-symmetry Cm-I and Cm-II phases remain localized, while they turn into itinerancy in the low-symmetry monoclinic Cm-III phase. In addition, conspicuous quasiparticle multiplets are identified in the 5$f$ electronic density of states of the Cm-III phase. We believe that it is the many-body transition between $5f^{7}$ and $5f^{8}$ configurations that gives rise to these quasiparticle multiplets. Therefore, the Cm-III phase is probably a new realization of the so-called Racah metal.

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Li Huang, Ruofan Chen, Haiyan Lu. 2020-01-10. Emergence of quasiparticle multiplets in curium. https://doi.org/10.1103/physrevb.101.195123

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