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arXiv · 2003.11601

Dualism of the 4f electrons and high-temperature antiferromagnetism of the heavy-fermion compound YbCoC$_{2}$

D. A. Salamatin·N. Martin·V. A. Sidorov·N. M. Chtchelkatchev·M. V. Magnitskaya·A. E. Petrova·I. P. Zibrov·L. N. Fomicheva·Jing Guo·Cheng Huang·Liling Sun·A. V. Tsvyashchenko
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Abstract

We report on the first study of the noncentrosymmetric ternary carbide YbCoC$_{2}$. Our magnetization, specific heat, resistivity and neutron diffraction measurements consistently show that the system behaves as a heavy-fermion compound, displaying an amplitude-modulated magnetic structure below the N\'eel temperature reaching $T_{N}$ = 33 K under pressure. Such a large value, being the highest among the Yb-based systems, is explained in the light of our ab initio calculations, which show that the 4f electronic states of Yb have a dual nature -- i.e., due to their strong hybridization with the 3d states of Co, 4f states expose both localized and itinerant properties.

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D. A. Salamatin, N. Martin, V. A. Sidorov, N. M. Chtchelkatchev, M. V. Magnitskaya, A. E. Petrova, I. P. Zibrov, L. N. Fomicheva, Jing Guo, Cheng Huang, Liling Sun, A. V. Tsvyashchenko. 2020-03-25. Dualism of the 4f electrons and high-temperature antiferromagnetism of the heavy-fermion compound YbCoC$_{2}$. https://doi.org/10.1103/physrevb.101.100406

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