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arXiv · 2306.08820

Ultrasonic investigation of the Kondo semimetal CeBi

Yupeng Pan·Xiaobo He·Shuo Zou·Hai Zeng·Yuqian Zhao·Ziyu Li·Yuesheng Li·Yongkang Luo
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Abstract

We report the elastic properties of the Kondo semimetal CeBi by resonant ultrasound spectroscopy measurements at zero magnetic field. Clear elastic softening is found in bulk modulus $C_B$ below $\sim 60$ K. Such a softening in $C_B$, in addition to the anomalous temperature dependent Poisson's ratio, is hardly attributable to multipolar response for stable localized $4f$ orbital, but can be well described by a two-band model arising from the hybridization between conduction- and $4f$- electrons. These results probably are consequences of the valence fluctuations in this Kondo semimetal as originally suggested by a Fermi-surface expansion observed in a previous angle-resolved photoemission spectroscopy study [P. Li \textit{et al.}, Phys. Rev. B $\mathbf{100}$, 155110 (2019)].

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Yupeng Pan, Xiaobo He, Shuo Zou, Hai Zeng, Yuqian Zhao, Ziyu Li, Yuesheng Li, Yongkang Luo. 2023-06-15. Ultrasonic investigation of the Kondo semimetal CeBi. https://doi.org/10.1103/physrevb.108.165153

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