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arXiv · 2107.13131

Ce-site dilution in the ferromagnetic Kondo lattice CeRh$_6$Ge$_4$

Jia-Cheng Xu·Hang Su·Rohit Kumar·Shuai-Shuai Luo·Zhi-Yong Nie·An Wang·Feng Du·Rui Li·Michael Smidman·Hui-Qiu Yuan
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Abstract

The heavy fermion ferromagnet CeRh$_6$Ge$_4$ is the first example of a clean stoichiometric system where the ferromagnetic transition can be continuously suppressed by hydrostatic pressure to a quantum critical point. In order to reveal the outcome when the magnetic lattice of CeRh$_6$Ge$_4$ is diluted with non-magnetic atoms, this study reports comprehensive measurements of the physical properties of both single crystal and polycrystalline samples of La$_x$Ce$_{1-x}$Rh$_6$Ge$_4$. With increasing $x$, the Curie temperature decreases, and no transition is observed for $x$ $>$ 0.25, while the system evolves from exhibiting coherent Kondo lattice behaviors at low $x$, to the Kondo impurity scenario at large $x$. Moreover, non-Fermi liquid behavior (NFL) is observed over a wide doping range, which agrees well with the disordered Kondo model for 0.52 $\leq$ $x$ $\leq$ 0.66, while strange metal behavior is revealed in the vicinity of $x_c$ = 0.26.

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Jia-Cheng Xu, Hang Su, Rohit Kumar, Shuai-Shuai Luo, Zhi-Yong Nie, An Wang, Feng Du, Rui Li, Michael Smidman, Hui-Qiu Yuan. 2021-07-28. Ce-site dilution in the ferromagnetic Kondo lattice CeRh$_6$Ge$_4$. https://doi.org/10.1088/0256-307x%2F38%2F8%2F087101

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