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arXiv · 2202.13582

Suppression of ferromagnetism and influence of disorder in silicon-substituted CeRh6Ge4

Y. J. Zhang·Z. Y. Nie·R. Li·Y. C. Li·D. L. Yang·B. Shen·C. Ye·H. Su·R. Shi·S. Y. Wang·F. Steglich·M. Smidman·H. Q. Yuan
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Abstract

We report a study of isoelectronic chemical substitution in the recently discovered quantum critical ferromagnet CeRh$_6$Ge$_4$. Upon silicon-doping, the ferromagnetic ordering temperature of CeRh$_6$(Ge$_{1-x}$Si$_x$)$_4$ is continuously suppressed, and no transition is observed beyond $x_c$$\approx$0.125. Non-Fermi liquid behavior with $C/T \propto$log($T^*/T$) is observed close to $x_c$, indicating the existence of strong quantum fluctuations, while the $T$-linear behavior observed upon pressurizing the parent compound is absent in the resistivity, which appears to be a consequence of the disorder induced by silicon doping. Our findings provide evidence for the role played by disorder on the unusual ferromagnetic quantum criticality in CeRh$_6$Ge$_4$, and provides further evidence for understanding the origin of this behavior.

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Y. J. Zhang, Z. Y. Nie, R. Li, Y. C. Li, D. L. Yang, B. Shen, C. Ye, H. Su, R. Shi, S. Y. Wang, F. Steglich, M. Smidman, H. Q. Yuan. 2022-02-28. Suppression of ferromagnetism and influence of disorder in silicon-substituted CeRh6Ge4. https://doi.org/10.1103/physrevb.106.054409

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