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arXiv · 0910.5840

Quantum Griffiths phase in CePd(1-x)Rh(x) with x ~ 0.8

M. Brando·T. Westerkamp·M. Deppe·P. Gegenwart·C. Geibel·F. Steglich
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Abstract

The magnetic field dependence of the magnetisation ($M$) and the temperature dependence of the ac susceptibility ($\chi' = dM/dH$) of CePd(1-x)Rh(x) single crystals with $0.80 \leq x \leq 0.86$ are analysed within the frame of the quantum Griffiths phase scenario, which predicts $M \propto H^{\lambda}$ and $\chi' \propto T^{\lambda-1}$ with $0 \leq \lambda \leq 1$. All $M$ vs $H$ and $\chi'$ vs $T$ data follow the predicted power-law behaviour. The parameter $\lambda$, extracted from $\chi'(T)$, is very sensitive to the Rh content $x$ and varies systematically with $x$ from -0.1 to 0.4. The value of $\lambda$, derived from $M(H)$ measurements on a \cpr single crystal, seems to be rather constant, $\lambda \approx 0.2$, in a broad range of temperatures between 0.05 and 2 K and fields up to about 10 T. All observed signatures and the $\lambda$ values are thus compatible with the quantum Griffiths scenario.

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M. Brando, T. Westerkamp, M. Deppe, P. Gegenwart, C. Geibel, F. Steglich. 2009-10-30. Quantum Griffiths phase in CePd(1-x)Rh(x) with x ~ 0.8. https://doi.org/10.1088/1742-6596/200/1/012016

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