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arXiv · 2209.11246

Neutron Depolarization due to Ferromagnetism and Spin Freezing in CePd$_{1-x}$Rh$_x$

M. Seifert·P. Schmakat·M. Schulz·P. Jorba·V. Hutanu·C. Geibel·M. Deppe·C. Pfleiderer
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Abstract

We report neutron depolarization measurements of the suppression of long-range ferromagnetism and the emergence of magnetic irreversibilities and spin freezing in CePd$_{1-x}$Rh$_x$ around $x^*\approx0.6$. Tracking the temperature versus field history of the neutron depolarization, we find clear signatures of long-range Ising ferromagnetism below a Curie temperature $T_{\rm C}$ for $x=0.4$ and a spin freezing of tiny ferromagnetic clusters below a freezing temperature $T_{\rm F1}$ for $x>x^*$. Under zero-field-cooling/field-heating and for $x>x^*$ a reentrant temperature dependence of the neutron depolarization between $T_{\rm F2}<T_{\rm F1}$ and $T_{\rm F1}$ is microscopically consistent with a thermally activated growth of the cluster size. The evolution of the depolarization as well as the reentrant temperature dependence as a function of Rh content are consistent with the formation of a Kondo-cluster glass below $T_{\rm F1}$ adjacent to a ferromagnetic quantum phase transition at $x^*$.

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M. Seifert, P. Schmakat, M. Schulz, P. Jorba, V. Hutanu, C. Geibel, M. Deppe, C. Pfleiderer. 2022-09-22. Neutron Depolarization due to Ferromagnetism and Spin Freezing in CePd$_{1-x}$Rh$_x$. https://doi.org/10.1103/physrevresearch.4.043029

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