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arXiv · 0704.2116

Ferromagnetic quantum critical point in URhGe doped with Ru

N. T. Huy·A. Gasparini·J. C. P. Klaasse·A. de Visser·S. Sakarya·N. H. van Dijk
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Abstract

We have investigated the thermal, transport and magnetic properties of URh$_{1-x}$Ru$_x$Ge alloys near the critical concentration $x_{cr} = 0.38$ for the suppression of ferromagnetic order. The Curie temperature vanishes linearly with $x$ and the ordered moment $m_0$ is suppressed in a continuous way. At $x_{cr}$ the specific heat varies as $c \sim TlnT$, the $\gamma$-value $c/T|_{0.5K}$ is maximum and the temperature exponent of the resistivity $\rho \sim T^n$ attains a minimum value $n=1.2$. These observations provide evidence for a ferromagnetic quantum phase transition. Interestingly, the coefficient of thermal expansion and the Gr\"uneisen parameter $\Gamma$ remain finite at $x_{cr}$ (down to $T = 1$ K), which is at odds with recent scaling results for a metallic quantum critical point.

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N. T. Huy, A. Gasparini, J. C. P. Klaasse, A. de Visser, S. Sakarya, N. H. van Dijk. 2007-04-17. Ferromagnetic quantum critical point in URhGe doped with Ru. https://doi.org/10.1103/physrevb.75.212405

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