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arXiv · 0804.1891

Simultaneous suppression of ferromagnetism and superconductivity in UCoGe by Si substitution

D. E. de Nijs·N. T. Huy·A. de Visser
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Abstract

We investigate the effect of substituting Si for Ge in the ferromagnetic superconductor UCoGe. Dc-magnetization, ac-susceptibility and electrical resistivity measurements on polycrystalline UCoGe$_{1-x}$Si$_x$ samples show that ferromagnetic order and superconductivity are progressively depressed with increasing Si content and simultaneously vanish at a critical concentration $x_{cr} \simeq 0.12$. The non-Fermi liquid temperature variation in the electrical resistivity near $x_{cr}$ and the smooth depression of the ordered moment point to a continuous ferromagnetic quantum phase transition. Superconductivity is confined to the ferromagnetic phase, which provides further evidence for magnetically mediated superconductivity.

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D. E. de Nijs, N. T. Huy, A. de Visser. 2008-04-11. Simultaneous suppression of ferromagnetism and superconductivity in UCoGe by Si substitution. https://doi.org/10.1103/physrevb.77.140506

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