Simultaneous suppression of ferromagnetism and superconductivity in UCoGe by Si substitution

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.

5 pages, 4 figures, accepted for publication in PRB

References in corpus (4)

• Superconductivity on the border of weak itinerant ferromagnetism in UCoGe
• Unusual upper critical field of the ferromagnetic superconductor UCoGe
• On the theory of superconductivity in ferromagnetic superconductors with triplet pairing
• Ferromagnetic quantum critical point in URhGe doped with Ru

Cited by in corpus (1)

• Ferromagnetic quantum critical point in UCo1-xFexGe