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arXiv · 1605.03515

Avoided ferromagnetic quantum critical point: Antiferromagnetic ground state in substituted CeFePO

Anton Jesche·Tanita Balle·Kristin Kliemt·Christoph Geibel·Manuel Brando·Cornelius Krellner
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Abstract

We have investigated single crystals of two substitution series Ce(Ru$_{1-x}$Fe$_{x}$)PO and CeFe(As$_{1-y}$P$_{y}$)O in the vicinity to the quantum critical material CeFePO by means of magnetic-susceptibility and specific-heat measurements. We observe an antiferromagnetic ground state in the vicinity of the quantum critical point, with pronounced metamagnetic transitions for $H\parallel c$, which is the magnetically hard direction. Our results verify that a ferromagnetic quantum critical point is avoided in substituted CeFePO, because we clearly demonstrate that the ferromagnetic ground state changes into an antiferromagnetic one, when approaching the quantum critical point.

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Anton Jesche, Tanita Balle, Kristin Kliemt, Christoph Geibel, Manuel Brando, Cornelius Krellner. 2016-05-11. Avoided ferromagnetic quantum critical point: Antiferromagnetic ground state in substituted CeFePO. https://doi.org/10.1002/pssb.201600169

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