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arXiv · 1006.4094

Signatures of a quantum Griffiths phase in a d-metal alloy close to its ferromagnetic quantum critical point

Almut Schroeder·Sara Ubaid-Kassis·Thomas Vojta
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Abstract

We report magnetization ($M$) measurements close to the ferromagnetic quantum phase transition of the d-metal alloy Ni$_{1-x}$V$_x$ at a vanadium concentration of $x_c \approx 11.4 %$. In the diluted regime ($x>x_c$), the temperature ($T$) and magnetic field ($H$) dependencies of the magnetization are characterized by nonuniversal power laws and display $H/T$ scaling in a wide temperature and field range. The exponents vary strongly with $x$ and follow the predictions of a quantum Griffiths phase. We also discuss the deviations and limits of the quantum Griffiths phase as well as the phase boundaries due to bulk and cluster physics.

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Almut Schroeder, Sara Ubaid-Kassis, Thomas Vojta. 2011-02-17. Signatures of a quantum Griffiths phase in a d-metal alloy close to its ferromagnetic quantum critical point. https://doi.org/10.1088/0953-8984%2F23%2F9%2F094205

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