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Spin-fluctuation dominated electrical transport of Ni3Al at high pressure

P. G. Niklowitz·F. Beckers·G. G. Lonzarich·G. Knebel·B. Salce·J. Thomasson·N. Bernhoeft·D. Braithwaite·J. Flouquet
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Abstract

We present the first study of a magnetic quantum phase transition in the itinerant-electron ferromagnet Ni3Al at high pressures. Electrical resistivity measurements in a diamond anvil cell at hydrostatic pressures up to 100 kbar and temperatures as low as 50 mK indicate that the Curie temperature collapses towards absolute zero at a critical pressure pc=82(2) kbar. Over wide ranges in pressure and temperature, both in the ferromagnetic and paramagnetic states, the temperature variation of the resistivity is found to deviate from the conventional Fermi-liquid form. We consider the extent to which this deviation can be understood in terms of a mean-field model of enhanced spin fluctuations on the border of ferromagnetism in three dimensions.

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P. G. Niklowitz, F. Beckers, G. G. Lonzarich, G. Knebel, B. Salce, J. Thomasson, N. Bernhoeft, D. Braithwaite, J. Flouquet. 2004-11-17. Spin-fluctuation dominated electrical transport of Ni3Al at high pressure. https://doi.org/10.1103/physrevb.72.024424

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