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Spin Fluctuations and the Magnetic Phase Diagram of ZrZn2

I. I. Mazin·D. J. Singh
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Abstract

The magnetic properties of the weak itinerant ferromagnet ZrZn_2 are analyzed using Landau theory based on a comparison of density functional calculations and experimental data as a function of field and pressure. We find that the magnetic properties are strongly affected by the nearby quantum critical point, even at zero pressure; LDA calculations neglecting quantum critical spin fluctuations overestimate the magnetization by a factor of approximately three. Using renormalized Landau theory, we extract pressure dependence of the fluctuation amplitude. It appears that a simple scaling based on the fluctuation-dissipation theorem provides a good description of this pressure dependence.

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I. I. Mazin, D. J. Singh. 2003-10-27. Spin Fluctuations and the Magnetic Phase Diagram of ZrZn2. https://doi.org/10.1103/physrevb.69.020402

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