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arXiv · 0806.2819

Identification of a Marginal Fermi-Liquid in Itinerant Ferromagnet CoS2

M. Otero-Leal·F. Rivadulla·M. Garcia-Hernandez·A. Pineiro·V. Pardo·D. Baldomir·J. Rivas
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Abstract

We report specific heat, resistivity and susceptibility measurements at different temperatures, magnetic fields, and pressures to provide solid evidence of CoS2 being a marginal Fermi liquid. The presence of a tricritical point in the phase diagram of the system provides an opportunity to test the spin fluctuation theory with a high limit of accuracy. A magnetic field suppresses the amplitude of the spin fluctuations and recovers conventional Fermi liquid behavior, connecting both states continuously.

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M. Otero-Leal, F. Rivadulla, M. Garcia-Hernandez, A. Pineiro, V. Pardo, D. Baldomir, J. Rivas. 2008-06-17. Identification of a Marginal Fermi-Liquid in Itinerant Ferromagnet CoS2. https://arxiv.org/abs/0806.2819

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