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arXiv · 1111.3749

Metamagnetic Behavior and Kondo Breakdown in Heavy-Fermion CeFePO

S. Kitagawa·H. Ikeda·Y. Nakai·T. Hattori·K. Ishida·Y. Kamihara·M. Hirano·H. Hosono
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Abstract

We report that nonmagnetic heavy-fermion (HF) iron oxypnictide CeFePO with two-dimensional XY-type anisotropy shows a metamagnetic behavior at the metamagnetic field H_M \simeq 4 T perpendicular to the c-axis and that a critical behavior is observed around H_M. Although the magnetic character is entirely different from that in other Ce-based HF metamagnets, H_M in these metamagnets is linearly proportional to the inverse of the effective mass, or to the temperature where the susceptibility shows a peak. This finding suggests that H_M is a magnetic field breaking the local Kondo singlet, and the critical behavior around H_M is driven by the Kondo breakdown accompanied by the Fermi-surface instability.

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S. Kitagawa, H. Ikeda, Y. Nakai, T. Hattori, K. Ishida, Y. Kamihara, M. Hirano, H. Hosono. 2012-01-16. Metamagnetic Behavior and Kondo Breakdown in Heavy-Fermion CeFePO. https://doi.org/10.1103/physrevlett.107.277002

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