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arXiv · 0806.0123

Itinerant Ferromagnetism in layered crystals LaCoOX (X = P, As)

Hiroshi Yanagi·Ryuto Kawamura·Toshio Kamiya·Yoichi Kamihara·Masahiro Hirano·Tetsuya Nakamura·Hitoshi Osawa·Hideo Hosono
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Abstract

The electronic and magnetic properties of cobalt-based layered oxypnictides, LaCoOX (X = P, As), are investigated. LaCoOP and LaCoOAs show metallic type conduction, and the Fermi edge is observed by hard x-ray photoelectron spectroscopy. Ferromagnetic transitions occur at 43 K for LaCoOP and 66 K for LaCoOAs. Above the transition temperatures, temperature dependence of the magnetic susceptibility follows the Curie-Weiss law. X-ray magnetic circular dichroism (XMCD) is observed at the Co L2,3-edge, but not at the other edges. The calculated electronic structure shows a spin polarized ground state. These results indicate that LaCoOX are itinerant ferromagnets and suggest that their magnetic properties are governed by spin fluctuation.

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Hiroshi Yanagi, Ryuto Kawamura, Toshio Kamiya, Yoichi Kamihara, Masahiro Hirano, Tetsuya Nakamura, Hitoshi Osawa, Hideo Hosono. 2008-06-01. Itinerant Ferromagnetism in layered crystals LaCoOX (X = P, As). https://doi.org/10.1103/physrevb.77.224431

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