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arXiv · 1109.2730

Large Magnetoresistance Effects in $Ln$CoAsO with a Ferromagnetic-Antiferromagnetic Transition

Hiroto Ohta·Chishiro Michioka·Kazuyoshi Yoshimura
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Abstract

A large magnetoresistance (MR) effect was observed in the layered compounds NdCoAsO and SmCoAsO, in which ferromagnetically ordered itinerant-electrons of Co are sandwiched by localized 4$f$-electrons of $Ln^{3+}$, below ferromagnetic-antiferromagnetic transition (FAFT) temperature $T_\mathrm{N}$ as observed in other FAFT compounds. In SmCoAsO, the large MR effect is also observed up to the Curie temperature $T_\mathrm{C}$, and it is found to be originating in the presence of another antiferromagnetic phase in the low-magnetic field region of the ferromagnetic phase.

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Hiroto Ohta, Chishiro Michioka, Kazuyoshi Yoshimura. 2011-09-13. Large Magnetoresistance Effects in $Ln$CoAsO with a Ferromagnetic-Antiferromagnetic Transition. https://doi.org/10.1103/physrevb.84.134411

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