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Robust Half-Metallic Character and Large Oxygen Magnetism in a Perovskite Cuprate

Xiangang Wan·Masanori Kohno·Xiao Hu
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Abstract

The new perovskite cuprate material Sr$_{8}$CaRe$_{3}$Cu$_{4}$O$_{24}$, which behaves ferrimagnetically and shows an unusually high Curie temperature ($T_c \sim$ 440 K), is found from density-functional theory calculation to display several surprising properties after hole doping or chemical substitution: (1) Half metal (HM) is realized by replacing Re with W or Mo while $T_c$ remains high; (2) hole-doped Sr$_{8}$CaRe$_{3}$Cu$_{4}$O$_{24}$ is also HM with high $T_c$. Moreover, we find that the O atoms will carry a large magnetic moment after hole doping, which is in sharp contrast with the generally accepted concept that magnetism in solid requires partially filled shells of $d$ or $f$ electrons in cations. The material Sr$_8$CaRe$_3$Cu$_4$O$_{24}$ is therefore expected to provide a very useful platform for material design and development.

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Xiangang Wan, Masanori Kohno, Xiao Hu. 2005-05-17. Robust Half-Metallic Character and Large Oxygen Magnetism in a Perovskite Cuprate. https://doi.org/10.1103/physrevlett.95.146602

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