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Orbital Structure and Magnetic Ordering in Layered Manganites: Universal Correlation and Its Mechanism

S. Okamoto·S. Ishihara·S. Maekawa
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Abstract

Correlation between orbital structure and magnetic ordering in bilayered manganites is examined. A level separation between the $3d_{3z^2-r^2}$ and $3d_{x^2-y^2}$ orbitals in a Mn ion is calculated in the ionic model for a large number of the compounds. It is found that the relative stability of the orbitals dominates the magnetic transition temperatures as well as the magnetic structures. A mechanism of the correlation between orbital and magnetism is investigated based on the theoretical model with the two $e_g$ orbitals under strong electron correlation.

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S. Okamoto, S. Ishihara, S. Maekawa. 2000-01-17. Orbital Structure and Magnetic Ordering in Layered Manganites: Universal Correlation and Its Mechanism. https://doi.org/10.1103/physrevb.63.104401

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