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Nature of Orbital Ordering in La_0.5Sr_1.5MnO_4 is Studied by Soft X-ray Linear Dichroism

D. J. Huang·W. B. Wu·G. Y. Guo·H-J Lin·T. Y. Hou·C. F. Chang·C. T. Chen·A. Fujimori·Kimura·H. B. Huang·A. Tanaka·T. Jo
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Abstract

We found that the conventional model of orbital ordering of 3x^2-r^2/3y^2-r^2 type in the eg states of La_0.5Sr_1.5MnO_4 is incompatible with measurements of linear dichroism in the Mn 2p-edge x-ray absorption, whereas these eg states exhibit predominantly cross-type orbital ordering of x^2-z^2/y^2-z^2. LDA+U band-structure calculations reveal that such a cross-type orbital ordering results from a combined effect of antiferromagnetic structure, Jahn-Teller distortion, and on-site Coulomb interactions.

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D. J. Huang, W. B. Wu, G. Y. Guo, H-J Lin, T. Y. Hou, C. F. Chang, C. T. Chen, A. Fujimori, Kimura, H. B. Huang, A. Tanaka, T. Jo. 2003-12-30. Nature of Orbital Ordering in La_0.5Sr_1.5MnO_4 is Studied by Soft X-ray Linear Dichroism. https://doi.org/10.1103/physrevlett.92.087202

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