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arXiv · 1007.4814

Relationship between orbital structure and lattice distortions: CE phase of manganites, revisited

A. O. Sboychakov·K. I. Kugel·A. L. Rakhmanov·D. I. Khomskii
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Abstract

Analyzing the orbital structure and lattice distortions in the CE phase of half-doped manganites, we demonstrate that the usual approach directly relating the orbital occupation of Jahn-Teller ions to the displacements of neighboring ligands may be misleading. For the correct identification of orbital structure, it is necessary to take self-consistently into account the electron-lattice interactions, kinetic energy of charge carriers, and crystal-field effects. In certain situations, e.g. in the CE phase of single-layered manganite La$_{0.5}$Sr$_{1.5}$MnO$_4$, the type of orbital ordering strongly deviates from that, which one would deduce from the local lattice distortions.

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A. O. Sboychakov, K. I. Kugel, A. L. Rakhmanov, D. I. Khomskii. 2010-07-27. Relationship between orbital structure and lattice distortions: CE phase of manganites, revisited. https://doi.org/10.1103/physrevb.83.205123

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