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What drives the charge/orbital ordering in La0.5Sr1.5MnO4: Jahn-Teller distortion versus orbital ordering

U. Staub·V. Scagnoli·A. M. Mulders·M. Janousch·Z. Honda·J. M. Tonnerre
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Abstract

Temperature dependences of a magnetic and an orbital Bragg reflection at the Mn L2 and L3 edges of La0.5Sr1.5MnO4 have been collected. The temperature evolution of the orbital reflection depend strongly on the x-ray energy and reflects the different order parameteres for orbitals and Jahn-Teller distortions. The gradual increase of the orbital order parameter indicates that the orbital order and not the Jahn-Teller distortion drives the metal-insulator transition. Correspondingly, the orbital-orbital (super) exchange interaction dominates over the Jahn-Teller strain-field interaction.

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U. Staub, V. Scagnoli, A. M. Mulders, M. Janousch, Z. Honda, J. M. Tonnerre. 2006-03-20. What drives the charge/orbital ordering in La0.5Sr1.5MnO4: Jahn-Teller distortion versus orbital ordering. https://arxiv.org/abs/cond-mat/0603497

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