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Novel Orbital Ordering induced by Anisotropic Stress in a Manganite Thin Film

Y. Wakabayashi·D. Bizen·H. Nakao·Y. Murakami·M. Nakamura·Y. Ogimoto·M. Izumi·K. Miyano·H. Sawa
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Abstract

We performed resonant and nonresonant x-ray diffraction studies of a Nd0.5Sr0.5MnO3 thin film that exhibits a clear first-order transition. Lattice parameters vary drastically at the metal-insulator transition at 170K (=T_MI), and superlattice reflections appear below 140K (=T_CO). The electronic structure between T_MI and T_CO is identified as A-type antiferromagnetic with the d_{x2-y2} ferroorbital ordering. Below T_CO, a new type of antiferroorbital ordering emerges. The accommodation of the large lattice distortion at the first-order phase transition and the appearance of the novel orbital ordering are brought about by the anisotropy in the substrate, a new parameter for the phase control.

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Y. Wakabayashi, D. Bizen, H. Nakao, Y. Murakami, M. Nakamura, Y. Ogimoto, M. Izumi, K. Miyano, H. Sawa. 2005-06-21. Novel Orbital Ordering induced by Anisotropic Stress in a Manganite Thin Film. https://doi.org/10.1103/physrevlett.96.017202

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