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Direct Observation of High-Temperature Polaronic Behavior In Colossal Magnetoresistive Manganites

N. Mannella·A. Rosenhahn·C. H. Booth·S. Marchesini·B. S. Mun·S. -H. Yang·K. Ibrahim·Y. Tomioka·C. S. Fadley
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Abstract

The temperature dependence of the electronic and atomic structure of the colossal magnetoresistive oxides $La_{1-x}Sr_{x}MnO_{3}$ (x = 0.3, 0.4) has been studied using core and valence level photoemission, x-ray absorption and emission, and extended x-ray absorption fine structure spectroscopy. A dramatic and reversible change of the electronic structure is observed on crossing the Curie temperature, including charge localization and spin moment increase of Mn, together with Jahn-Teller distortions, both signatures of polaron formation. Our data are also consistent with a phase-separation scenario.

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N. Mannella, A. Rosenhahn, C. H. Booth, S. Marchesini, B. S. Mun, S. -H. Yang, K. Ibrahim, Y. Tomioka, C. S. Fadley. 2004-01-15. Direct Observation of High-Temperature Polaronic Behavior In Colossal Magnetoresistive Manganites. https://doi.org/10.1103/physrevlett.92.166401

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