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arXiv · 0705.4243

Polaronic state and nanometer-scale phase separation in colossal magnetoresistive manganites

Sahana Roessler·S. Ernst·B. Padmanabhan·Suja Elizabeth·H. L. Bhat·F. Steglich·S. Wirth
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Abstract

High resolution topographic images obtained by scanning tunneling microscope in the insulating state of Pr0.68Pb0.32MnO3 single crystals showed regular stripe-like or zigzag patterns on a width scale of 0.4 - 0.5 nm confirming a high temperature polaronic state. Spectroscopic studies revealed inhomogeneous maps of zero-bias conductance with small patches of metallic clusters on length scale of 2 - 3 nm only within a narrow temperature range close to the metal-insulator transition. The results give a direct observation of polarons in the insulating state, phase separation of nanometer-scale metallic clusters in the paramagnetic metallic state, and a homogeneous ferromagnetic state.

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Sahana Roessler, S. Ernst, B. Padmanabhan, Suja Elizabeth, H. L. Bhat, F. Steglich, S. Wirth. 2007-05-29. Polaronic state and nanometer-scale phase separation in colossal magnetoresistive manganites. https://doi.org/10.1209/0295-5075/83/17009

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