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arXiv · 0710.2278

Exploiting B Site Disorder for Phase Control in the Manganites

Kalpataru Pradhan·Anamitra Mukherjee·Pinaki Majumdar
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Abstract

Disorder on the active d element site is usually very disruptive for conduction and long range order in perovskite transition metal oxides. However, in the background of phase competition such `B site' dopants also act to promote one ordered phase at the expense of another. This occurs either through valence change of the transition metal or via creation of `defects' in the parent magnetic state. We provide a framework for understanding the complex variety of phenomena observed in B site doped manganites and identify the key parameters that control the physics. Using a spatially resolved analysis of B ions in various manganite phases we explain the existing data and predict new situations where highly polarisable phase separated states can be created.

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Kalpataru Pradhan, Anamitra Mukherjee, Pinaki Majumdar. 2008-11-21. Exploiting B Site Disorder for Phase Control in the Manganites. https://doi.org/10.1209/0295-5075/84/37007

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