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arXiv · 0801.4445

Comparative study of ordered and disordered Y1-xSrxCoO3-d

S. Fukushima·T. Sato·D. Akahoshi·H. Kuwahara
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Abstract

We have succeeded in preparing A-site ordered- and disordered-Y1/4Sr3/4CoO3-d with various oxygen deficiencies delta, and have made comparative study of their structural and physical properties. In the A-site ordered structure, oxygen vacancies order, and d = 0.34 sample shows a weak ferromagnetic transition beyond 300 K. On the other hand, in the A-site disordered structure, no oxygen vacancy ordering is observed, and d = 0.16 sample shows a ferromagnetic metallic transition around 150 K. A-site disordering destroys the orderings of oxygen-vacancies and orbitals, leading to the strong modification of the electronic phases.

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S. Fukushima, T. Sato, D. Akahoshi, H. Kuwahara. 2008-01-29. Comparative study of ordered and disordered Y1-xSrxCoO3-d. https://doi.org/10.1063/1.2830615

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