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arXiv · 1009.1702

Antisite Domains in Double Perovskite Ferromagnets: Impact on Magnetotransport and Half-metallicity

Viveka Nand Singh·Pinaki Majumdar
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Abstract

Several double perovskite materials of the form A_2BB'O_6 exhibit high ferromagnetic T_c, and significant low field magnetoresistance. They are also a candidate source of spin polarized electrons. The potential usefulness of these materials is, however, frustrated by mislocation of the B and B' ions, which do not organise themselves in the ideal alternating structure. The result is a strong dependence of physical properties on preparative conditions, reducing the magnetization and destroying the half-metallicity. We provide the first results on the impact of spatially correlated antisite disorder, as observed experimentally, on the ferromagnetic double perovskites. The antisite domains suppress magnetism and half-metallicity, as expected, but lead to a dramatic enhancement of the low field magnetoresistance.

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Viveka Nand Singh, Pinaki Majumdar. 2010-09-09. Antisite Domains in Double Perovskite Ferromagnets: Impact on Magnetotransport and Half-metallicity. https://doi.org/10.1209/0295-5075%2F94%2F47004

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