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Helicoidal ordering in iron perovskites

Maxim Mostovoy
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Abstract

We consider magnetic ordering in materials with negative charge transfer energy, such as iron perovskite oxides. We show that for a large weight of oxygen holes in conduction bands, the double exchange mechanism favors a helicoidal rather than ferromagnetic spin ordering both in metals, e.g. SrFeO_3 and insulators with a small gap, e.g. CaFeO_3. We discuss the magnetic excitation spectrum and effects of pressure on magnetic ordering in these materials.

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Maxim Mostovoy. 2004-09-03. Helicoidal ordering in iron perovskites. https://doi.org/10.1103/physrevlett.94.137205

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