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arXiv · 1304.1228

Ab-initio prediction of magnetoelectricity in infinite-layer CaFeO2 and MgFeO2

Kunihiko Yamauchi·Tamio Oguchi·Silvia Picozzi
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Abstract

Density functional based simulations are employed to explore magnetoelectric effects in iron-based oxides, showing a unique layered structure. We theoretically predict CaFeO2 to be a promising magnetoelectric, showing magnetically-controlled large electric polarization, possibly even above room temperature. The cross coupling between magnetic and dipolar degrees of freedom needs, as main ingredients, Fe-site spin-orbit coupling and a spin-dependent O p - Fe d hybridization, along with structural constraints related to the non-centrosymmetric point group and the peculiar geometry characterized by "flattened" FeO4 tetrahedrons. In order to enhance magnetoelectric effects, we performed a materials-design leading to a novel and optimized system, MgFeO2, where the larger O4 tetrahedral distortion leads to a stronger polarization.

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Kunihiko Yamauchi, Tamio Oguchi, Silvia Picozzi. 2013-04-04. Ab-initio prediction of magnetoelectricity in infinite-layer CaFeO2 and MgFeO2. https://doi.org/10.7566/jpsj.83.094712

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