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arXiv · 1107.0983

Theory of Half-metallic Ferrimagnetism in Double Perovskites

Onur Erten·O. Nganba Meetei·Anamitra Mukherjee·Mohit Randeria·Nandini Trivedi·Patrick Woodward
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Abstract

We present a comprehensive theory of the temperature- and disorder-dependence of half-metallic ferrimagnetism in the double perovskite Sr$_2$FeMoO$_6$ (SFMO) with $T_c$ above room temperature. We show that the magnetization $M(T)$ and conduction electron polarization $P(T)$ are both proportional to the magnetization $M_S(T)$ of localized Fe spins. We derive and validate an effective spin Hamiltonian, amenable to large-scale three-dimensional simulations. We show how $M(T)$ and $T_c$ are affected by disorder, ubiquitous in these materials. We suggest a way to enhance $T_c$ in SFMO without sacrificing polarization.

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Onur Erten, O. Nganba Meetei, Anamitra Mukherjee, Mohit Randeria, Nandini Trivedi, Patrick Woodward. 2011-07-07. Theory of Half-metallic Ferrimagnetism in Double Perovskites. https://doi.org/10.1103/physrevlett.107.257201

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