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arXiv · 1003.0512

Unified Picture for Magnetic Correlations in Iron-Based Superconductors

Wei-Guo Yin·Chi-Cheng Lee·Wei Ku
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Abstract

The varying metallic antiferromagnetic correlations observed in iron-based superconductors are unified in a model consisting of both itinerant electrons and localized spins. The decisive factor is found to be the sensitive competition between the superexchange antiferromagnetism and the orbital-degenerate double-exchange ferromagnetism. Our results reveal the crucial role of Hund's rule coupling for the strongly correlated nature of the system and suggest that the iron-based superconductors are closer kin to manganites than cuprates in terms of their diverse magnetism and incoherent normal-state electron transport. This unified picture would be instrumental for exploring other exotic properties and the mechanism of superconductivity in this new class of superconductors.

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Wei-Guo Yin, Chi-Cheng Lee, Wei Ku. 2010-09-02. Unified Picture for Magnetic Correlations in Iron-Based Superconductors. https://doi.org/10.1103/physrevlett.105.107004

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