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arXiv · 0804.0536

Orbital Degeneracy and the Microscopic Model of the FeAs Plane in the Iron-Based Superconductors

Tao Li
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Abstract

A microscopic model for the FeAs plane in the newly discovered Iron-based superconductors is proposed with the emphasis on the role of the orbital degeneracy between the Fe $3d_{xz}$ and $3d_{yz}$ orbital in the crystal field environment. The model predicts commensurate antiferromagnetic ordered ground state for the parent compounds and a d-wave superconducting ground state at finite doping. Inter-orbital couplings plays an interesting role in enhancing both orders. Correlated variational wave functions are proposed for both ordered phases.

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Tao Li. 2008-04-03. Orbital Degeneracy and the Microscopic Model of the FeAs Plane in the Iron-Based Superconductors. https://doi.org/10.1088/0953-8984%2F20%2F42%2F425203

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