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arXiv · 0804.2480

Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides

Qimiao Si·Elihu Abrahams
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Abstract

We consider the iron pnictides in terms of a proximity to a Mott insulator. The superexchange interactions contain competing nearest-neighbor and next-nearest-neighbor components. In the undoped parent compound, these frustrated interactions lead to a two-sublattice collinear antiferromagnet (each sublattice forming a Neel ordering), with a reduced magnitude for the ordered moment. Electron or hole doping, together with the frustration effect, suppresses the magnetic ordering and allows a superconducting state. The exchange interactions favor a d-wave superconducting order parameter; in the notation appropriate for the Fe square lattice, its orbital symmetry is $d_{xy}$. A number of existing and future experiments are discussed in light of the theoretical considerations.

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Qimiao Si, Elihu Abrahams. 2008-08-04. Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides. https://doi.org/10.1103/physrevlett.101.076401

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