Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs

Z. P. Yin; S. Lebègue; M. J. Han; B. Neal; S. Y. Savrasov; W. E. Pickett

doi:10.1103/physrevlett.101.047001

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arXiv · 0804.3355

Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs

Z. P. Yin·S. Lebègue·M. J. Han·B. Neal·S. Y. Savrasov·W. E. Pickett

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Abstract

When either electron or hole doped at concentrations $x\sim 0.1$, the LaOFeAs family displays remarkably high temperature superconductivity with T$_c$ up to 55 K. In the most energetically stable $\vec Q_M = (π,π)$ antiferromagnetic (AFM) phase comprised of tetragonal-symmetry breaking alternating chains of aligned spins, there is a deep pseudogap in the Fe 3d states centered at the Fermi energy, and very strong magnetophonon coupling is uncovered. Doping (of either sign) beyond $x \sim 0.1$ results in Fe 3d heavy mass carriers ($m^*\sim 4-8$) with a large Fermi surface. Calculated Fe-Fe transverse exchange couplings $J_{ij}(R)$ reveal that exchange coupling is strongly dependent on the AFM symmetry and Fe-As distance.

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Z. P. Yin, S. Lebègue, M. J. Han, B. Neal, S. Y. Savrasov, W. E. Pickett. 2008-04-21. Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs. https://doi.org/10.1103/physrevlett.101.047001

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