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arXiv · 1109.0929

Gutzwiller theory of band magnetism in LaOFeAs

Tobias Schickling·Florian Gebhard·Jörg Bünemann·Lilia Boeri·Ole K. Andersen·Werner Weber
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Abstract

We use the Gutzwiller variational theory to calculate the ground-state phase diagram and quasi-particle bands of LaOFeAs. The Fe3d--As4p Wannier-orbital basis obtained from density-functional theory defines the band part of our eight-band Hubbard model. The full atomic interaction between the electrons in the iron orbitals is parameterized by the Hubbard interaction U and an average Hund's-rule interaction J. We reproduce the experimentally observed small ordered magnetic moment over a large region of (U,J) parameter space. The magnetically ordered phase is a stripe spin-density wave of quasi-particles.

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Tobias Schickling, Florian Gebhard, Jörg Bünemann, Lilia Boeri, Ole K. Andersen, Werner Weber. 2011-09-05. Gutzwiller theory of band magnetism in LaOFeAs. https://doi.org/10.1103/physrevlett.108.036406

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