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arXiv · 0807.2412

Competing orders in FeAs layers

J. Lorenzana·G. Seibold·C. Ortix·M. Grilli
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Abstract

Using the unrestricted Hartree-Fock approximation and Landau theory we identify possible phases competing with superconductivity in FeAs layers. We find that close to half-filling the transition from the paramagnet to the magnetically ordered phase is first-order making anharmonicities relevant and leading to a rich phase diagram. Between the already known one dimensionally modulated magnetic stripe phase and the paramagnet we find a new phase which has the same structure factor as the former but in which magnetic moments at nearest-neighbor sites are at right angles making electrons to acquire a non trivial phase when circulating a plaquette at strong coupling. Another competing phase has magnetic and charge order and may be stabilized by charged impurities.

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J. Lorenzana, G. Seibold, C. Ortix, M. Grilli. 2008-07-15. Competing orders in FeAs layers. https://doi.org/10.1103/physrevlett.101.186402

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