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arXiv · 1112.3169

The reason why doping causes superconductivity in LaFeAsO

Ekkehard Krüger·Horst P. Strunk
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Abstract

The experimental observation of superconductivity in LaFeAsO appearing on doping is analyzed with the group-theoretical approach that evidently led in a foregoing paper (J. Supercond 24:2103, 2011) to an understanding of the cause of both the antiferromagnetic state and the accompanying structural distortion in this material. Doping, like the structural distortions, means also a reduction of the symmetry of the pure perfect crystal. In the present paper we show that this reduction modifies the correlated motion of the electrons in a special narrow half-filled band of LaFeAsO in such a way that these electrons produce a stable superconducting state.

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Ekkehard Krüger, Horst P. Strunk. 2011-12-14. The reason why doping causes superconductivity in LaFeAsO. https://doi.org/10.1007/s10948-012-1408-5

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