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arXiv · 1004.4570

Spin density wave in oxypnictide superconductors in a three-band model

Mingsheng Long·Liangbin Hu·W. LiMing
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Abstract

The spin density wave and its temperature dependence in oxypnictide are studied in a three-band model. The spin susceptibilities with various interactions are calculated in the random phase approximation(PPA). It is found that the spin susceptibility peaks around the M point show a spin density wave(SDW) with momentum (0, $\pi$) and a clear stripe-like spin configuration. The intra-band Coulomb repulsion enhances remarkably the SDW but the Hund's coupling weakens it. It is shown that a new resonance appears at higher temperatures at the $\Gamma$ point indicating the formation of a paramagnetic phase. There is a clear transition from the SDW phase to the paramagnetic phase.

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Mingsheng Long, Liangbin Hu, W. LiMing. 2010-04-26. Spin density wave in oxypnictide superconductors in a three-band model. https://doi.org/10.1140/epjb/e2010-00141-3

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