Spin density wave in oxypnictide superconductors in a three-band model
Dept. of Physics, and Institute for Condensed Matter Physics, School of
Physics and Telecommunication Engineering, South China Normal University, Guangzhou, 510006, P.R. China
Corresponding author: email@example.com
Revised: 10 April 2010
Published online: 6 May 2010
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, π) 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 Γ point indicating the formation of a paramagnetic phase. There is a clear transition from the SDW phase to the paramagnetic phase.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010