Local correlation effects on the s+-- and s++-wave superconductivities mediated by magnetic and orbital fluctuations in the 5-orbital Hubbard model for iron pnictides

Abstract

We investigate the electronic state and the superconductivity in the 5-orbital Hubbard model for iron pnictides by using the dynamical mean-field theory in conjunction with the Eliashberg equation. The renormalization factor exhibits significant orbital dependence resulting in the large change in the band dispersion as observed in recent ARPES experiments. The critical interactions towards the magnetic, orbital and superconducting instabilities are suppressed as compared with those from the random phase approximation (RPA) due to local correlation effects. Remarkably, the s++-pairing phase due to the orbital fluctuation is largely expanded relative to the RPA result, while the s+--pairing phase due to the magnetic fluctuation is reduced.

5 pages, 4 figures, minor changes, published in J. Phys. Soc. Jpn

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Cited by in corpus (5)

• Andreev spectroscopy of iron-based superconductors: temperature dependence of the order parameters and scaling of the ${\Delta }_{L,S}$ with $T_C$
• A High-Tc Mechanism of Iron Pnictide Superconductivity due to Cooperation of Ferro-orbital and Antiferromagnetic Fluctuations
• Fermi surface, pressure-induced antiferromagnetic order, and superconductivity in FeSe
• Hole-$s_{\pm }$ State Induced by Coexisting Ferro- and Aniferromagnetic and Aniferro-orbital Fluctuations in the Iron Pnictides
• Metal-insulator transition and superconductivity in the two-orbital Hubbard-Holstein model for iron-based superconductors