Magnetic ordering in blocking layer and highly anisotropic electronic structure of high-Tc iron-based superconductor Sr2VFeAsO3: LDA+U study

We calculate electronic structures of a high-T-c iron-based superconductor Sr2VFeAsO3 by local-density approximation (LDA) plus U method. We assume a checkerboard antiferromagnetic order on its blocking layers including vanadium and strong correlation in d orbits of vanadium through the Hubbard U. While the standard LDA brings about metallic blocking layers and complicated Fermi surface as in the previous literatures, our calculation changes the blocking layer into insulating one and the Fermi surface becomes quite similar to those of other iron-based superconductors. Moreover, the appearance of the insulating blocking layers suggests high anisotropy on quasiparticle transports as experimental results and predicts new types of intrinsic Josephson effects.