Hidetomo Usui

Unconventional pairing originating from the disconnected Fermi surfaces of superconducting LaFeAsO1-xFx.

For a newly discovered iron-based high T_{c} superconductor LaFeAsO1-xFx, we have constructed a minimal model, where inclusion of all five Fe d bands is found to be necessary. The random-phase approximation is applied to the model to investigate the origin of superconductivity. We conclude that the multiple spin-fluctuation modes arising from the nesting across the disconnected Fermi surfaces realize an extended s-wave pairing, while d-wave pairing can also be another candidate.

Minimal electronic models for superconducting BiS2layers

We construct minimal electronic models for a newly discovered superconductor LaO

Electronic Structure and Electron Correlation in LaFeAsO1-xFx and LaFePO1-xFx

{}_{1\ensuremath{-}x}

Two-orbital model explains the higher transition temperature of the single-layer Hg-cuprate superconductor compared to that of the La-cuprate superconductor.

F

Possible Three-Dimensional Nodes in the s± Superconducting Gap of BaFe2(As1-xPx)2

{}_{x}

Incommensurate spin fluctuations in hole-overdoped superconductor KFe2As2.

BiS

Minimum model and its theoretical analysis for superconducting materials with BiS2 layers

{}_{2}

Origin of the material dependence of Tc in the single-layered cuprates

(

Spin fluctuations and unconventional pairing in KFe2As2

{T}_{c}=10.6

Maximizing the Fermi-surface multiplicity optimizes the superconducting state of iron pnictide compounds

K) possessing BiS