686 citations · 1.9k across the 35 of their papers we have counts for
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Fourth-Order Perturbation Expansion for Hubbard Model on a Two-Dimensional Square Lattice
H. Ikeda, S. Shinkai, K. Yamada
We investigate the Hubbard model on a two-dimensional square lattice by the perturbation expansion to the fourth order in the on-site Coulomb repulsion U. Numerically calculating a…
Possible Pairing Symmetry of Three-dimensional Superconductor UPt -- Analysis Based on a Microscopic Calculation --
Shogo Shinkai, Kosaku Yamada
Stimulated by the anomalous superconducting properties of UPt, we investigate the pairing symmetry and the transition temperature in the two-dimensional(2D) and three-dimension…
Analysis of Superconductivity in d-p Model on Basis of Perturbation Theory
Sotaro Sasaki, Hiroaki Ikeda, Kosaku Yamada
We investigate the mass enhancement factor and the superconducting transition temperature in the d-p model for the high-$\Tc$ cuprates. We solve the Éliashberg equation using the t…
Calculation of Penetration Depth and in -ETCu(NCS) under Pressure
Kazunori Tanaka, Hiroaki Ikeda, Kosaku Yamada
The pressure dependence of the inverse square of the magnetic penetration depth in -ETCu(NCS) was measured by Larkin, et al According to the paper, $λ^{- 2…
Perturbation Analysis of Superconductivity in the Trellis-Lattice Hubbard Model
Sotaro Sasaki, Hiroaki Ikeda, Kosaku Yamada
We investigate pairing symmetry and transition temperature in the trellis-lattice Hubbard model. We solve the Éliashberg equation using the third-order perturbation theory with res…
Theory of Superconductivity in PuCoGa5
Kazunori Tanaka, Hiroaki Ikeda, Kosaku Yamada
Recently, superconductivity in PuCoGa5 was discovered. It has the same crystal structure as CeMIn5(M=Ir, Co, Rh). The electron correlation in PuCoGa5 is estimated to be weak compar…
Possible Pairing Symmetry of Superconductor Na_xCoO_2yH_2O
Yunori Nisikawa, Hiroaki Ikeda, Kosaku Yamada
To discuss a possibility that the superconductivities in Na_xCoO_2yH_2O are induced by the electron correlation, we investigate the possible pairing symmetry based on the single-ba…
Perturbation Theory for a Repulsive Hubbard Model in Quasi-One-Dimensional Superconductors
Sotaro Sasaki, Hiroaki Ikeda, Kosaku Yamada
We investigate pairing symmetry and a transition temperature in a quasi-one-dimensional repulsive Hubbard model. We solve the Eliashberg equation using the third-order perturbation…
Possibility of f-wave spin-triplet superconductivity in the CoO superconductor: a case study on a 2D triangular lattice in the repulsive Hubbard model
Hiroaki Ikeda, Yunori Nisikawa, Kosaku Yamada
Stimulated by the recent finding of NaCoO.1.3HO superconductor, we investigate superconducting instabilities on a 2D triangular lattice in the repulsive Hubbard mo…
Roles of Electron Correlations in the Spin-Triplet Superconductivity of Sr2RuO4
Takuji Nomura, Kosaku Yamada
We discuss a microscopic mechanism of the spin-tiplet superconductivity in the quasi-two-dimensional ruthenium oxide Sr2RuO4 on the basis of two-dimensional three-band Hubbard mode…
Perturbation Theory on the Transition Temperature and Electronic Properties of Organic Superconductor
T. Jujo, S. Koikegami, K. Yamada
We study the superconducting transition temperature and the electronic properties of the metallic phase of -type (BEDT-TTF)X which shows unconventional properties in experim…
A Possible Mechanism of the Pseudogap in Organic Superconductor Based on the Superconducting Fluctuation
T. Jujo, K. Yamada
The explanation of the anomalous behavior in -type (BEDT-TTF)X which was revealed by the nuclear magnetic resonance experiments is presented. We calculate the electronic pro…
Theory of Pseudogap Phenomena in High-Tc Cuprates Based on the Strong Coupling Superconductivity
Youichi Yanase, Kosaku Yamada
In this paper we study the effects of the strong coupling superconductivity on the normal state electronic structure. We point out that the pseudogap phenomena in High-T_c cuprates…