686 citations · 1.9k across the 35 of their papers we have counts for
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Study of Intrinsic Spin Hall Effect and Orbital Hall Effect in 4d- and 5d- Transition Metals
T. Tanaka, H. Kontani, M. Naito +4
We study the intrinsic spin Hall conductivity (SHC) in various -transition metals (Ta, W, Re, Os, Ir, Pt, and Au) and 4d-transition metals (Nb, Mo, Tc, Ru, Rh, Pd, and Ag) base…
Intrinsic anomalous Hall effect in ferromagnetic metals studied by the multi d-orbital tight-binding model
H. Kontani, T. Tanaka, K. Yamada
To elucidate the origin of anomalous Hall effect (AHE) in ferromagnetic transition metals, we study the intrinsic AHE based on a multi-orbital (xz,yz)-tight-binding model. We find…
Theoretical Study on Coexistence of Ferromagnetism and Superconductivity
Hirono Kaneyasu, Kosaku Yamada
On the basis of a two-dimensional t-t' Hubbard model in ferromagnetic and paramagnetic states, the triplet superconducting mechanism is investigated by the third-order perturbation…
Theory on Superconductivity of CeIn3 in Heavy Fermion System
Hirono Fukazawa, Kosaku Yamada
On the basis of a three-dimensional Hubbard model, the superconducting mechanism of CeIn3 under high pressure is investigated by the third-order perturbation theory with respect to…
Fourth Order Perturbation Theory for Normal Selfenergy in Repulsive Hubbard Model
Shogo Shinkai, Hiroaki Ikeda, Kosaku Yamada
We investigate the normal selfenergy and the mass enhancement factor in the Hubbard model on the two-dimensional square lattice. Our purpose in this paper is to evaluate the mass e…
From Kondo Effect to Fermi Liquid
Hiroshi Kontani, Kosaku Yamada
The Kondo effect has been playing an important role in strongly correlated electon systems. The important point is that the magnetic impurity in metals is a typical example of the…
Reduction of Tc due to Impurities in Cuprate Superconductors
Kiwamu Kudo, Kosaku Yamada
In order to explain how impurities affect the unconventional superconductivity, we study non-magnetic impurity effect on the transition temperature using on-site U Hubbard model wi…
Theory of Superconductivity in Strongly Correlated Electron Systems
Yoichi Yanase, Takanobu Jujo, Takuji Nomura +3
In this article we review essential natures of superconductivity in strongly correlated electron systems (SCES) from a universal point of view. After summarizing experimental resul…
A Mechanism of Spin-Triplet Superconductivity in Hubbard Model on Triangular La ttice: Application to UNi_2Al_3
Yunori Nisikawa, Kosaku Yamada
We discuss the possibility of spin-triplet superconductivity in a two-dimensional Hubbard model on a triangular lattice within the third-order perturbation theory. When we vary the…
Role of Vertex Correction and Dimensionality on Superconductivity Induced by On-site Coulomb Repuls ion
Hirono Fukazawa, Hiroaki Ikeda, Kosaku Yamada
We evaluate the dominant superconducting pairing symmetry in some 3-dimensional cubic lattice struct ures within the third-order perturbation theory with respect to the on-site cou…
Third Order Perturbation Analysis of Pairing Symmetry in Two-Dimensional Hubbard Model
Hirono Fukazawa, Kosaku Yamada
We study the superconducting instabilities of singlet and triplet pairing in a two-dimensional Hubbard model on the basis of the third-order perturbation theory (TOPT). We investig…
Perturbation Theory on the Superconductivity of Heavy Fermion Superconductors CeIr_{x}Co_{1-x}In_5
Yunori Nisikawa, Hiroaki Ikeda, Kosaku Yamada
We reformulate the Eliashberg's equation for the superconducting transition within the quasi-particle description, which takes account of the heavy electron mass. We discuss the su…
Perturbation Theory on the Superconductivity of Heavy Fermion Superconductor UPd_2Al_3
Yunori Nisikawa, Kosaku Yamada
We investigate the superconducting mechanism and the transition temperature of heav y fermion superconductor UPd_2Al_3 on the basis of a single band two-dimensional Hubbard model o…
Pseudogap Phenomena and Superconducting Fluctuations in Hubbard Model for High-Tc Cuprates
Youichi Yanase, Kosaku Yamada
The pseudogap phenomena in High- cuprates are investigated on the basis of the Hubbard model which includes only the on-site repulsive interaction . We consider the p…
Theory on Superconducting Transition from Pseudogap State
Youichi Yanase, Takanobu Jujo, Kosaku Yamada
The anomalous properties of High- cuprates are investigated both in the normal state and in the superconducting state. In particular, we pay atte ntion to the pseudogap…
Spin Susceptibility and Specific Heat in the d-p Model
Shigeru Koikegami, Kosaku Yamada
We analyze the two-dimensional {\it d-p} model, considering both antiferromagnetic spin fluctuation and -wave superconducting fluctuation. We adopt the fluctuation-exc…
Effect of Magnetic field on the Pseudogap Phenomena in High-Tc Cuprates
Youichi Yanase, Kosaku Yamada
We theoretically investigate the effect of magnetic field on the pseudogap phenomena in High-Tc cuprates. The obtained results well explain the experimental results including their…
Electronic State and Magnetic Susceptibility in Orbitally Degenerate (J=5/2) Periodic Anderson Model
Hiroshi Kontani, Kosaku Yamada
Magnetic susceptibility in a heavy fermion systemis composed of the Pauli term (χ_P) and the Van-Vleck term (χ_V). The latter comes from the interband excitation, where f-orbital d…
Theory of Anomalous Hall Effect in a Heavy fermion System with a Strong Anisotropic Crystal Field
Hiroshi Kontani, Morio Miyazawa, Kosaku Yamada
In a heavy fermion system, there exists the anomalous Hall effect caused by localized -orbital freedom, in addition to the normal Hall effect due to the Lorentz force. In 1994,…