48 citations · 188 across the 15 of their papers we have counts for
6 papers · 1 filter
Coexistence of - and -wave gaps due to pair-hopping and exchange interactions
Shigeru Koikegami
I investigate the superconductivity of the three-band -- model derived from the three-band Hubbard model using the Schrieffer-Wolff transformation. My model is designed co…
Three-Dimensional Multiband d-p Model of Superconductivity in Spin-Chain Ladder Cuprate
Shigeru Koikegami, Takashi Yanagisawa
We study the superconductivity in the three-dimensional multiband d-p model, in which a CuO-ladder layer and a CuO-chain layer are alternately stacked, as a model of th…
Superconductivity in Multilayer Perovskite: Weak Coupling Analysis
Shigeru Koikegami, Takashi Yanagisawa
We investigate the superconductivity of a three-dimensional d-p model with a multilayer perovskite structure on the basis of the second-order perturabation theory within the weak c…
Superconductivity in SrRuO Mediated by Coulomb Scattering
Shigeru Koikegami, Yoshiyuki Yoshida, Takashi Yanagisawa
We investigate the superconductivity in SrRuO on the basis of the three-dimensional three-band Hubbard model. We propose a model with Coulomb interactions among the electro…
Theoretical Description of Nearly Discontinuous Transition in Superconductors with Paramagnetic Depairing
Hiroto Adachi, Shigeru Koikegami, Ryusuke Ikeda
Based on a theoretical argument and Monte Carlo simulations of a Ginzburg-Landau model derived microscopically, it is argued that, in type-II superconductors where {\it both} the p…
Anisotropic Optical Conductivity of Nd2-xCexCuO4 Thin Films
Takashi Yanagisawa, Shigeru Koikegami, Hajime Shibata +5
Opticcal conductivity spectra of Nd2-xCexCuO4 thin films, measured by the reflectance-transmittance method (R-T method) which has been proposed to investigate far-infrared…