62 citations · 123 across the 6 of their papers we have counts for
8 papers · 1 filter
Successive Phase Transitions in Na_{0.5}CoO_{2} based on the Triangular Lattice d-p Model
Youichi Yamakawa, Yoshiaki Ōno
We investigate the electronic states of the CoO_2 plane in the layered cobalt oxides Na_{0.5}CoO_{2} using the realistic 11 band d-p model on a two-dimensional triangular lattice.…
Magnetism and Superconductivity in the Two-Dimensional 16 Band d-p Model for Iron-Based Superconductors
Yuki Yanagi, Youichi Yamakawa, Yoshiaki Ōno
The electronic states of the Fe2As2 plane in iron-based superconductors are investigated on the basis of the two-dimensional 16-band d-p model which includes the Coulomb interactio…
Phonon softening and double-well potential formation due to electron-phonon interaction in heavy-fermion systems
Keisuke Mitsumoto, Yoshiaki Ono
We investigate the periodic Anderson-Holstein model by using the dynamical mean-field theory combined with the exact diagonalization method. For the strong electron-phonon coupling…
Phase diagram and dynamic response functions of the Holstein-Hubbard model
W. Koller, D. Meyer, A. C. Hewson +1
We present the phase diagram and dynamical correlation functions for the Holstein-Hubbard model at half filling and at zero temperature. The calculations are based on the Dynamical…
Combined Analysis of Numerical Diagonalization and Renormalization Group methods for the One-Dimensional - Model at Quarter filling
Kazuhiro Sano, Yoshiaki Ono
The one-dimensional extended Hubbard model with both the on-site and the nearest neighbor interactions at quarter filling is studied by using a novel finite size scaling. W…
Nonlinear Sigma model method for the J1-J2 Heisenberg model: disordered ground state with plaquette symmetry
Ken'ichi Takano, Yoshiya Kito, Yoshiaki Ono +1
A novel nonlinear sigma model method is proposed for the two-dimensional J1-J2 model, which is extended to include plaquette-type distortion. The nonlinear sigma model is properly…