相关论文: Model-mapped random phase approximation to evaluat…
We study the critical fluctuations near the resistive transition of very thin films of high-temperature cuprate superconductors composed of a number $N$ of only a few unit cells of superconducting bilayers. For that, we solve the…
Magnetic and electronic properties of the Hubbard model on the Bethe and fcc lattices in infinite dimensions have been investigated numerically on the basis of the dynamical coherent potential approximation (CPA) theory combined with the…
From configuration interaction (CI) ab initio calculations, we derive an effective two-orbital extended Hubbard model based on the gerade (g) and ungerade (u) molecular orbitals (MOs) of the charge-transfer molecular conductor (TTM-TTP)I_3…
One-particle spectral properties in the normal phase of the two-dimensional attractive Hubbard model are investigated in the weak coupling regime using the non-selfconsistent T-matrix approximation. The corresponding equations are evaluated…
We perform a first principles band calculation for a group of quasi-two-dimensional organic conductors \beta-(BDA-TTP)2MF6 (M=P, As, Sb, Ta). The ab-initio calculation shows that the density of states (DOS) is correlated with the band width…
Pairing symmetry in $\kappa$-(BEDT-TTF)$_2$X is re-examined by applying fluctuation exchange method to the Hubbard model on the original four band lattice for the first time. Our study is motivated by the discrepancy between a recent…
We compute the two-particle quantities relevant for superconducting correlations in the two-dimensional Hubbard model within the dynamical cluster approximation. In the normal state we identify the parameter regime in density, interaction,…
Superconductivity in the cuprates emerges from an enigmatic metallic state. There remain profound open questions regarding the universality of observed phenomena and the character of precursor fluctuations above the superconducting (SC)…
X-ray absorption spectra on the overdoped high-temperature superconductors Tl_2Ba_2CuO_{6+delta} (Tl-2201) and La_{2-x}Sr_xCuO_{4+delta} (LSCO) reveal a striking departure in the electronic structure from that of the underdoped regime. The…
The two-dimensional Hubbard model exhibits superconductivity with d-wave symmetry even at half-filling in the presence of next-nearest neighbor hopping. Using plaquette cluster dynamical mean-field theory with a continuous-time quantum…
The observed magnetic spin susceptibility of high-temperature superconductors such as La$_{2- x}$Sr$_x$CuO$_4$ increases when $x$ increases from zero, i.e. as one dopes away from half-filling. Recent Monte Carlo simulations of A. Moreo…
It is a distinct possibility that spin fluctuations are the pairing interactions in a wide range of unconventional superconductors. In the case of the high-transition-temperature (high-$T_c$) cuprates, in which superconductivity emerges…
In highly anisotropic cuprate superconductors it is generally accepted that the reversible magnetization vector, M, is essentially perpendicular to the superconducting CuO2 layers in a wide range of crystal orientations with respect to the…
The exchange-driven contribution to the magnetoelectric susceptibility $\hat\alpha$ is formulated using a microscopic model Hamiltonian coupling the spin degrees of freedom to lattice displacements and electric field, which may be…
In non-self-consistent calculations of the total energy within the random-phase approximation (RPA) for electronic correlation, it is necessary to choose a single-particle Hamiltonian whose solutions are used to construct the electronic…
Spin fluctuations have been proposed as a key mechanism for mediating superconductivity, particularly in high-temperature superconducting cuprates, where conventional electron-phonon interactions alone cannot account for the observed…
The emergence of high transition temperature (Tc) superconductivity in strongly correlated materials remains a major unsolved problem in physics. High-Tc materials, such as cuprates, are generally complex and not easily tunable, making…
We investigate the electronic state and the superconductivity in the 5-orbital Hubbard model for iron pnictides by using the dynamical mean-field theory in conjunction with the Eliashberg equation. The renormalization factor exhibits…
The electron-boson spectral density function I^2ChiOmega responsible for carrier scattering of the high temperature superconductor HgBa2CuO4 (Tc = 90 K) is calculated from new data on the optical scattering rate. A maximum entropy technique…
In order to explore how superconductivity arises when charge fluctuations and spin fluctuations coexist, we have obtained a phase diagram against the off-site repulsion V and band filling n for the extended, repulsive Hubbard model on the…