This article reviews quantum cluster theories, a set of approximations for infinite lattice
models which treat correlations within the cluster explicitly, and correlations at longer length …

In order to discuss superconductivity in orbital degenerate systems, a microscopic
Hamiltonian is introduced. Based on the degenerate model, a strong-coupling theory of …

We present a simple implementation of the dynamical mean-field-theory approach to the
electronic structure of strongly correlated materials. This implementation achieves full self …

We present single-particle and thermodynamic properties of the half-filled single-band
Hubbard model in 2D calculated in the self-consistent fluctuation exchange approximation …

Magnetic interactions in ionic solids are studied using parameter-free methods designed to
provide accurate energy differences associated with quantum states defining the …

We present a method to considerably improve the numerical performance for solving
Eliashberg-type coupled equations on the imaginary axis. Instead of the standard practice of …

Motivated by recent experimental measurements, we study the quasiparticle spectra and the
collective excitations in doped Sr 2 IrO 4, in which the interesting interplay between the …

We report a superconducting transition in the fully conserving fluctuation exchange
approximation for a two-dimensional attractive Hubbard model. The transition temperature …

The electron‐transfer matrix element Vab, has been computed by using density functional
theory and a configuration interaction procedure for some case examples. These examples …

The ab initio cluster model approach has been used to study the electronic structure and
magnetic coupling of KCuF 3 and K 2 CuF 4 in their various ordered polytype crystal forms …