Related papers: Hybridizing localized and itinerant electrons: a r…
We examine the orbital-selective Mott transition in the non-hybridized two-band Hubbard model using the dynamical mean-field theory. We find that the orbital-selective Mott transition could be quantitatively depicted by the {local two-qubit…
Unveiling the nature of the pseudogap and its relation to both superconductivity and antiferromagnetic Mott insulators, the pairing mechanism, and a non-Fermi liquid phase is a key issue for understanding high temperature superconductivity…
A phenomenological model with itinerant bands and local states trapped by the lattice on the Cu-sites, is discussed to describe global features of cuprates. Relative energy positions of localized and itinerant states being tuned…
We outline a partial-fractions decomposition method for determining the one-particle spectral function and single-particle density of states of a correlated electronic system on a finite lattice in the non self-consistent T-matrix…
We study the evolution of a Mott-Hubbard insulator into a correlated metal upon doping in the two-dimensional Hubbard model using the Cellular Dynamical Mean Field Theory. Short-range spin correlations create two additional bands apart from…
We investigate the orbital selective Mott transition in two-band Hubbard models by means of the Gutzwiller variational theory. In particular, we study the influence of a finite local hybridisation between electrons in different orbitals on…
We study pseudogap phenomena and Fermi-arc formation experimentally observed in typical two dimensional doped Mott insulators, namely, underdoped cuprate superconductors. To develop a physically unequivocal theory, we start from the…
Hund coupling in the degenerate five-band Hubbard model near n=6 occupancy is shown to give rise to a significant depletion of spectral weight above the Fermi level. Calculations within dynamical mean field theory combined with exact…
The Roth's two-pole approximation has been used by the present authors to study the effects of the hybridization in the superconducting properties of a strongly correlated electron system. The model used is the extended Hubbard model which…
Correlated electron systems may give rise to multiple effective interactions whose combined impact on quasiparticle properties can be difficult to disentangle. We introduce an unambiguous decomposition of the electronic self-energy which…
Pseudogap formation is an ubiquitous phenomena in strongly-correlated superconductors, for example cuprates, heavy-fermion superconductors, and iron pnictides. As the system is cooled, an energy gap opens in the excitation spectrum before…
Superconducting mechanism of cuprates is discussed in the light of the proximity of the Mott insulator. The proximity accompanied by suppression of coherence takes place in an inhomogeneous way in the momentum space in finite-dimensional…
The two-orbital degenerate Hubbard model with distinct hopping integrals is studied by combining dynamical mean-field theory with quantum Monte Carlo simulations. The role of orbital fluctuations for the nature of the Mott transition is…
The mechanism of the pseudogap observed in hole-doped cuprates remains one of the central puzzles in condensed matter physics. We analyze this phenomenon via a Feynman-diagrammatic inspection of the Hubbard model. Our approach captures the…
Superconductivity in cuprates is achieved by doping holes into a correlated charge-transfer insulator. While the correlated character of the parent insulator is now understood, there is no accepted theory for the "normal" state of the doped…
We calculate the one-electron Green's function of the 2D attractive Hubbard model by coupling the electrons to pair fluctuations. The latter are approximated by homogeneous amplitude fluctuations and phase correlations corresponding to the…
When holes move in the background of strong antiferromagnetic correlation, two effects with different spatial scale emerge, leading to a much reduced hopping integral with an additional phase factor. An effective Hamiltonian is then…
It is widely believed that high-temperature superconductivity in the cuprates emerges from doped Mott insulators. The physics of the parent state seems deceivingly simple: The hopping of the electrons from site to site is prohibited because…
Results for pseudogaps are obtained from a band model, where the stability of the gap depends on the amplitudes of vibrational displacements, or magnetic moments, and their coupling to electrons. A one-particle gap is favored by normal…
We study how the electron hopping reduces the Mott-Hubbard band gap in the limit of a large Coulomb interaction U and as a function of the orbital degeneracy N. The results support the conclusion that the hopping contribution grows as…