Related papers: One particle interchain hopping in coupled Hubbard…
The dynamical density-matrix renormalization group technique is used to calculate spin and charge excitation spectra in the one-dimensional (1D) Hubbard model at quarter filling with nearest-neighbor $t$ and next-nearest-neighbor $t'$…
Particle-hole instabilities are studied within a two dimensional model of fermions interacting with antiferromagnetic spin fluctuations (spin-fermion model). In contrast to previous works, we assume that neighboring hot spots overlap due to…
Using a controlled analytic non-perturbative treatment, that accounts for the quantum nature of the phonons, we derive a model that generically describes cooperative breathing-mode at strong electron-phonon interaction in one-band…
We consider the extended Hubbard diamond chain with an arbitrary number of particles driven by chemical potential. The interaction between dimer diamond chain and nodal couplings is considered in the atomic limit (no hopping), while the…
We investigate the Hall effect in two different theoretical models of strongly correlated systems: a system made of weakly coupled Luttinger liquids, in the presence of umklapp scattering, and the 2D triangular lattice, with…
In order to explore why the multi-layered cuprates have such high Tc's, we have examined various inter-layer processes. Since the inter-layer one-electron hopping has little effects on the band structure, we turn to the inter-layer pair…
We find a strongly enhanced entanglement within the pseudogap regime of the Hubbard model. This entanglement is estimated from the quantum Fisher information and, avoiding the ill-conditioned analytical continuation, the quantum variance.…
We study the Hubbard model on a square lattice, using the dynamical vertex approximation and the parquet approximation. These methods allow us to describe the mutual interference of spin-fluctuations in the particle-hole channel and…
We investigate the spin/charge transport in a one-dimensional strongly correlated system by using the adaptive time-dependent density-matrix renormalization group method. The model we consider is a non-half-filled Hubbard chain with a bond…
The interactions between holes in the Hubbard model, in the low density, intermediate to strong coupling limit, are investigated. Dressed spin polarons in neighboring sites have an increased kinetic energy and an enhanced hopping rate. Both…
Transport through a Hubbard chain of size N (=1,2,3,...) connected to reservoirs is studied at T = 0 in an electron-hole symmetric case based on the second-order perturbation theory in U. The result shows a typical even-odd property…
We analyze the behavior of the dynamic scattering amplitude between Fermi liquid quasiparticles at the Fermi surface in the proximity of a charge instability, which may occur in the high temperature superconducting cuprates. Within the…
We study the frequency and space dependence of the local tunneling density of states of a Luttinger liquid (LL) which is connected to a superconductor. This coupling {\em strongly} modifies the single-particle properties of the LL. It…
A quantum Monte Carlo simulation method has been developed and applied to study the critical behavior of a single Kondo impurity in a Luttinger liquid. This numerically exact method has no finite-size limitations and allows to simulate the…
We study a multi-orbital Hubbard--Su-Schrieffer-Heeger model for the one-dimensional (1D) corner-shared cuprates in the adiabatic and nonadiabatic limits using the exact diagonalization and determinant quantum Monte Carlo methods. Our…
We review some recent progresses in study of the 1D strongly correlated electron systems of long range hopping and exchange. The systems are completely integrable, with infinite number of constants of motions. The results of the physical…
Using dynamical-mean-field theory for clusters, we study the two-dimensional Hubbard model in which electrons are coupled with the orthorhombic lattice distortions through the modulation in the hopping matrix. Instability towards…
We study a multi-band Hubbard model in its orbital selective Mott phase, in which localized electrons in a narrow band coexist with itinerant electrons in a wide band. The low-energy physics of this phase is shown to be closely related to…
We study the electronic structure of the doped paramagnetic insulator by finite temperature Quantum Monte-Carlo simulations for the 2D Hubbard model. Throughout we use the moderately high temperature T=0.33t, where the spin correlation…
Full or empty narrow bands near the Fermi level are known to enhance superconductivity by promoting scattering processes and spin fluctuations. Here, we demonstrate that doublon-holon fluctuations in systems with half-filled narrow bands…