Related papers: Exact diagonalization study of optical conductivit…
We apply self-consistent second order perturbation theory (SCSOPT) with respect to the on-site repulsive interaction U to study the Hubbard model in two dimensions. We investigate single particle properties of the model over the entire…
We investigate the optical conductivity of half-filled N-leg Hubbard ladders far into the ``deconfinement'' limit (i.e., weak Hubbard interaction and relatively strong interchain hopping). The N-leg Hubbard ladder is equivalent to an N-band…
Hubbard model is an important model in theory of strongly correlated electron systems. In this contribution we introduce this model along with numerically exact method of diagonalization of the model.
We perform a detailed study of the phase transitions and mechanisms of electron localization in the extended Hubbard model using the dynamical cluster approximation on a $2\times 2$ cluster. We explore the interplay of charge order and Mott…
The two-orbital Hubbard model for the pnictides is studied numerically using the real-space Hartree-Fock approximation on finite clusters. Upon electron doping, states with a nonuniform distribution of charge are stabilized. The observed…
Many strongly correlated systems exhibit strange metallic behavior in certain parameter regimes characterized by anomalous transport properties that are irreconcilable with a Fermi-liquid-like description in terms of quasiparticles. The…
We extend previous studies on orbital-selective Mott transitions in the paramagnetic state of the half-filled degenerate two-band Hubbard model to the general doped case, using a high-precision quantum Monte Carlo dynamical mean-field…
We study the three-band Hubbard model for the copper oxide plane of the high-temperature superconducting cuprates using determinant quantum Monte Carlo and the dynamical cluster approximation (DCA) and provide a comprehensive view of the…
The formation of stripes in six-leg Hubbard ladders with cylindrical boundary conditions is investigated for two different hole dopings, where the amplitude of the hole density modulation is determined in the limits of vanishing DMRG…
Binding energies of negative and positive trions in doped GaAs quantum wells in high magnetic fields are studied by exact numerical diagonalization in spherical geometry. Compared to earlier calculations, finite width of the quantum well…
We study the frequency dependence of the optical conductivity $\text{Re} \, \sigma(\omega)$ of the Heisenberg spin-$1/2$ chain in the thermal and near the transition to the many-body localized phase induced by the strength of a random…
We present a large scale exact diagonalization study of the one dimensional spin $1/2$ Heisenberg model in a random magnetic field. In order to access properties at varying energy densities across the entire spectrum for system sizes up to…
The dispersion relation of a doped hole in the half-filled 2D Hubbard model is shown to follow a k^4 law around the (0,pi) and (pi,0) points in the Brillouin zone. Upon addition of pair-hopping processes this dispersion relation is unstable…
We report electronic Raman scattering measurements on Bi$_2$Sr$_2$(Y$_{1-x}$Ca$_x$)Cu$_2$O$_{8+\delta}$ single crystals at different doping levels. The dependence of the spectra on doping and on incoming photon energy is analyzed for…
The study of entanglement in strongly correlated electron systems typically requires knowledge of the reduced density matrix. Here, we apply the parquet dynamical vertex approximation to study the two-site reduced density matrix at varying…
Cooperation and competition between the antiferromagnetic, d-wave superconducting and Mott-insulating states are explored for the two-dimensional Hubbard model including nearest and next-nearest-neighbor hoppings at zero temperature. Using…
A model to describe electronic correlations in energy bands is considered. The model is a generalization of the conventional Hubbard model that allows for the fact that the wavefunction for two electrons occupying the same Wannier orbital…
The one-dimensional Hubbard model is investigated by means of two different cluster schemes suited to introduce short-range spatial correlations beyond the single-site Dynamical Mean-Field Theory, namely the Cluster-Dynamical Mean-Field…
We present an exact diagonalization study of the self-energy of the two-dimensional Hubbard model. To increase the range of available cluster sizes we use a corrected t-J model to compute approximate Greens functions for the Hubbard model.…
Heavy carbon doping of MgB$_2$ is studied by first principles electronic structure studies of two types, an ordered supercell (Mg(B$_{1-x}$C$_{x}$)$_{2}$,x=0.0833) and also the coherent potential approximation method that incorporates…