Related papers: Assisted hopping and interaction effects in impuri…
A generalized Anderson model for a magnetic impurity in an interacting one-dimensional electron gas is studied via a mapping onto a classical Coulomb gas. For weak potential scattering, the local-moment parameter regime expands as repulsive…
We investigate a multi-orbital extension of the periodic Anderson model with particular emphasis on electron correlations including orbital fluctuations. By means of a linearized version of the dynamical mean-field theory, we compute the…
We consider long-range correlated disorder and mutual interacting particles according to a dipole-dipole coupling as modifications to the one-dimensional Anderson model. Technically we rely on the (numerical) exact diagonalization of the…
We study two coupled 3D lattices, one of them featuring uncorrelated on-site disorder and the other one being fully ordered, and analyze how the interlattice hopping affects the localization-delocalization transition of the former and how…
In the present paper we study some correlation effects in a generalized Hubbard model with correlated hopping within low-temperature region using a generalized mean-field approximation. It is shown that in a series of cases the model leads…
The interactions between holes in the Hubbard model, in the low density, intermediate to strong coupling limit, are investigated by systematically improving mean field calculations. The Configuration Interaction basis set is constructed by…
We illustrate the renormalized perturbation expansion method by applying it to a single impurity Anderson model. Previously, we have shown that this approach gives the {\it exact} leading order results for the specific heat, spin and charge…
We present selected results from combined analytical and numerical studies of the Anderson-impurity model within the framework of infinite order perturbation theory with respect to the hybridization. Our approximation goes considerably…
Anderson localization is a paradigmatic coherence effect in disordered systems, often analyzed in the absence of dissipation. Here we consider the case of coherent dissipation, occurring for open system with coupling to a common decay…
We study the effects of assisted tunneling or correlated hopping between next nearest neighbours in a two species Bose-Hubbard system. The system is the bosonic analong of the fermionic system studied in Phys. Rev. Lett. {\bf 116}, 225303…
We perform time-resolved exact diagonalization of the Hubbard model with time dependent hoppings on small clusters of up to $12$ sites. Here, the time dependence originates from a classic electromagnetic pulse, which mimics the impact of a…
We apply the functional renormalization group method to the calculation of dynamical properties of zero-dimensional interacting quantum systems. As case studies we discuss the anharmonic oscillator and the single impurity Anderson model. We…
We use the numerical renormalization group method to study an Anderson impurity in a conduction band with the density of states varying as rho(omega) \propto |omega|^r with r>0. We find two different fixed points: a local-moment fixed point…
A new theoretical model is presented to study the nanoscale electronic inhomogeneity in high-$T_c$ cuprates. In this model, we argue that the randomly distributed out-of-plane interstitial oxygen dopants induces locally the off-diagonal…
A one-dimensional system of masses with nearest-neighbor interactions and periodic boundary conditions is used to study mode decay and ergodicity in nonlinear, disordered systems. The system is given an initial periodic displacement, and…
We study the ground state phase diagram of the Anderson-Hubbard model with correlated hopping at half filling in one-dimension. The Hamiltonian has a local Coulomb repulsion $U$ and a disorder potential with local energies randomly…
We study the effects of partial correlations in kinetic hopping terms of long-range disordered random matrix models on their localization properties. We consider a set of models interpolating between fully-localized Richardson's model and…
We study the interplay between electron correlation and disorder in the two-dimensional Hubbard model at half-filling by means of a variational wave function that can interpolate between Anderson and Mott insulators. We give a detailed…
We study the interacting, symmetrically coupled single impurity Anderson model. By employing the nonequilibrium Green's function formalism, we establish an exact relationship between the steady-state charge current flowing through the…
Anderson localization is known to be inevitable in one dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess "additional" integrals of motion as well, so…