Related papers: Extended Hubbard model on a C$_{20}$ molecule
Motivated by significant discrepancies between experimental observations of electron-doped cuprates and numerical results of the Hubbard model, we investigate the role of nearest-neighbor (NN) electron interactions $V$ by studying the…
A necessary condition for superconductivity (SC) driven by electron correlations is that electron-electron (e-e) interactions enhance superconducting pair-pair correlations, relative to the noninteracting limit. We report high-precision…
We compute high-resolution angle-resolved photoemission spectroscopy of the Hubbard model using the unbiased determinant quantum Monte Carlo algorithm, revealing an asymmetry between electron and hole doping. Electron doping exhibits more…
We investigate the strong correlation effect in the spinless electron-hole two-band Hubbard model using the dynamical mean-field theory. At half filling, both the renormalization factor $Z$ and the number of conduction electrons (valence…
The Hubbard model on a cube was revisited and extended by both nearest-neighbor (nn) Coulomb correlation and {nearest-neighbor} Heisenberg exchange. The complete eigensystem was computed exactly for all electron occupancies and all model…
Strong electron correlations lie at the origin of transformative phenomena such as colossal magneto-resistance and high-temperature superconductivity. Already near room temperature, doped copper oxide materials display remarkable features…
We study the weak-coupling limit of the $t-t^\prime-U$ Hubbard model on a two-dimensional square lattice using a direct perturbative approach. Aided by symbolic computational tools, we compute the longitudinal density-density correlation…
By using the constrained-phase quantum Monte Carlo method, we performed a systematic study of the pairing correlations in the ground state of the doped Kane-Mele-Hubbard model on a honeycomb lattice. We find that pairing correlations with…
We investigate the momentum-resolved spin and charge susceptibilities, as well as the chemical potential and double occupancy in the two-dimensional Hubbard model as functions of doping, temperature and interaction strength. Through these…
We study the pairing within the Peierls-Hubbard Model for electron- and hole-doped analogs of C$_{60}$ accessible to exact diagonalization techniques (cube, truncated tetrahedron, {\it etc.}). We discuss how inclusion of electron-phonon…
In this paper we examine the effects of electron-hole asymmetry as a consequence of strong correlations on the electronic Raman scattering in the normal state of copper oxide high temperature superconductors. Using determinant quantum Monte…
We show that the charge transfer excitons in a Hubbard model system including nearest neighbor Coulomb interactions effectively attain some charge in doped systems and become visible in photoelectron and inverse photoelectron…
The ground-state properties of C$_{20}$ fullerene clusters are determined in the framework of the Hubbard model by using lattice density-functional theory (LDFT) and scaling approximations to the interaction-energy functional. Results are…
In this study we have computed the pair correlation functions in the two-dimensional Hubbard model using a quantum Monte Carlo method. We employ a new diagonalization algorithm in quantum Monte Carlo method which is free from the negative…
The puzzling electronic correlation effects in the sodium cobaltate system are studied by means of the combination of density functional theory and the rotationally invariant slave boson (RISB) method in a cellular-cluster approach.…
We explore the two-dimensional extended Hubbard model on the triangular lattice in the high doping regime. On-site and nearest-neighbour repulsive interactions are treated in a non-perturbative way by means of Extended Dynamical Mean Field…
We studied the effects of hole doping on spin correlations in the periodic Anderson model, mainly at the full and three-quarters-full lower bands cases. In the full lower band case, strong anti-ferromagnetic correlations develop when the…
Superconducting, magnetic, and charge correlation functions and dynamic spin correlation functions of the doped two-chain Hubbard model is studied with the projector Quantum Monte carlo method and Lanczos recursion method. Of the three…
Determining the ground state properties of the two-dimensional Hubbard model has remained an outstanding problem. Applying recent advances in constrained path auxiliary-field quantum Monte Carlo techniques and simulating large rectangular…
We present a numerical study of the doping dependence of the spectral function of the n-type cuprates. Using a variational cluster-perturbation theory approach based upon the self-energy-functional theory, the spectral function of the…