相关论文: Integer filling metal insulator transitions in the…
Mott-Hubbard metal-insulator transitions in $N$-fold degenerate Hubbard models are studied within the Gutzwiller approximation. For any rational filling with $x$ (integer) electrons per site it is found that metal-insulator transition…
We study the metal-to-insulator transition of the Hubbard model at zero temperatures in infinite dimensions. The coexistence of metallic and insulating solutions for a finite range of the interaction is established. It is shown that the…
We study the transition from paramagnetic metal to paramagnetic insulator by finite temperature Quantum Monte-Carlo simulations for the 2D Hubbard model at half-filling. Working at the moderately high temperature T=0.33*t where the spin…
A detailed study of electronic phase transitions in the ionic Hubbard model at half filling is presented. Within the dynamical mean field approximation a series of transitions from the band insulator via a metallic state to a Mott-Hubbard…
We investigate paramagnetic metal-insulator transitions in the infinite-dimensional ionic Hubbard model at finite temperatures. By means of the dynamical mean-field theory with an impurity solver of the continuous-time quantum Monte Carlo…
Degenerate Hubbard models are studied using the Generalized-Gutzwiller-Approximation. It is found that the metal-insulator transition occurs at a finite correlation $U_c$ when the average number of electrons per lattice site is an integer.…
Correlated electrons in a binary alloy $A_{x}B_{1-x}$ are investigated within the Hubbard model and dynamical mean--field theory (DMFT). The random energies $\epsilon_{i}$ have a bimodal probability distribution and an energy separation…
We study the Mott transition in Hubbard models with a degenerate band on different 3-dimensional lattices. While for a non-degenerate band only the half-filled system may exhibit a Mott transition, with degeneracy there can be a transition…
A slave boson representation for the degenerate Hubbard model is introduced. The location of the metal to insulator transition that occurs at commensurate densities is shown to depend weakly on the band degeneracy M. The relative weights of…
A systematic study has been made on the metal-insulator (MI) transition of the doubly degenerate Hubbard model (DHM) in the paramagnetic ground state, by using the slave-boson mean-field theory which is equivalent to the Gutzwiller…
We consider the orbitally degenerate 3-band Hubbard model with on-site interactions which favor low spin and low orbital angular momentum using standard second order perturbation theory in the large Hubbard-U limit. At even integer filling…
The Mott-Hubbard metal-insulator transition in the paramagnetic phase of the one-band Hubbard model has long been used to describe similar features in real materials like V$_2$O$_3$. Here we show that this transition is hidden inside a…
The Hubbard model with large orbital degeneracy has recently gained relevance in the context of ultracold earth alkali like atoms. We compute its static properties in the SU(2M) symmetric limit for up to M=8 bands at half filling within…
We investigate the metal-insulator transition in the half-filled Hubbard model on a two-dimensional triangular lattice using both the Kotliar-Ruckenstein slave-boson technique, and exact numerical diagonalization of finite clusters.…
We investigate the metal insulator transitions at finite temperature for the Hubbard model with diagonal alloy disorder. We solve the dynamical mean field theory equations with the non crossing approximation and we use the coherent…
Around a metal-to-insulator transition driven by repulsive interaction (Mott transition) the single particle excitations and the collective excitations are equally important. Here we present results for the generic susceptibilities at zero…
Moir\'e superlattices formed in two-dimensional semiconductor heterobilayers provide a new realization of Hubbard model physics in which the number of electrons per effective atom can be tuned at will. We report on an exact diagonalization…
We investigate the ground-state phase diagram of the one-dimensional "ionic" Hubbard model with an alternating periodic potential at half-filling by numerical diagonalization of finite systems with the Lanczos and density matrix…
The interaction-driven insulator-to-metal transition has been reported in the ionic Hubbard model (IHM) for moderate interaction $U$, while its metallic phase only occupies a narrow region in the phase diagram. To explore the enlargement of…
In the present paper metal-insulator transition is studied in a generalized Hubbard model with correlated hopping at half-filling and zero temperature. Single-particle Green function and energy spectrum of electron system are calculated.…