相关论文: Hybridisation in two-band Hubbard models with diff…
We show that the Mott transition occurring in bosonic Hubbard models can be successfully described by a simple variational wave function that contains all important long-wavelength correlations. Within this approach, a smooth…
Mott transitions in the two-orbital Hubbard model with different bandwidths are investigated at finite temperatures. By means of the self-energy functional approach, we discuss the stability of the intermediate phase with one orbital…
We study the effects of interorbital hopping on orbital fluctuations and Mott-Hubbard metal-insulator transition (MIT) in the two-orbital Hubbard model within the extended linearized dynamical mean-field theory. By mapping the model onto an…
Using the generalized Gutzwiller method we present results on the ferromagnetic behavior of extended Hubbard models with two degenerate eg orbitals. We find significant differences to results obtained from Hartree-Fock theory.
We investigate the Mott transitions in the multi-orbital Hubbard model at half-filling by means of the self-energy functional approach. The phase diagrams are obtained at finite temperatures for the Hubbard model with up to four-fold…
Orbital differentiation is a common theme in multiorbital systems, yet a complete understanding of it is still missing. Here, we consider a minimal model for orbital differentiation in Hund metals with a highly accurate method: We use the…
Elucidating the physics of the single-orbital Hubbard model in its intermediate coupling regime is a key missing ingredient to our understanding of metal-insulator transitions in real materials. Using recent non-perturbative many-body…
We study the Mott-insulator transition of bosonic atoms in optical lattices. Using perturbation theory, we analyze the deviations from the mean-field Gutzwiller ansatz, which become appreciable for intermediate values of the ratio between…
In a system where selective Mott localization is realized, some electrons show a gap to charge excitations while others do not. A hybridization between these two kind of electrons will lead to a smoothening of this sharp difference and can…
We explore the ground-state properties of the two-band Hubbard model with degenerate electronic bands, parametrized by nearest-neighbor hopping $t$, intra- and inter-orbital on-site Coulomb repulsions $U$ and $U^\prime$, and Hund coupling…
We use the Gutzwiller variational many-body theory to investigate the stability of orbitally ordered states in a two-band Hubbard-model without spin degrees of freedom. Our results differ significantly from earlier Hartree-Fock calculations…
We found direct experimental evidence for an orbital switching in the V 3d states across the metal-insulator transition in VO$_{2}$. We have used soft-x-ray absorption spectroscopy at the V $L_{2,3}$ edges as a sensitive local probe, and…
A generalized version of the fidelity susceptibility of single-band and multi-orbital Hubbard models is systematically studied using single-site dynamical mean-field theory in combination with a hybridization expansion continuous-time…
At the Mott transition, electron-electron interaction changes a metal, in which electrons are itinerant, to an insulator, in which electrons are localized. This phenomenon is central to quantum materials. Here we contribute to its…
We examine finite-temperature phase transitions in the two-orbital Hubbard model with different bandwidths by means of the dynamical mean-field theory combined with the continuous-time quantum Monte Carlo method. It is found that there…
The effect of interorbital hopping on the orbital selective Mottness in a two-band correlation system is investigated by using the dynamical mean-field theory with the Lanczos method as impurity solver. We construct the phase diagram of the…
Interaction-driven metal-insulator transitions or Mott transitions are widely observed in condensed-matter systems. In multi-orbital systems, many-body physics is richer in which an orbital-selective metal-insulator transition is an…
We investigate nonmagnetic metal-insulator transition in the 1/5-depleted square lattice Hubbard model at half-filling within the 8-site cellular dynamical mean field theory. We find that a metal-insulator transition without any signatures…
We analyze the electronic properties of interacting crystal field split three band systems. Using a rotationally invariant slave boson approach we analyze the behavior of the electronic mass renormalization as a function of the intralevel…
Two very different methods -- exact diagonalization on finite chains and a variational method -- are used to study the possibility of a metal-insulator transition in the symmetric half-filled periodic Anderson-Hubbard model. With this aim…