Related papers: Strong electronic correlations from Hund's couplin…
An instability of the quasi-1D Luttinger liquid associated with the metal - insulator transition is considered. The homogeneous metal ground state of this liquid is demonstrated to be unstable and the charge-density wave arises in the…
We investigate the spin of the ground state of a geometrically confined many-electron system. For atoms, shell structure simplifies this problem-- the spin is prescribed by the well-known Hund's rule. In contrast, quantum dots provide a…
Developing a comprehensive magnetic theory for correlated itinerant magnets poses challenges due to the difficulty in reconciling both local moments and itinerant electrons. In this work, we investigate the microscopic process of magnetic…
Novel phases of two dimensional electron systems resulting from new surface or interface modified electronic structures have generated significant interest in material science. We utilize photoemission spectroscopy to show that the…
Motivated by recent Fermi surface and transport measurements on LaNiO3, we study the Mott Metal-Insulator transitions of perovskite nickelates, with the chemical formula RNiO3, where R is a rare-earth ion. We introduce and study a minimal…
We develop a two-orbital Hubbard model of electron correlations in ultrathin (111)-oriented fcc films of late transition metals such as Co and Ni. Our model indicates that the Mott-Hund's interaction results in ferromagnetic…
We determine the anisotropy of the spin fluctuation induced pairing gap on the Fermi surface of the FeAs based superconductors as function of the exchange and Hund's coupling $J_{H}$. We find that for sufficiently large $J_{H}$, nearly…
Cold atom systems provide a rich platform to realize strongly interacting condensed matter systems, and recent progress in fluorescence imaging technique has enabled identification of nontrivial doublon, singlon, and holon correlation…
Correlation effects are observed strong in Iron chalcogenides superconductors by experimental and theoretical investigations. We present a comparative study of the influence of Coulomb interaction and Hund's coupling in the electronic…
High temperature superconductivity was achieved by introducing holes in a parent compound consisting of copper oxide layers separated by spacer layers. It is possible to dope some of the parent compounds with electrons, and their physical…
Metal to insulator transitions (MITs) driven by strong electronic correlations are common in condensed matter systems, and are associated with some of the most remarkable collective phenomena in solids, including superconductivity and…
We investigate the influence of an unoccupied band on the transport properties of a strongly correlated electron system. For that purpose, additional orbitals are coupled to a Hubbard model via hybridization. The filling is one electron per…
The effect of the strong intersite Coulomb correlations on the formation of the electron structure of the t-V-model has been studied. A qualitatively new result has been obtained which consists in the occurrence of a split-off band of the…
Electronic structure of strongly correlated transition metal oxides (TMOs) is a complex phenomenon due to competing interaction among the charge, spin, orbital and lattice degrees of freedom. Often individual compounds are examined to…
We present the influence of spin correlation on the metal-insulator transitions (MIT) in two-orbital Hubbard models by the Kotliar-Ruckenstein slave-boson approach. In the asymmetric half-filling situation, the two orbits simultaneously…
Analysis of higher-order correlation functions has become a powerful tool for investigating interacting many-body systems in quantum simulators, such as quantum gas microscopes. Experimental measurements of mixed spin-charge correlation…
We consider circular and elliptic quantum dots with parabolic external confinement, containing 0 - 22 electrons and with values of r_s in the range 0 < r_s < 3. We perform restricted and unrestricted Hartree-Fock calculations, and further…
The superconducting phase in iron based high Tc superconductors (FeSC) as in other unconventional superconductors such as the cuprates neighbours a magnetically ordered one in the phase diagram. This proximity hints at the importance of…
We study the interplay between strong electron-electron and electron-phonon interactions within a two-orbital molecule coupled to metallic leads, taking into account Holstein-like coupling of a local phonon mode to the molecular charge as…
The importance of Hund's rule coupling for the stabilization of itinerant ferromagnetism is investigated within a two-band Hubbard model. The magnetic phase diagram is calculated by finite-temperature quantum Monte Carlo simulations within…