Related papers: Phase Separation and Superconductivity in the Copp…
We use bosonization and renormalization group methods to determine the ground state phase diagram of a one-dimensional frustrated Kondo-Heisenberg system consisting of a one-dimensional spin-1/2 Luttinger liquid coupled by a Kondo exchange…
In complex transition metal oxides (TMO) an arrested electronic phase separation (PS) appears by tuning the system near a Lifshitz transition in multiband Hubbard models. The PS in La2CuO4+y near insulator to metal transition (IMT) is made…
We study theoretically competition between the charge ordering and the superconductivity in two-dimensional organic conductor beta-(meso-DMBEDT-TTF)_2PF_6. We analyze the extended Hubbard model on a weakly-dimerized lattice based on the…
It is argued that a superconducting instability appears in the electronic states on the surface of a topological insulator due purely to electromagnetic interactions. The discussion of this instability is based on the analysis of the…
Experiments on quasi-one-dimensional systems such as quantum wires and metallic chains on surfaces suggest the existence of electron-electron interactions of substantial range and hence physics beyond the Hubbard model. We therefore…
There is growing evidence that the unconventional spatial inhomogeneities in the doped high-Tc superconductors are accompanied by the pairing of electrons, subsequent quantum phase transitions (QPTs), and condensation in coherent states. We…
The three-band model relevant to high temperature copper-oxide superconductors is solved using single-site dynamical mean field theory and a tight-binding parametrization of the copper and oxygen bands. For a band filling of one hole per…
Supersymmetric lattice models of constrained fermions are known to feature exotic phenomena such as superfrustration, with an extensive degeneracy of ground states, the nature of which is however generally unknown. Here we address this…
The quantum dynamics of quasi-one-dimensional ring with varying electron filling factor is investigated in presence of external electric field. The system is modeled within Hubbard Hamiltonian with attractive Coulomb correlation, which…
Phase diagrams of the one-dimensional extended Hubbard model (including nearest-neighbor interaction $V$) at half- and quarter-filling are studied by observing level crossings of excitation spectra using the exact diagonalization. This…
We study correlated two-level quantum dots, coupled in effective 1-channel fashion to metallic leads; with electron interactions including on-level and inter-level Coulomb repulsions, as well as the inter-orbital Hund's rule exchange…
A phase diagram for a quasi-2D metal with variable carrier density has been derived. The phases present are the normal phase, where the order parameter is zero; the pseudogap phase where the absolute value of the order parameter is non-zero…
In this talk I discuss a recently proposed color superconducting phase of asymmetric quark matter where the up and down quark have different chemical potential, being in chemical equilibrium with electrons. Using Schwinger-Dyson equations…
Superconductor-insulator transition driven by the decreasing concentration of electrons $n$ is studied in the case of the disorder potential created by randomly positioned charged impurities. Electrons and Cooper pairs (formed by an…
Copper oxide high temperature superconductors universally exhibit multiple forms of electronically ordered phases that break the native translational symmetry of the CuO2 planes. The interplay between these orders and the superconducting…
We consider the fluctuation conductivity in the critical region of a disorder induced quantum phase transition in layered d-wave superconductors. We specifically address the fluctuation contribution to the system's conductivity in the limit…
The segregation of oxygen in the high critical temperature cuprate superconductor $La_2CuO_{4+y}$ has been systematically studied along the years. In a recent set of experiments, Poccia et al related, for the first time, time ordering ($t$)…
We analyze the combined effect of the long range Coulomb (LRC) interaction and of surface energy on first order density-driven phase transitions in the presence of a compensating rigid background. We study mixed states formed by regions of…
The pairing symmetry in the electron mechanism for superconductivity is explored when charge fluctuations coexist with spin fluctuations. The extended Hubbard model is adopted to obtain, with the fluctuation exchange approximation, a phase…
We study a two-dimensional model of an isolated narrow topological band at partial filling with local attractive interactions. Numerically exact quantum Monte Carlo calculations show that the ground state is a superconductor with a critical…