Related papers: On the Liaison Between Superconductivity and Phase…
The conductance through a semi-infinite one-dimensional wire, partly embedded in a superconducting bulk electrode, is studied. When the electron-electron interactions within the wire are strongly repulsive, the wire effectively decouples…
Cuprates exhibit exceptionally strong superconductivity. To understand why, it is essential to elucidate the nature of the electronic interactions that cause pairing. Superconductivity occurs on the backdrop of several underlying electronic…
The two-band Hubbard model is used to analyze a possibility of a non-uniform charge distribution in a strongly correlated electron system with two types of charge carriers. It is demonstrated that in the limit of strong on-site Coulomb…
We study the square-lattice extended Hubbard model with on-site $U$ and nearest-neighbor $V$ interactions by exact diagonalization. We show that non-equilibrium quench dynamics can help determine the equilibrium phase transition boundaries,…
Pair spin-orbit interaction can emerge in strongly-interacting systems characterized by a large spin-orbit coupling. Here we study the role of this interaction in stabilizing ordered and unconventional superconducting phases. We find that,…
A model is proposed such that quasi-particles (electrons or holes) residing in the CuO2 planes of cuprates may interact leading to metallic or superconducting behaviors. The metallic phase is obtained when the quasi-particles are treated as…
We investigate the density instabilities present in the infinite-U Hubbard-Holstein model both at zero and finite momenta as well as the occurrence of Cooper instabilities with a specific emphasis on the role of long-range Coulomb forces.…
Many theoretical approaches find d-wave superconductivity in the prototypical one-band Hubbard model for high-temperature superconductors. At strong-coupling (U > W, where U is the on-site repulsion and W=8t the bandwidth) pairing is…
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…
We have made a variational analysis on an evolution of superconductivity from weak to strong coupling regime. In contrast to a crossover without thermodynamic anomaly found in a dilute system, we show the existence of a quantum phase…
We study the phase diagrams and thermodynamic properties of a system of coexisting itinerant electrons and local pairs (LP), in the presence of diagonal disorder. The model considered takes into account both the charge exchange couplings,…
Properties of superfluid states of two-dimensional electron systems with critical antiferromagnetic fluctuations are investigated. These correlations are found to result in the emergence of rapidly varying in the momentum space terms in all…
We study the competing charge-density-wave and superconducting order in the attractive Hubbard model under a voltage bias, using steady-state non-equilibrium dynamical mean-field theory. We show that the charge-density-wave is suppressed in…
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…
Understanding competing instabilities in systems with correlated fermions remains one of the holy grails of modern condensed matter physics. Among the fermionic lattice models used to this effect, the extended Hubbard model occupies a prime…
We investigate the symmetry of the superconducting order parameter in the proximity of a phase-separation or of an incommensurate charge-density-wave instability. The attractive effective interaction at small or intermediate transferred…
Understanding the electron pairing in hole-doped cuprate superconductors has been a challenge, in particular because the "normal" state from which it evolves is unprecedented. Now, after three and a half decades of research, involving a…
We use a variational approach to gain insight into the strongly correlated d-wave superconducting state of the high Tc cuprates at T=0. We show that strong correlations lead to qualitatively different trends in pairing and phase coherence:…
By using variational wave functions and quantum Monte Carlo techniques, we investigate the interplay between electron-electron and electron-phonon interactions in the two-dimensional Hubbard-Holstein model. Here, the ground-state phase…
To understand the interplay of d-wave superconductivity and antiferromagnetism in the cuprates, we consider a two-dimensional extended Hubbard model with nearest neighbor attractive interaction. Free energy of the homogeneous (coexisting…