Related papers: Band-structure effects on superconductivity in Hub…
We study vortex structure in a two-band superconductor, in which one band is ballistic and quasi-two-dimensional (2D), and the other is diffusive and three-dimensional (3D). A circular cell approximation of the vortex lattice within the…
Recently it has been demonstrated that the pair-exchange coupling of quasi-one-dimensional (Q1D) bands with conventional higher-dimensional bands in one multiband superconducting material can result in the formation of robust aggregate pair…
We present a detailed description of two-band quasi-2D metals with s-wave superconducting (SC) and antiferromagnetic spin-density wave (SDW) correlations. We present a general approach and use it to investigate the influence of the…
We study correlation effects in a three-band extended Hubbard model of Cu -- O planes within the 1/N mean field approach, in the infinite U limit. We investigate the emerging phase diagram and discuss the low energy scales associated with…
Resonances in the superconducting properties, in a regime of crossover from BCS to mixed Bose-Fermi superconductivity, are investigated in a two-band superconductor where the chemical potential is tuned near the band edge of the second…
In this letter, we have studied the effects of proximity of a superconductor to a normal metal. The system, represented by a bilayer attractive Hubbard model, is investigated using layer-dynamical mean field theory and iterated perturbation…
Superconductivity of quasi-one-dimensional organic conductors with a quarter-filled band is investigated using the two-loop renormalization group approach to the extended Hubbard model for which both the single electron hopping t_{\perp}…
The transition mechanism in high temperature cuprate superconductors is an outstanding puzzle. A previous suggestion on the role of non-linear local lattice instability modes on the microscopic pairing mechanism in high temperature cuprate…
We investigate the optical conductivity of half-filled N-leg Hubbard ladders far into the ``deconfinement'' limit (i.e., weak Hubbard interaction and relatively strong interchain hopping). The N-leg Hubbard ladder is equivalent to an N-band…
Surfaces of $d$-wave superconductors may host a substantial density of zero-energy Andreev states. The zero-energy flat band appears due to a topological constraint, but comes with a cost in free energy. We have recently found that an…
Using a renormalization group approach, we determine the phase diagram of an extended quasi-one-dimensional electron gas model that includes interchain hopping, nesting deviations and both intrachain and interchain repulsive interactions.…
The extended Hubbard model can host s-wave, d-wave and p-wave superconducting phases depending on the values of the on-site and nearest-neighbour interactions. Upon detailed examination of the free energy functional of the gap in this…
Recent experiments have revealed the substantial impact of broken rotational symmetry on the superconductivity. In the pursuit of understanding the role played by this symmetry breaking particularly in cuprate and nickelate superconductors…
Interplay between antiferromagnetism and superconductivity is studied by using the 3-dimensional nearly half-filled Hubbard model with anisotropic transfer matrices $t_{\rm z}$ and $t_{\perp}$. The phase diagrams are calculated for varying…
The power-law temperature dependences of the specific heat, the nuclear relaxation rate, and the thermal conductivity suggest the presence of line nodes in the superconducting gap of Sr2RuO4. These recent experimental observations…
We report on the result of quantum Monte Carlo simulation of quasi-one-dimensional electron systems at 1/4-filling, considering organic superconductors such as TMTSF- and TMTTF-salts. We focus on the effect of dimensionality (interchain…
We explore how the superconductivity arising from the on-site electron-electron repulsion will change when the repulsion is changed to a long-ranged, 1/r-like one by introducing an extended Hubbard model with the repulsion extending to…
Magnetic-field-angle-resolved heat capacity of dimer-Mott organic superconductors $\kappa$-(BEDT-TTF)$_2$$X$ is reported. Temperature and field dependence of heat capacity indicates that the superconductivity has line nodes on the Fermi…
A model is introduced describing the interplay between superconductivity and spin-ordering. It is characterized by on-site repulsive electron-electron interactions, causing antiferromagnetism, and nearest-neighbor attractive interactions,…
We present a theoretical study of flat-band superconductivity for fully spin-polarized triplet pairing with $p$-wave symmetry. We consider the effect of disorder and calculate the disorder-averaged Green's functions diagrammatically in…