Related papers: Superconductivity in the two-dimensional t-J model
There is a consensus that superconductivity (SC) in cuprates is two-dimensional. It is widely believed that the long-range phase coherence appears at T_{c} due to the Josephson coupling between SC CuO_{2} (bi-, tri-, >...)layers. Recent…
Experimental studies of magnetoresistance in thin superconducting strips subject to a perpendicular magnetic field B exhibit a multitude of transitions, from superconductor to insulator and vice versa alternately. Motivated by this…
If the topological insulator Bi$_{2}$Se$_{3}$ is doped with electrons, superconductivity with $T_{{\rm c}}\approx3-4\:{\rm K}$ emerges for a low density of carriers ($n\approx10^{20}{\rm cm}^{-3}$) and with a small ratio of the…
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…
We argue that effective 1D models of stripes in the cuprate superconductors can be constructed by studying ground states and elementary excitations of domain walls in 2D model antiferromagnets. This method, applied to the t-J model with…
Rapid miniaturization of electronic devices and circuits demands profound understanding of fluctuation phenomena at the nanoscale. Superconducting nanowires -- serving as important building blocks for such devices -- may seriously suffer…
We investigate the highly incoherent regime of hole-doped 2d Mott-Hubbard insulators at moderately small doping and temperatures T>=0.1J, where J is the exchange coupling. Within an extended dynamical mean-field theory of the t-J model and…
The bilayer Hubbard model with an intra-layer hopping $t$ and an inter-layer hopping $t_\perp$ provides an interesting testing ground for several aspects of what has been called unconventional superconductivity. One can study the type of…
We consider the repulsive Hubbard model on a square lattice with an additional term, W, which depends upon the square of a single-particle nearest-neighbor hopping. At half-band filling, constant W, we show that enhancing U/t drives the…
Bipartite charge fluctuations (BCF) have been introduced to provide an experimental indication of many-body entanglement. They have proved themselves to be a very efficient and useful tool to characterize quantum phase transitions in a…
The variety of the normal-state magnetic properties of cuprate high-Tc superconductors is interpreted based on the self-consistent solution of the self-energy equations for the two-dimensional t-J model. The observed variations of the spin…
Three-dimensional doped Dirac insulators foster simply connected (in both topological and trivial regimes) and annular (deep inside the topological regime) Fermi surfaces (FSs) in the normal state, and allow on-site repulsions among…
Mobile holes in an antiferromagnetic insulator form a slowly fluctuating array of quasi one-dimensional metallic stripes, which induce a spin gap or pseudogap in the intervening Mott-insulating regions. The mobile holes on an individual…
The quarter-filling extended Hubbard model on the triangular lattice is studied to explore pairing instability in the three-fold charge-ordered (CO) metal. We derive a second-order strong-coupling effective Hamiltonian of doped carriers…
We present a self-consistent approach to deal with the pairing-fluctuation effects in quasi-two-dimensional superconducting systems. Besides the Cooper pairs in the Bose-Einstein condensate, there are pairs occupying the excited states,…
The recent discovery of superconductivity under high pressure in the ladder compound BaFe$_2$S$_3$ has opened a new field of research in iron-based superconductors with focus on quasi one-dimensional geometries. In this publication, using…
We investigate the large Kondo coupling limit of the Kondo-Heisenberg model on one- and two-dimensional lattices. Focusing on the possible superconducting states when slightly doping the Kondo insulator state, we identify different pairing…
Using the structural data of the La2CuO4 compound both in the low temperature tetragonal phase and in the isotropic phase we have derived an effective t-J model with hoppings t and superexchange interactions J extended up to fourth and…
We study the Mott transition occurring for bosonic Hubbard models in one, two, and three spatial dimensions, by means of a variational wave function benchmarked by Green's function Monte Carlo calculations. We show that a very accurate…
We explore the superconducting properties of the bilayer Hubbard model, which exhibits a high transition temperature ($T_{\rm c}$) for an $s_{\pm}$ pairing, using a cluster extension of the dynamical mean-field theory. Unlike the…