Related papers: Pairing Glue in the Two Dimensional Hubbard Model
The experimental investigations done in our paper Phys.Rev.B84,014522(2011) allowed us to establish that the superconducting fluctuations (SCF) always die out sharply with increasing T. But contrary to the claim done in the comment of…
Superconductivity was recently observed in boron-doped ($\sqrt{3}\times\sqrt{3}$)Sn/Si(111). The material can be described by an extended Hubbard model on a triangular lattice. Here, we use the random-phase approximation to investigate the…
We theoretically investigate the electric transport in the pseudogap state of High-Tc cuprates. Starting from the repulsive Hubbard model, we perform the microscopic calculation to describe the pseudogap phenomena which are induced by the…
I show that for a \kappa-type organic (BEDT-TTF)_2-X molecular crystal, a superconducting state with T_c ~ 10 K and gap nodes on the Fermi surface can be caused by short-ranged antiferromagnetic spin fluctuations. Using a two-band…
We calculate spectral functions within the t-J model as relevant to cuprates in the regime from low to optimum doping. On the basis of equations of motion for projected operators an effective spin-fermion coupling is derived. The self…
We propose a formalism to take account of the correction of the spatial fluctuations to the local self-energy obtained by the dynamical mean-field approximation. For this purpose, the approximate dynamical susceptibility in the framework of…
Observation of robust superconductivity in some of the iron based superconductors in the vicinity of a Lifshitz point where a spin density wave instability is suppressed as the {hole} band drops below the Fermi energy raise questions for…
When holes move in the background of strong antiferromagnetic correlation, two effects with different spatial scale emerge, leading to a much reduced hopping integral with an additional phase factor. An effective Hamiltonian is then…
Superconductivity in cuprates is achieved by doping holes into a correlated charge-transfer insulator. While the correlated character of the parent insulator is now understood, there is no accepted theory for the "normal" state of the doped…
The interactions between holes in the Hubbard model, in the low density, intermediate to strong coupling limit, are investigated. Dressed spin polarons in neighboring sites have an increased kinetic energy and an enhanced hopping rate. Both…
A phase diagram is drawn in a parameter space of the nearly half-filled single band two-dimensional Hubbard model with U/t, t'/t and n as the parameters, U, t, t' and n being the on-site interaction, the nearest and second nearest neighbor…
Superconductivity in heavy-fermion materials can sometimes appear in the incoherent regime and in proximity to an antiferromagnetic quantum critical point. Here we study these phenomena using large scale determinant quantum Monte Carlo…
We investigate the ground-state properties of the two-dimensional Hubbard model, based on the off-diagonal wave function variational Monte Carlo method. We use an optimized wave function that is improved from an initial one-body wave…
The ground state of the two-dimensional (2D) Hubbard model is investigated by adopting improved wave functions that take into account intersite electron correlation beyond the Gutzwiller ansatz. The ground-state energy is lowered…
The attractive Fermi-Hubbard model is the simplest theoretical model for studying pairing and superconductivity of fermions on a lattice. Although its s-wave pairing symmetry excludes it as a microscopic model for high-temperature…
In order to check whether odd-numbered Tomonaga-Luttinger ladders are dominated by antiferromagnetic correlations associated with gapless spin excitations, correlation functions of the doped three-chain Hubbard model are obtained with the…
The Su-Schrieffer-Heeger model describes fermions that hop on a one-dimensional chain with staggered hopping amplitude, where the unit cell contains two sites, or two sublattices. In this work we consider the Su-Schrieffer-Heeger model with…
The properties of the two-chain Hubbard Model doped away from half-filling are investigated. The charge gap is found to vanish, but a finite spin gap exists over a range of interchain hopping strength $t_\perp$. In this range, there are…
Using the strong coupling diagram technique for calculating the electron Green's function of the two-dimensional Hubbard model we have summed infinite sequences of ladder diagrams, which describe interactions of electrons with spin and…
Dynamical properties are notoriously difficult to compute in numerical treatments of the Fermi-Hubbard model, especially in two spatial dimensions. However, they are essential in providing us with insight into some of the most important and…