Related papers: Two-dimensional t-J model at moderate doping
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…
The relaxation function theory of doped two-dimensional $S=1/2$ Heisenberg antiferromagnetic (AF) system in the paramagnetic state is presented taking into account the hole subsystem as well as both the electron and AF correlations. The…
We study the t-J model with four holes on a 32-site square lattice using exact diagonalization. This system corresponds to doping level x=1/8. At the ``realistic'' parameter J/t=0.3, holes in the ground state of this system are unbound.…
Using cluster perturbation theory, it is shown that the spectral weight and pseudogap observed at the Fermi energy in recent Angle Resolved Photoemission Spectroscopy (ARPES) of both electron and hole-doped high-temperature superconductors…
Several thermodynamic quantities within the planar $t-J$ model are calculated using the $T>0$ Lanczos method on clusters of up to 26 sites. Hole density $c_h(\mu,T)$ shows a non-Fermi liquid behavior as a function of $T$ and suggests a…
A detailed exact-diagonalization study is made for the doping dependence of the single-particle spectral function $A({\bf k},\omega)$ and momentum distribution function $n({\bf k})$ of the two-dimensional $t$$-$$J$ model as a representative…
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 an explanation of several experimental features of transport phenomena in the normal state of high Tc cuprates in terms of a spin-charge gauge theory of the 2D t-J model. The calculated doping-temperature dependence for a number…
There is growing evidence that the hole-doped single-band Hubbard and $t$-$J$ models do not have a superconducting ground state reflective of the high-temperature cuprate superconductors but instead have striped spin- and charge-ordered…
Using Gutzwiller-projected wave functions, I estimate the ground-state energy of the t-J model for several variational states relevant for high-temperature cuprate superconductors. The results indicate antiferromagnetism and phase…
We assume the t-t'-J model to describe the CuO_2 planes of hole-doped cuprates and we adapt the spin-charge gauge approach, previously developed for the t-J model, to describe the holes in terms of a spinless fermion carrying the charge…
We present an exact diagonalization study of the single particle spectral function in the so-called t-t'-t''-J model in 2D. As a key result, we find that unlike the `pure' t-J model, hole doping leads to a major reconstruction of the…
The energy spectrum of the two-dimensional t-J model in a perpendicular magnetic field is investigated. The density of states at the Fermi level as a function of the inverse magnetic field $\frac{1}{B}$ reveals oscillations in the range of…
We carry out a systematic study of collective spin- and charge excitations for the canonical single-band Hubbard, $t$-$J$-$U$, and $t$-$J$ models of high-temperature copper-oxide superconductors, both on electron- and hole-doped side of the…
The dispersion of one hole in an extended $t$-$J$ model with additional hopping terms to second and third nearest neighbours and a frustration term in the exchange part has been investigated. Two methods, a Green's function projection…
The effects on the correlated Cu^{2+} S = 1/2 spin dynamics in the paramagnetic phase of La_{2-x}Sr_xCuO_4 (for $x \lesssim 0.04$) due to the injection of holes are studied by means of ^{63}Cu NQR spin-lattice relaxation time T_1…
We study the pairing properties of the two-dimensional $t$-$t'$-$t''$-$J$ model, where $t'$ and $t''$ are second and third neighbor hoppings, at a doping level $x\approx0.1$. Recent studies of the $t$-$t'$-$J$ model find strong pairing for…
We have investigated the evolution of the electronic properties of the t-t'-U Hubbard model with hole doping and temperature. Due to the shape of the Fermi surface, scattering from short wavelength spin fluctuations leads to strongly…
Within the t-t'-J model, the charge asymmetry in superconductivity of hole- and electron-doped cuprates is studied based on the kinetic energy driven superconducting mechanism. It is shown that superconductivity appears over a narrow range…
Finite-temperature properties of weakly doped antiferromagnets as modeled by the two-dimensional t-J model and relevant to underdoped cuprates are investigated by numerical studies of small model systems at low doping. Two numerical methods…