Related papers: Doping dependent quasiparticle band structure in c…
Quasiparticle bands of the two-dimensional Hubbard model are calculated using the Roth two-pole approximation to the one particle Green's function. Excellent agreement is obtained with recent Monte Carlo calculations, including an anomalous…
We study possible charge instabilities in doped Mott insulators by employing the two-dimensional t-J model with a positive value of the next nearest-neighbor hopping integral t' on a square lattice, which is applicable to electron-doped…
We study the spin excitations and the transverse susceptibility of a two-dimensional antiferromagnet doped with a small concentration of holes in the t-J model. The motion of holes generates a renormalization of the magnetic properties. The…
Within the t-t'-J model, the doping dependence of the Meissner effect in cuprate superconductors is studied based on the kinetic energy driven superconducting mechanism. Following the linear response theory, it is shown that the…
The doping and temperature dependent conductivity of electron-doped cuprates is analysed. The variation of kinetic energy with doping is shown to imply that the materials are approximately as strongly correlated as the hole-doped materials.…
We perform variational Monte Carlo simulations of the single-band Hubbard model on the square lattice with both nearest ($t$) and next-nearest ($t'$) neighbor hoppings. Our work investigates the consequences of increasing hole doping on the…
The T=0 phase diagram of the planar t--J model with small doping is investigated by exact diagonalisations of square clusters with up to 32 sites. At half-filling, the single hole quasi-particule weight vanishes in the strong correlation…
Spectral functions are evaluated numerically within the t-t'-J model as relevant for electron-doped cuprates. The Fermi surface develops from a pocket-like into a large one with doping. The corresponding pseudogap in the nodal direction is…
We demonstrate that most features ascribed to strong correlation effects in various spectroscopies of the cuprates are captured by a calculation of the self-energy incorporating effects of spin and charge fluctuations. The self energy is…
Recent scanning tunneling spectroscopy experiments have provided evidence that dopant impurities in high- Tc superconductors can strongly modify the electronic structure of the CuO2 planes nearby, and possibly influence the pairing. To…
The electronic Raman response in the electron-doped cuprate superconductors is studied based on the $t$-$t'$-$J$ model. It is shown that although the domelike shape of the doping dependent peak energy in the $B_{2g}$ symmetry is a common…
A spin-charge recombination route to superconductivity, proposed earlier (1992)], is examined using the Schwinger boson representation of the t-J model. The representation is known to work well at half-filling. It was shown in the earlier…
Exact diagonalization studies for a doped t-J ladder (or double chain) show hole pairing in the ground state. The excitation spectrum separates into a limited number of quasiparticles which carry charge $+|e|$ and spin ${1 \over 2}$ and a…
We calculate the quasiparticle dispersion and spectral weight of the quasiparticle that results when a hole is added to an antiferromagnetically ordered CuO$_2$ plane of a cuprate superconductor. We also calculate the magnon contribution to…
The next-nearest-neighbour hopping term t' is shown to stabilize the AF state of the doped Hubbard model with respect to transverse perturbations in the order- parameter by strongly suppressing the intraband particle-hole processes. For a…
There are two commonly discussed points of view in theoretical description of cuprate superconductors, (i) Cuprates can be described by the modified t-J model. (ii) Overdoped cuprates are close to the regime of normal Fermi liquid (NFL). We…
It is shown that spectral functions within the extended t-J model, evaluated using the finite-temperature diagonalization of small clusters, exhibit the high-energy kink in single-particle dispersion consistent with recent angle-resolved…
We investigate the effect of hole doping on the strong-coupling Hubbard model at half-filling in spatial dimensions $D\ge 1$. We start with an antiferromagnetic mean-field description of the insulating state, and show that doping creates…
In this study, we analyze the dielectric function of high-Tc cuprates as a function of doping level, taking into account the full energy band dispersion within the CuO$_2$ monolayer. In addition to the conventional two-dimensional (2D)…
By comparing single-particle spectral functions of t-J and Hubbard models with recent angle-resolved photoemission (ARPES) results for LSCO and Nd-LSCO, we can decide where holes go as a function of doping, and more specifically, which type…