Related papers: Generalized one-band model based on Zhang-Rice sin…

In cuprate superconductors doping is believed to create holes on the O-sites, which couple antiferromagnetically with holes on the Cu-sites to form the so-called Zhang-Rice singlets. Here we study a d-wave pairing state based on the…

The single-particle spectral functions $A({\bf k},\omega)$ and self-energies $\Sigma({\bf k},\omega)$ are calculated within the $t-J$ model using the finite-temperature Lanczos method for small systems. A remarkable asymmetry between the…

Quadrupole and octupole deformation energy surfaces, low-energy excitation spectra and transition rates in fourteen isotopic chains: Xe, Ba, Ce, Nd, Sm, Gd, Rn, Ra, Th, U, Pu, Cm, Cf, and Fm, are systematically analyzed using a theoretical…

Within the Composite Operator Method (COM), we report the solution of the Emery model (also known as p-d or three band model), which is relevant for the cuprate high-Tc superconduc- tors. We also discuss the relevance of the often-neglected…

We explore the possibility to control the superconducting (SC) transition temperature at optimal hole doping $T_{c}^{\rm opt}$ in cuprates by tuning the chemical formula (CF). $T_{c}^{\rm opt}$ can be theoretically predicted from the…

This paper is devoted to an elementary new construction of $1$-singular Gelfand-Tsetlin modules using complex geometry. We introduce a universal ring $\mathcal D_o$ together with the vector space $\mathcal S=\mathcal S(\mathcal D_o)$ with…

This note gives the complete projective classification of rational, cuspidal plane curves of degree at least 6, and having only weighted homogeneous singularities. It also sheds new light on some previous characterizations of free and…

We examine a realistic 3-band model, finding it capable of exhibiting the d-wave pairing characteristic of CuO2-based high-Tc superconductors, but only in the presence of symmetry-lowering charge-density stripes aligned along (1,0) axes,…

Spectroscopy experiments are routinely used to characterize the behavior of strongly correlated systems. An in-depth understanding of the different spectral features is thus essential. Here, we show that the spectrum of the multiorbital…

The regions of hole concentrations $0 \leq x \alt 0.3$ and temperatures $0.005|t| \leq T \leq 0.02|t|$ are studied in the t-J model of Cu-O planes of perovskite high-$T_c$ superconductors. For this purpose self-energy equations for hole and…

We examine spectral properties of doped holes dressed with surrounding spin cloud in the t-J model. These composite-hole excitations well characterize prominent band structures in the angle-resolved photoemission spectrum. In…

In order to investigate the electronic state of Ce-free and Ce-underdoped high-Tc cuprates with the so-called T' structure, we have performed muon-spin-relaxation (muSR) and specific-heat measurements of Ce-free T'-La_1.8_Eu_0.2_CuO_4+d_…

We study one and two hole properties of the t-J model at half-filling on the square lattice using series expansion methods at T=0. The dispersion curve for one hole excitations is calculated and found to be qualitatively similar to that…

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…

The t-J_z model is the strongly anisotropic limit of the t-J model which captures some general properties of the doped antiferromagnets (AF). The absence of spin fluctuations simplifies the analytical treatment of hole motion in an AF…

Using the example of the sawtooth chain, we argue that the t-J model shares important features with the Hubbard model on highly frustrated lattices. The lowest single-fermion band is completely flat (for a specific choice of the hopping…

Using a combination of local density functional theory and cluster exact diagonalization based dynamical mean field theory, we calculate many body electronic structures of several Mott insulating oxides including undoped high T_{c}…

We formulate charge transfer model for a single doped spin ladder, relevant for the intrinsically doped plane of coupled spin ladders in Sr$_{3}$Ca$_{11}$Cu$_{24}$O$_{41}$. Assuming the presence of the experimentally observed charge order…

In the present work the multiband p-d model for $CuO_2$-layer is treated. It was shown that for the realistic set of parameters besides Zhang-Rice two-particle singlet there is non-negligible contribution of two-particle triplet state to…

I discuss various direct calculations of the properties of the one-band Hubbard model on a square lattice and conclude that these properties sufficiently resemble those of the cuprate superconductors that no more complicated interactions…