Related papers: Robust dx2-y2 pairing symmetry in high-temperature…
We propose a weakly coupled two-band model with $d_{x^2-y^2}$ pairing symmetry to account for the anomalous temperature dependence of superfluid density $\rho_s$ in electron-doped cuprate superconductors. This model gives a unified…
Scanning tunneling spectroscopy (STS) studies reveal long-range spatial homogeneity and predominantly $d_{x^2-y^2}$-pairing spectral characteristics in under- and optimally doped $\rm YBa_2Cu_3O_{7-\delta}$ superconductors, whereas STS on…
The pairing symmetry of the newly proposed cobalt high temperature (high-$T_c$) superconductors formed by vertex shared cation-anion tetrahedral complexes is studied by the methods of mean field, random phase approximation (RPA) and…
Using as a model the Hubbard Hamiltonian we determine various basic properties of electron-doped cuprate superconductors like ${Nd}_{2-x}{Ce}_{x}{CuO}_{4}$ and ${Pr}_{2-x}{Ce}_{x}{CuO}_{4}$ for a spin-fluctuation-induced pairing mechanism.…
It is shown that an account for the space separatedness of the two-orbital subsystem of the oxygen holes and the subsystem of the localized spins of copper ions in high-T$_c$ cuprate superconductors leads to the stability of the…
Absolute resistivity measurements as a function of temperature from optimally doped YBa_2Cu_3O_(7), La_(2-x)Sr_xCuO_4, Bi_2Sr_2CaCu_2O_(8-x), and (Ca_0.1La_0.9)(Ba_1.65La_0.35)Cu_3O_y thin films are reported. Special attention is given to…
Phase-sensitive tests of pairing symmetry have provided strong evidence for predominantly d-wave pairing symmetry in both hole- and electron-doped high-Tc cuprate superconductors. Temperature dependent measurements in YBCO indicate that the…
The doping and temperature dependence of the electronic Raman response in cuprate superconductors is studied within the framework of the kinetic energy driven superconducting mechanism for the t-J model. It is shown that the temperature…
We show that the doping-controlled superconductor-insulator transition (SIT) in a high critical temperature cuprate system (Bi2Sr2-xLaxCaCu2O8+delta) exhibits a fundamentally different behavior than is expected from conventional SIT. At the…
We review and extend a previous study on the symmetry of the superconducting state, stimulated by recent tunneling and Andreev reflection measurements giving robust evidences for the existence of a $d_{x^2-y^2}+id_{xy}$ order parameter in…
We show that doping-induced charge fluctuations in strongly correlated Hubbard electron systems near the 1/2-filled, insulating limit cause overscreening of the electron-electron Coulomb repulsion. The resulting attractive screened…
We study two aspects of the superconductivity in a cuprate model system, its doping dependence and the influence of competing pairing mediators. We first include electron-phonon interactions beyond Migdal's approximation and solve…
We report on the ab-plane reflectance of the high temperature superconductor Bi2Sr2CaCu2O8+d (Bi-2212). Samples spanning the doping range from under doped with Tc = 67 K(UD), to optimally doped with Tc = 96 K (OPT), to over doped with Tc =…
We present a simple theoretical explanation for a transition from d-wave to another superconducting pairing observed in the electron-doped cuprates. The d_{x^2-y^2} pairing potential Delta, which has the maximal magnitude and opposite signs…
The superconducting properties of a recently proposed phenomenological model for a weakly doped antiferromagnet are analyzed, taking into account fluctuations of the phase of the order parameter. In this model, we assume that the doped…
Within a Hubbard model, we investigate the superconducting pairing behavior of infinite-layer nickelate $\mathrm{NdNiO_2}$ and cuprate superconductors by using the determinant quantum Monte Carlo method. Our focus is on comparing their…
We report a brief overview ofa number of results on a type of pairing state symmetry in cuprates HTSC from a current literature. The results of recent high-precision measurements of near-nodal d-type gap functions by a modern laser-based…
We present measurements of the magnetic penetration depth, \lambda^{-2}(T), in Pr_{2-x}Ce_{x}CuO_{4-y} and La_{2-x}Ce_{x}CuO_{4-y} films at three Ce doping levels, x, near optimal. Optimal and overdoped films are qualitatively and…
Using high-resolution extreme ultraviolet resonant inelastic X-ray scattering (EUVRIXS) spectroscopy at Cu M-edge, we observed the doping dependent spectral shifts of inter-orbital (dd) excitations of YBa_2Cu_3O_(7-x) and La_(2-x)Sr_xCuO_4.…
We performed Raman experiments on superconducting ${\rm Bi_2 Sr_2 (Ca_{1-x} Y_x) Cu_2 O_{8+\delta}}$ (Bi-2212) and ${\rm YBa_{2} Cu_{3}O_{6+x}}$ (Y-123) single crystals. These results in combination with earlier ones enable us to analyze…