Related papers: Projected Wavefunctions and High Temperature Super…
We consider the slave-fermion Schwinger-boson decomposition of an effective model obtained through a systematic low-energy reduction of the three-band Hubbard Hamiltonian. The model includes a three-site term t'' similar to that obtained in…
The optical conductivity and Drude weight of a Spin-Fermion model for cuprates are studied as a function of electronic density and temperature. This model develops stripes and robust D-wave pairing correlation upon hole doping, and it has…
Based on the Hubbard model in the framework of non-phonon kinematical mechanism and taking into account the discreetness of an electronic energy spectrum, the superconducting critical temperature of a mesoscopic high-$T_{c}$ sphere is…
We define a `hyperconductor' to be a material whose electrical and thermal DC conductivities are infinite at zero temperature and finite at any non-zero temperature. The low-temperature behavior of a hyperconductor is controlled by a…
A model of superconductivity in layered high-temperature superconducting cuprates is proposed, based on the extended saddle point singularities in the electron spectrum, weak screening of the Coulomb interaction and phonon-mediated…
In light of recent experimental evidence of density wave order in the cuprates, we consider a phenomenological model of a d-wave superconductor with coexisting charge, spin or pair density wave order of various form and wave vector. We…
We have performed an angle-resolved photoemission study of the nodal quasi-particle spectra of the high-Tc cuprate tri-layer Bi2Sr2Ca2Cu3O10+d (Tc~ 110 K). The spectral weight Z of the nodal quasi-particle increases with decreasing…
To address the issues of superconducting and charge properties in high-T$_c$ cuprates, we perform a quantum Monte Carlo study of an extended three-band Emery model, which explicitly includes attractive interaction $V_{OO}$ between oxygen…
Interplay between antiferromagnetism and superconductivity is studied by using the 3-dimensional nearly half-filled Hubbard model with anisotropic transfer matrices $t_{\rm z}$ and $t_{\perp}$. The phase diagrams are calculated for varying…
Based on a Fermi liquid model, we present several results on the normal state of the optimally doped and overdoped cuprate superconductors. Our main result is an analytic demonstration, backed by self-consistent numerical calculations, of…
The phase fluctuations of the condensate in doped antiferromagnets, described by a t-t'-J model and a suitable 1/N expansion, provide a mechanism for a Kosterlitz-Thouless (KT) type of transition to a superconducting state below T_{c}. In…
When a van-Hove singularity is located in the vicinity of the Fermi level, the electronic scattering rate acquires a non-analytic contribution. This invalidates basic assumptions of Fermi liquid theory and within perturbative treatments…
In the last few years charge density waves (CDWs) have been ubiquitously observed in high-temperature superconducting cuprates and are now the most investigated among the competing orders in the still hot debate on these systems. A wealth…
By means of magnetization, specific heat and muon-spin relaxation measurements, we investigate high-pressure oxidized \mohpo, in which overdoping is achieved up to $p \sim 0.45$ hole/Cu, well beyond the $T_c - p$ superconducting dome of…
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…
I review progress in measurements of the dynamic spin susceptibility in the normal state which yield a new phase diagram and discuss microscopic calculations which yield qualitative, and in many cases, quantitative agreement with the…
The physical properties of low energy superconducting quasiparticles in high- $T_c$ superconductors are examined using magnetic penetration depth and specific heat experimental data. We find that the low energy density of states of…
Microwave conductivity experiments can directly measure the quasiparticle scattering rate in the superconducting state. We show that this, combined with knowledge of the Fermi surface geometry, allows one to distinguish between closely…
A model of charged hole-pair bosons, with long range Coulomb interactions and very weak interlayer coupling, is used to calculate the order parameter -Phi- of underdoped cuprates. Model parameters are extracted from experimental superfluid…
We study superconductivity in two-band models where one of the bands does or does not intersect the Fermi level depending on the parameter values. Applying a many-variable variational Monte-Carlo method for a Hubbard model on two-leg ladder…