Related papers: Origin of the maximal critical temperature dispari…
Recently an apical oxygen atoms vibrations exchange mechanism of d-wave pairing in cuprates was proposed. The phonon mode in an insulating layer generates attraction of holes in metallic cuper oxygen planes. The pairing has a maximum at the…
The model for the cuprates based on the modified electron-phonon pairing mechanism has been tested. For this purpose, the superconductors with high value of the critical temperature have been taken into consideration. In particular: ${\rm…
In conventional superconductors, phonons glue two electrons with opposite spins to form Cooper pairs and condensation of these pairs leads to the superconductivity. Identifying the underlying mechanism of the high temperature…
The large variations of T$_c$ across the cuprate families is one of the major unsolved puzzles in condensed matter physics, and is poorly understood. Although there appears to be a great deal of universality in the cuprates, several orders…
When the electron-phonon coupling is quadratic in the phonon coordinates, electrons can pair to form bipolarons due to phonon zero-point fluctuations, a purely quantum effect. We study superconductivity originating from this pairing…
In cuprate superconductors, a pronounced maximum of superconducting Tc is observed in compounds that have an in-plane Cu-O distance close to ~1.92 Angstroms. On the other hand, direct measurements of the electron-phonon coupling lambda as a…
Superconducting transition temperature is calculated for differently doped bilayer cuprates. Superexchange is assumed to be the dominating mechanism of high-temperature superconductivity, but the contribution from the phonon potential is…
Since conventional superconductivity is mediated by phonons, their role in the mechanism of high temperature superconductivity has been considered very early after the discovery of the cuprates. The initial consensus was that phonons could…
Using high resolution angle-resolved photoemission data in conjunction with that from neutron and other probes, we show that electron-phonon (el-ph) coupling is strong in cuprates superconductors and it plays an important role in pairing.…
Topological phononic insulators are the counterpart of three-dimensional quantum spin Hall insulators in phononic systems and, as such, their topological surfaces are characterized by Dirac cone-shaped gapless edge states arising as a…
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…
The experimentally observed difference of superconducting critical temperature $T_{c}$ in hole-doped cuprates is studied by using an extended interlayer coupling model for layered d-wave superconductors. We show that the change of the…
The electron-phonon interaction is a major factor influencing the competition between collective instabilities in correlated-electron materials, but its role in driving high-temperature superconductivity in the cuprates remains poorly…
We study the electronic structures of two single layer superconducting cuprates, Tl$_2$Ba$_2$CuO$_{6+\delta}$ (Tl2201) and (Bi$_{1.35}$Pb$_{0.85}$)(Sr$_{1.47}$La$_{0.38}$)CuO$_{6+\delta}$ (Bi2201) which have very different maximum critical…
The room temperature thermal diffusivity of high T$_c$ materials is dominated by phonons. This allows the scattering of phonons by electrons to be discerned. We argue that the measured strength of this scattering suggests a converse…
Superconductivity is a quantum phenomenon caused by bound pairs of electrons. In diverse families of strongly correlated electron systems, the electron pairs are not bound together by phonon exchange but instead by some other kind of…
In conventional, phonon-mediated superconductors, the transition temperature $T_c$ and normal-state scattering rate $1/\tau$ - deduced from the linear-in-temperature resistivity $\rho(T)$ - are linked through the electron-phonon coupling…
The electron-phonon and spin-phonon coupling in typical high-T_C cuprates, like LSCO and HBCO are peaked for just a few q-vectors because of the 2-dimensional Fermi surface shape. The activation of few spin-phonon modes compensates for the…
Starting from a spin-fermion model for the cuprate superconductors, we obtain an effective interaction for the charge carriers by integrating out the spin degrees of freedom. Our model predicts a quantum critical point for the…
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.…