Search

• The hot spots connected by the scattering wave vectors q i construct an octet scattering model. • The quasiparticle excitation spectrum is split into its bonding and antibonding components due to the presence of the bilayer coupling. • The peak-dip-hump structure in the quasiparticle excitation spectrum along the Fermi surface is related with the peak-structure in the quasiparticle scattering rate except for at hot spots, where it is caused by the bilayer coupling. • The kink in the quasiparticle dispersion is present all around the Fermi surface. • The characteristic features of the renormalization of the electrons are particularly obvious due to the presence of the bilayer coupling. Cuprate superconductors have a layered structure, and then the physical properties are significantly enriched when two or more two copper-oxide layers are contained in a unit cell. Here the characteristic features of the renormalization of the electrons in the bilayer cuprate superconductors are investigated within the framework of the kinetic-energy driven superconducting mechanism. It is shown that the electron quasiparticle excitation spectrum is split into its bonding and antibonding components due to the presence of the bilayer coupling, with each component that is independent. However, in the underdoped and optimally doped regimes, although the bonding and antibonding electron Fermi surface contours deriving from the bonding and antibonding layers are truncated to form the disconnected bonding and antibonding Fermi arcs, almost all spectral weights in the bonding and antibonding Fermi arcs are reduced to the tips of the bonding and antibonding Fermi arcs, which in this case coincide with the bonding and antibonding hot spots. These hot spots connected by the scattering wave vectors q i construct an octet scattering model, and then the enhancement of the quasiparticle scattering processes with the scattering wave vectors q i is confirmed via the result of the autocorrelation of the electron quasiparticle excitation spectral intensities. Moreover, the peak-dip-hump structure developed in each component of the electron quasiparticle excitation spectrum along the corresponding electron Fermi surface is directly related with the peak structure in the quasiparticle scattering rate except for at around the hot spots, where the peak-dip-hump structure is caused mainly by the pure bilayer coupling. Although the kink in the electron quasiparticle dispersion is present all around the electron Fermi surface, when the momentum moves away from the node to the antinode, the kink energy smoothly decreases, while the dispersion kink becomes more pronounced, and in particular, near the cut close to the antinode, develops into a break separating of the fasting dispersing high-energy part of the electron quasiparticle excitation spectrum from the slower dispersing low-energy part. By comparing with the corresponding results in the single-layer case, the theory also indicates that the characteristic features of the renormalization of the electrons are particularly obvious due to the presence of the bilayer coupling. [ABSTRACT FROM AUTHOR]

One of the central issues in the recent study of cuprate superconductors is the interplay of charge order with superconductivity. Here the interplay of charge order with superconductivity in cuprate superconductors is studied based on the kinetic-energy-driven superconducting (SC) mechanism by taking into account the intertwining between the pseudogap and SC gap. It is shown that the appearance of the Fermi pockets is closely associated with the emergence of the pseudogap. However, the distribution of the spectral weight of the SC-state quasiparticle spectrum on the Fermi arc, or equivalently the front side of the Fermi pocket, and back side of Fermi pocket is extremely anisotropic, where the most part of the spectral weight is located around the tips of the Fermi arcs, which in this case coincide with the hot spots on the electron Fermi surface (EFS). In particular, as charge order in the normal-state, this EFS instability drives charge order in the SC-state, with the charge-order wave vector that is well consistent with the wave vector connecting the hot spots on the straight Fermi arcs. Furthermore, this charge-order state is doping dependent, with the charge-order wave vector that decreases in magnitude with the increase of doping. Although there is a coexistence of charge order and superconductivity, this charge order antagonizes superconductivity. The results from the SC-state dynamical charge structure factor indicate the existence of a quantitative connection between the low-energy electronic structure and collective response of the electron density. The theory also shows that the pseudogap and charge order have a root in common, they and superconductivity are a natural consequence of the strong electron correlation. [ABSTRACT FROM AUTHOR]