Electronic structure of kinetic energy driven superconductors in the presence of bilayer splitting

Abstract

Within the framework of the kinetic energy driven superconductivity, the electronic structure of bilayer cuprate superconductors in the superconducting state is studied. It is shown that the electron spectrum of bilayer cuprate superconductors is split into the bonding and antibonding components by the bilayer splitting, and the observed peak-dip-hump structure around the ͓ ,0͔ point is mainly caused by this bilayer splitting, with the superconducting peak being related to the antibonding component and the hump being formed by the bonding component. The spectral weight increases with increasing doping concentration. In analogy to the normal-state case, both electron antibonding peak and bonding hump have the weak dispersions around the ͓ ,0͔ point.

Electronic Structure of Kinetic Energy Driven Cuprate Superconductors

“…We show that in both superconducting and normal states, the spectral weight increases with increasing doping, and decreases with increasing temperatures [32,33,34,35,36,37]. Furthermore, the superconducting quasiparticles around the [π, 0] point disperse very weakly with momentum [35,37]. In corresponding to this weak dispersions in the superconducting state, the quasiparticle dispersions in the normal state exhibit the flat band around the [π, 0] point just below the Fermi energy [34,36].…”

“…In this paper, we give a brief review of our recent studies for the low energy electronic structure of the kinetic energy driven d-wave cuprate superconductors [32,33,34,35,36,37]. We show that in both superconducting and normal states, the spectral weight increases with increasing doping, and decreases with increasing temperatures [32,33,34,35,36,37]. Furthermore, the superconducting quasiparticles around the [π, 0] point disperse very weakly with momentum [35,37].…”

“…In particular, we show that one of the universal features is that the d-wave superconducting state in cuprate superconductors is the conventional BCS like, so that the basic BCS formalism with the d-wave symmetry is still valid in discussions of the low energy electronic structure of cuprate superconductors [32,33,35,37], although the pairing mechanism is driven by the kinetic energy by exchanging spin excitations, and other exotic magnetic properties [16,17,18] are beyond the BCS formalism. Our these theoretical results [32,33,34,35,36,37] also show that the striking behavior of the electronic structure in cuprate superconductors is intriguingly related to the strong coupling between the electron quasiparticles and collective magnetic excitations. This paper is organized as follows.…”

“…In particular, this superconducting state is the conventional BCS like with the d-wave symmetry, and is controlled by both superconducting gap function and quasiparticle coherence, then the maximal superconducting transition temperature occurs around the optimal doping, and decreases in both underdoped and overdoped regimes [31]. Within this framework of the kinetic energy driven superconductivity, we [32,33,34,35,36,37] have performed a systematic calculation for the low energy electron spectral function of the single layer and bilayer cuprate superconductors in both superconducting and normal states, and qualitatively reproduced all main features of the ARPES experimental measurements on the single layer and bilayer cuprate superconductors [4,5]. In this paper, we give a brief review of our recent studies for the low energy electronic structure of the kinetic energy driven d-wave cuprate superconductors [32,33,34,35,36,37].…”

“…Within this framework of the kinetic energy driven superconductivity, we [32,33,34,35,36,37] have performed a systematic calculation for the low energy electron spectral function of the single layer and bilayer cuprate superconductors in both superconducting and normal states, and qualitatively reproduced all main features of the ARPES experimental measurements on the single layer and bilayer cuprate superconductors [4,5]. In this paper, we give a brief review of our recent studies for the low energy electronic structure of the kinetic energy driven d-wave cuprate superconductors [32,33,34,35,36,37]. We show that in both superconducting and normal states, the spectral weight increases with increasing doping, and decreases with increasing temperatures [32,33,34,35,36,37].…”