Momentum dependence of quasiparticle spectrum and Bogoliubov angle in cuprate superconductors

TL;DR

This paper investigates how the quasiparticle spectrum and Bogoliubov angle vary with momentum in cuprate superconductors, revealing a monotonic increase of the Bogoliubov angle across the Fermi crossing and supporting a kinetic energy-driven pairing mechanism.

Contribution

It demonstrates that the low energy quasiparticle spectrum and Bogoliubov angle can be described within a kinetic energy driven framework, aligning with a simple d-wave BCS formalism.

Findings

Bogoliubov angle increases monotonically across the Fermi crossing

Superconducting coherence is well described by d-wave BCS formalism

Kinetic energy driven pairing mechanism explains the results

Abstract

The momentum dependence of the low energy quasiparticle spectrum and the related Bogoliubov angle in cuprate superconductors are studied within the kinetic energy driven superconducting mechanism. By calculation of the ratio of the low energy quasiparticle spectra at positive and negative energies, it is shown that the Bogoliubov angle increase monotonically across the Fermi crossing point. The results also show that the superconducting coherence of the low energy quasiparticle peak is well described by a simple d-wave Bardeen-Cooper-Schrieffer formalism, although the pairing mechanism is driven by the kinetic energy by exchanging spin excitations.