View article

The angle-resolved photoelectron spectroscopy (ARPES) spectra in high- superconductors show four distinctive features in the quasiparticle self-energy . They can be explained consistently by the phenomenological microscopic theory in which the electron-phonon interaction with the forward-scattering peak dominates over the Coulomb scattering. This theory explains why there is no shift of the nodal kink at in the superconducting state, contrary to the observed shift of the antinodal singularity at . The theory predicts a kneelike structure of , which is phonon dominated, ∣ImΣ(ωph)∣≈∣ImΣph(ωph)∣∼πλphωph∕2, for , and for shows linear behavior , due to the Coulomb scattering. ARPES spectra give —which is obtained from , and —obtained from , i.e., . The dip-hump structure …