Fig. 1
Temperature-dependent ARPES spectra and self-energies. a–f Measured spectra from a mid-zone cut (s) of the antibonding band at multiple temperatures. g–l 2D fits to the corresponding ARPES spectra, with the main unknown parameters the superconducting gaps, the electronic self-energies and the bare electron band, where the dotted curve is the bare-band dispersion from the fitting. m–r Correspondent self-energies extracted from the fit spectra on the left. t Imaginary part of the self-energy Σ″ (or scattering rate) vs. frequency and temperature obtained from the 2D fits. There is a strong reduction or gapping of the near E F scattering rate as temperature is lowered into the paired state, along with a shift of this scattering to high energies beyond the dashed line. Along with this is a strong kink or mass enhancement in the real part of self-energy Σ′ (u). These effects of Σ″ and Σ′ are responsible for the dramatic flattening and sharpening of the low-energy states of a–f, g–l. All data were taken with 9 eV photons, and the Fermi surface angle was θ = 22.5 degree
