Final-state band structure-induced modulations of the photoemission linewidth in angle-resolved valence band spectra: a case study on Bi(1 1 1)

Abstract

The peak width in angle-resolved photoemission spectra from 3D valence bands in Bi(1 1 1) has been analyzed as a function of final-state energy. Over the photon energy range of 9–100 eV valence band transitions display pronounced oscillations with minima at the Γ and T points. The maxima in-between these points are additionally modulated through transitions into multiple final-state bands. Model calculations show that the 3D linewidth is a function of the initial- and final-state widths as well as the respective band velocities v ⊥ = ℏ − 1 ∂ E / ∂ k ⊥ . Extending the model calculations past the commonly used linear approximation by using experimentally determined dispersion relations E ( k ) of initial- and final-state bands significantly improves the linewidth changes in regions near the symmetry points.