Looking Beyond the Surface with Angle-Resolved Photoemission Spectroscopy.

The issue of surface sensitivity, and its relationship with interpretation of spectral features observed in angle-resolved photoemission spectroscopy experiments is investigated. Rather than attempt to make an explicit connection to bulk electronic structure calculations, we take the new approach of exploring this issue within the natural context of a vacuum-terminated crystalline slab. Doing so, we reconcile the empirical reality of reliable kz fidelity with acute surface sensitivity of this technique. In addition, we identify several critical issues which impact the estimation of kF , band velocity, and self-energy from photoemission experiments.