Simulating angle-resolved photoemission intensity maps

Full text: Angle-resolved photoemission spectroscopy (ARPES) is a powerful technique that allows the direct observation of a solid crystal's electronic structure. ARPES intensity maps as a function of emitted photoelectron kinetic energy and wave vector k are often interpreted by overlaying calculated band structures on them, applying a slight energy offset to obtain a reasonable theory-experiment visual match. Nowadays, electronic band structures can be computed relatively quickly using Kohn-Sham density functional theory, an independent-electron method that returns allowed energy levels of an electron that moves in a periodic potential created by its interaction with atomic nuclei of the lattice and the surrounding sea of electrons. But ARPES intensity maps provide even more information: fundamental many-body phenomena in an interacting Fermi-liquid system can be discovered through experimental signatures in the ARPES intensity. It is with the aim of a more accurate interpretation of photoemission data that several projects simulating ARPES intensity maps have been developed over the past decade. In this talk we evaluate how well the tight-binding method is in reproducing photoemission maps for two 2D materials (graphene and MoS₂) as well as for the fcc transition metals copper and gold. (author)