Accurate and efficient simulation of photoemission spectroscopy via Kohn-Sham scattering states

Abstract: We introduce an efficient first-principles framework for simulating angle-resolved photoemission spectroscopy (ARPES) by computing photoelectron states as solutions of the Kohn-Sham equation with scattering boundary conditions. This approach is formally equivalent to the Lippmann-Schwinger formalism but offers superior computational efficiency and direct integration with plane-wave or real-space density functional theory. By enabling direct calculation of photoemission matrix elements, our method bridges the gap between intrinsic electronic properties and experimental ARPES spectra. We demonstrate its accuracy through circular dichroism ARPES simulations for monolayer graphene and bulk $2H$-WSe$_2$, achieving excellent agreement with experimental data and highlighting the critical role of pseudopotentials in describing high-energy photoelectron scattering. Our results establish a robust and accessible route for quantitative ARPES modeling, paving the way for advanced studies of orbital textures, many-body effects, and time-resolved photoemission.