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arXiv · 2601.12490

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

Gian Parusa·Sotirios Fragkos·Samuel Beaulieu·Michael Schüler
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Abstract

We introduce an efficient first-principles framework for simulating angle-resolved photoemission spectroscopy (ARPES) based on the direct computation of photoelectron states as solutions of the Kohn-Sham equation with scattering boundary conditions. While the one-step theory of photoemission has a long and successful history, existing implementations are often tied to specialized electronic-structure formalisms. Our approach is formally equivalent to the Lippmann-Schwinger formulation, and it is directly compatible with standard plane-wave and real-space density functional theory codes, enabling seamless integration with advanced exchange-correlation functionals and modern electronic-structure workflows. By providing explicit photoelectron wave functions, the method allows for a transparent analysis of matrix-element effects, multiple scattering, and experimental geometry. We demonstrate the accuracy and predictive power of the framework through circular-dichroism ARPES simulations for monolayer graphene and bulk $2H$-WSe$_2$, achieving excellent agreement with experimental data over a wide photon-energy range. Our results establish a robust and accessible route toward quantitative ARPES modeling, opening the door to systematic studies of orbital textures, many-body effects, and nonequilibrium phenomena within widely used ab initio platforms.

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Gian Parusa, Sotirios Fragkos, Samuel Beaulieu, Michael Schüler. 2026-01-30. Accurate and efficient simulation of photoemission spectroscopy via Kohn-Sham scattering states. https://arxiv.org/abs/2601.12490

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