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arXiv · 2504.11226

Ab initio Maxwell-Bloch Approach for X-Ray Excitations in Two-Dimensional Materials

Joris Sturm·Ivan Maliyov·Dominik Christiansen·Malte Selig·Marco Bernardi·Andreas Knorr
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Abstract

The combination of Maxwell and X-ray Bloch equations forms an appropriate framework to describe ultrafast time-resolved X-ray experiments on attosecond time scale in crystalline solids. However, broadband experiments such as X-ray absorption near edge spectroscopy or resonant inelastic X-ray scattering require a detailed knowledge of the electronic structure and transition matrix elements. Here, we show how to fill this gap by combining the Maxwell-X-ray Bloch formalism with first-principles calculations treating explicitly the core states. The resulting X-ray absorption spectrum recovers key spectral signatures which were missing in our previous work relying on a semi-empirical tight-binding approach.

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Joris Sturm, Ivan Maliyov, Dominik Christiansen, Malte Selig, Marco Bernardi, Andreas Knorr. 2025-04-15. Ab initio Maxwell-Bloch Approach for X-Ray Excitations in Two-Dimensional Materials. https://arxiv.org/abs/2504.11226

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