Work

Effective Residual Interaction Kernel Approach for Optical Spectra

Year: 2026

Type: article

Abstract: Excitonic effects dominate absorption and loss spectra in many materials. However, they are hard to access computationally, because of the cost of first-principles calculations and because of the scarce reliability of simple approximations. We overcome both limitations by combining a part of the electron-hole Bethe-Salpeter equation with an effective scalar interaction. The partitioning is motivated by the general form of the electron-hole interaction and it can be applied to all materials. First-principles calculations for prototypical semiconductors and insulators demonstrate a speedup of 1 to 2 orders of magnitude for results close to those where the full interaction matrix is used. The method is systematic and can be converged to the benchmark.

Source: Physical Review Letters

DOI: 10.1103/nk3g-crbw

Authors: Marc Aichner, Matteo Gatti, Lucia Reining

Institutions: Centre National de la Recherche Scientifique, École Polytechnique, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, European Theoretical Spectroscopy Facility, Synchrotron SOLEIL

Language: English

Topic: Advanced Chemical Physics Studies

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funder: Agence Nationale de la Recherche

Award: Multimodal approach combining IN-situ, ex-situ and Operando CharacTerizAtion with SimUlations for Highly REliable Next Generation Photovoltaics