Auger Spectroscopy via Generative Quantum Eigensolver: A Quantum Approach to Molecular Excitations

Quantum Physics [Submitted on 13 Mar 2026] Auger Spectroscopy via Generative Quantum Eigensolver: A Quantum Approach to Molecular Excitations Kimberlee Keithley, Shunsuke Yamamoto, Ryota Kenmoku, Ikko Hamamura, Kouhei Nakaji, Shu Kanno, Takao Kobayashi, Qi Gao, Shumpei Uno, Kohei Oshio, Naoki Watanabe, Takeshi Sato, Naoki Yamamoto, Shunya Minami, Yohichi Suzuki, Yuma Nakamura, Jorge A. Campos-Gonzalez-Angulo, Mohammad Ghazi Vakili, Alan Aspuru-Guzik Auger electron spectroscopy, a way of characterizing electronic structure through core-level decay processes, is widely used in materials characterization; however direct calculation from molecular geometry requires accurate treatment of many excited states, posing a challenge for classical methods. We present a hybrid quantum-classical workflow for calculating Auger spectra that combines the generative quantum eigensolver (GQE) for ground-state preparation, the quantum self-consistent equation-of-motion method for excited-state calculations, and the one-centre approximation for Auger transition rates. GQE uses a GPT-2 model to generate quantum circuits for ground-state optimization, allowing our workflow to benefit from HPC parallelization and GPU-acceleration for favourable scaling with system size. We demonstrate the validity of our workflow by calculating the Auger spectrum of water with the STO-3G basis set and demonstrating qualitative and quantitative agreement with spectra obtained using completely classical full configuration interaction calculations, from the computational literature, and from the experimental literature. We also find that for water, substituting the variational quantum eigensolver (VQE) for GQE results in near-identical spectra, but that the ground state estimator generated by GQE contains about half the total gate count as that generated by VQE. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2603.12859 [quant-ph]   (or arXiv:2603.12859v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2603.12859 Focus to learn more Submission history From: Kimberlee Keithley [view email] [v1] Fri, 13 Mar 2026 10:03:39 UTC (336 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-03 References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)