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arXiv:2508.15935 · The Journal of Chemical Physics

Quantum simulation of electron energy loss spectroscopy for battery materials

Alexander A. Kunitsa, Diksha Dhawan, Stepan Fomichev, Juan Miguel Arrazola, Minghao Zhang, Torin F. Stetina

Published Dec 28, 2025• 2 citations
arXivHTMLPDF

Abstract

The dynamic structure factor (DSF) is a central quantity for interpreting a vast array of inelastic scattering experiments in chemistry and materials science, but its accurate simulation poses a considerable challenge for classical computational methods. In this work, we present a quantum algorithm and an end-to-end simulation framework to compute the DSF, providing a general approach for simulating momentum-resolved spectroscopies. We apply this approach to the simulation of electron energy loss spectroscopy (EELS) in the core-level electronic excitation regime, a spectroscopic technique offering sub-nanometer spatial resolution and capable of resolving element-specific information, crucial for analyzing battery materials. We derive a quantum algorithm for computing the DSF for EELS by evaluating the off-diagonal terms of the time-domain Green's function, enabling the simulation of momentum-resolved spectroscopies. To showcase the algorithm, we study the oxygen K-edge EELS spectrum of lithium manganese oxide (Li2MnO3), a prototypical cathode material for investigating the mechanisms of oxygen redox in battery materials. For a representative model of an oxygen-centered cluster of Li2MnO3 with an active space of 18 active orbitals, the algorithm requires a circuit depth of 3.25 × 108 T gates, 100 logical qubits, and roughly 104 shots.

DOI
10.1063/5.0300557

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