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arXiv · 2206.06233

QED approach to valence-hole excitation in closed shell systems

R. N. Soguel·A. V. Volotka·S. Fritzsche
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Abstract

An ab initio QED approach to treat a valence-hole excitation in closed shell systems is developed in the framework of the two-time-Green function method. The derivation considers a redefinition of the vacuum state and its excitation as a valence-hole pair. The proper two-time Green function, whose spectral representation confirms the poles at valence-hole excitation energies is proposed. An contour integral formula which connects the energy corrections and the Green function is also presented. First-order corrections to the valence-hole excitation energy involving self-energy, vacuum polarization, and one-photon-exchange terms are explicitly derived in the redefined vacuum picture. Reduction to the usual vacuum electron propagators is given that agrees in the Breit approximation with the many-body perturbation theory expressions for the valence-hole excitation energy.

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R. N. Soguel, A. V. Volotka, S. Fritzsche. 2022-06-13. QED approach to valence-hole excitation in closed shell systems. https://doi.org/10.1103/physreva.106.012802

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