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arXiv · 2605.02981

Self-consistent radiative backaction in dispersion interactions: a minimal mQED model

Johannes Fiedler
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Abstract

Dispersion interactions are usually derived assuming fixed internal spectra of the interacting quantum systems. Here, we relax this assumption and study how self-consistent electromagnetic backaction modifies van der Waals interactions when excitation energies and transition dipole moments are allowed to respond to the interaction itself. Within a macroscopic quantum electrodynamics framework, we formulate a self-consistent treatment that includes both self-energy corrections and mutual backaction. Using a minimal three-level model, we show that, while one-sided self-energy effects are short-ranged, fully self-consistent backaction can lead to substantial, long-ranged modifications of the effective van der Waals interaction. Our analysis demonstrates that these effects originate from the coherent accumulation of repeated photon-mediated scattering processes. The results highlight limitations of perturbative dispersion theories with fixed spectra and identify few-level systems as a clean platform for studying backaction in dispersion forces.

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Johannes Fiedler. 2026-05-04. Self-consistent radiative backaction in dispersion interactions: a minimal mQED model. https://arxiv.org/abs/2605.02981

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