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  • Open Access

Entanglement harvesting in the presence of cavities

Jannik Ströhle* and Nikolija Momčilović

  • Institut für Quantenphysik and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Albert-Einstein-Allee 11, D-89069 Ulm, Germany

  • *Contact author: jannik.stroehle@uni-ulm.de
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Phys. Rev. Research 8, 023198 – Published 21 May, 2026

DOI: https://doi.org/10.1103/ltdq-y4mf

Abstract

So far, entanglement harvesting has been extensively studied in free-space setups. Here, we provide a detailed analytical and numerical analysis of entanglement harvesting in cavities. Specifically, we couple the quantized electromagnetic field to two identical Gaussian detectors located on the symmetry axis of a cylindrical cavity via Gaussian switching. Our numerical investigations reveal a strong dependence on the cavity length, while showing invariance under changes in the cavity radius in regimes of maximal entanglement. Moreover, we identify different scalings of the detector system parameters for entanglement inside and outside the light cone. Finally, we uncover a strong dependence of the harvested correlations on the cavity-induced parity of the electromagnetic field.

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Phys. Rev. Research 8, 023198– Published 21 May, 2026
  • Received 23 November 2025
  • Accepted 22 April 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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