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arXiv:2604.06303 · Physical review. D/Physical review. D.

Optimization of entanglement harvesting with arbitrary temporal profiles: the limit of second order perturbation theory

Marcos Morote-Balboa, T. Rick Perche

quant-phgr-qchep-thSubmitted Apr 7, 2026• Announced Apr 9, 2026• 0 citations• Revised Oct 29, 2026 (v4)
v1 · Apr 7, 2026v2 · Apr 29, 2026v3 · Jul 23, 2026v4 · Oct 29, 2026
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Abstract

We study the protocol of entanglement harvesting when two local probes couple to the vacuum of a real scalar quantum field with arbitrary temporal profiles. We use a Hermite expansion to efficiently compute smeared field propagators in closed-form, recasting the negativity between the probes as a matrix product. We then optimize the protocol under different signalling conditions, enhancing entanglement harvesting by several orders of magnitude. This optimization would take current experimental proposals beyond the regime of second order perturbation theory.

Journal reference
Phys. Rev. D 114, 085027 (2026)
DOI
10.1103/kq6r-ryl7
Comments
12 pages, 8 figures + appendices, v2 added Entanglement Harvesting Exproler tool (https://entanglement-harvesting-explorer.streamlit.app/)

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