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arXiv:2512.21381 · Physical Review Letters

Bose polarons as relativistic Unruh-DeWitt detectors: Entanglement harvesting from Bose-Einstein condensates

T. Rick Perche, Francesco Gozzini, Markus K. Oberthaler

quant-phcond-mat.quant-gashep-thSubmitted Dec 24, 2025• Announced Dec 26, 2025• 0 citations• Revised Jun 30, 2026 (v3)
v1 · Dec 24, 2025v2 · Feb 2, 2026v3 · Jun 30, 2026
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Abstract

We show that a bound impurity in a Bose-Einstein condensate can be directly mapped to an Unruh-DeWitt detector interacting with a relativistic quantum field. We provide explicit experimental parameters for an implementation using ${}^{41}\text{K}$ impurities coupled to a ${}^{87}\text{Rb}$ condensate via finite-time Feshbach tuning. As an application, we study the extraction of vacuum entanglement from distant regions of the condensate and find viable parameters for the implementation of entanglement harvesting.

Comments
5 pages, 3 figures + appendices

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