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Bose Polarons as Relativistic Unruh-DeWitt Detectors: Entanglement Harvesting from Bose-Einstein Condensates

T. Rick Perche1, Francesco Gozzini2, and Markus K. Oberthaler2,*

  • *Contact author: unruh-dewitt-detector@matterwave.de
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Phys. Rev. Lett. 137, 170401 – Published 20 October, 2026

DOI: https://doi.org/10.1103/54t2-pmf8

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 K41 impurities coupled to a Rb87 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.

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Phys. Rev. Lett. 137, 170401– Published 20 October, 2026
  • Received 31 January 2026
  • Revised 16 September 2026
  • Accepted 24 September 2026
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