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arXiv · 2308.07892

Vacuum entanglement probes for ultra-cold atom systems

Cisco Gooding·Allison Sachs·Robert B. Mann·Silke Weinfurtner
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Abstract

This study explores the transfer of nonclassical correlations from an ultra-cold atom system to a pair of pulsed laser beams. Through nondestructive local probe measurements, we introduce an alternative to destructive techniques for mapping BEC entanglement. Operating at ultralow temperatures, the setup emulates a relativistic vacuum field. We show that lasers can serve as Unruh-DeWitt detectors for BEC vacuum phonons. A quantum vacuum holds intrinsic entanglement, transferable to distant probes briefly interacting with it - a phenomenon termed `entanglement harvesting'. Our study accomplishes two primary objectives: first, establishing a mathematical equivalence between a pair of pulsed laser probes interacting with an effective relativistic field and the entanglement harvesting protocol; and second, to closely examine the potential and persisting obstacles for realising this protocol in an ultra-cold atom experiment.

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Cisco Gooding, Allison Sachs, Robert B. Mann, Silke Weinfurtner. 2023-08-15. Vacuum entanglement probes for ultra-cold atom systems. https://doi.org/10.1088/1367-2630%2Fad8675

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