Vacuum entanglement probes for ultra-cold atom systems

TL;DR

This paper investigates how nonclassical correlations in ultra-cold atom systems can be transferred to laser beams using nondestructive measurements, aiming to enable entanglement harvesting in quantum simulations.

Contribution

It establishes a mathematical equivalence between laser probe interactions and entanglement harvesting protocols, and analyzes experimental challenges in ultra-cold atom systems.

Findings

Mathematical equivalence demonstrated between probes and entanglement harvesting

Potential for nondestructive entanglement detection in BECs

Identified obstacles for experimental realization

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, using lasers as Unruh-DeWitt detectors for phonons. The 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.