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arXiv · 2605.21595

Testing Superpositions of Detector Trajectories

Cisco Gooding·Taylor Cey·Robert Mann
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Abstract

We propose a realizable experiment to test the response of a particle detector prepared in a superposition of locations interacting with a relativistic quantum field. Using a beamsplitter to prepare two superposed branches of a modulated laser probe, these branches are directed to intersect a pancake-shaped Bose-Einstein condensate at two separate locations. The branches are then recombined with another beamsplitter. Heterodyning one of the outputs, the response function corresponding to an Unruh-deWitt detector in a superposition of locations interacting with a (2+1)-dimensional massless scalar field is shown to appear in the difference photocurrent power spectrum. Operating beyond the standard quantum limit using squeezed light, we estimate the signal-to-noise ratio $SNR\gtrsim 10$ for extracting the response function over a broad set of baseband frequencies.

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Cisco Gooding, Taylor Cey, Robert Mann. 2026-05-20. Testing Superpositions of Detector Trajectories. https://arxiv.org/abs/2605.21595

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