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arXiv · 2301.04396

Matters Arising: Entanglement-enhanced matter-wave interferometry in a high-finesse cavity

Liam P. McGuinness
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Abstract

In their paper "Entanglement-enhanced matter-wave interferometry in a high-finesse cavity" Nature (2022), Greve et. al. claim to use entanglement in a matter-wave interferometer to achieve a sensitivity beyond that achievable with the same number of independent particles -- a limit known as the standard quantum limit (SQL). In particular, using squeezed momentum states of 700 atoms, the authors claim to directly observe a sensitivity 3.4 dB (a factor of 1.5) below the SQL. This claim is incorrect. The authors do not measure anything beyond the SQL, nor do they achieve a sensitivity beyond what one could obtain with a single atom. The achieved sensitivity is at least a factor of 39 worse than the claimed value.

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Liam P. McGuinness. 2023-01-11. Matters Arising: Entanglement-enhanced matter-wave interferometry in a high-finesse cavity. https://arxiv.org/abs/2301.04396

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