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arXiv · 2509.22248

Hybrid SU(1,1) interferometry in optomechanics

Chao Meng·Emil Zeuthen·Polina R. Sharapova
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Abstract

In non-degenerate SU(1,1) interferometers, beam splitters are replaced by two-mode squeezers, enabling sub-shot-noise sensitivity without input squeezing and robustness to detection losses by quantum entanglement. We propose a hybrid implementation in optomechanics where one "arm" is a mechanical mode undergoing two consecutive, mode-matched interactions with a traveling optical field (constituting the other arm). Such engineered interactions allow for sub-shot-noise phase detection even in the presence of mechanical thermal noise and optical losses, advancing precision interferometry in hybrid systems.

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Chao Meng, Emil Zeuthen, Polina R. Sharapova. 2025-09-26. Hybrid SU(1,1) interferometry in optomechanics. https://doi.org/10.1103/t9tt-t5x2

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