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arXiv · 2405.07049

Using non-Gaussian quantum states for detection of a given phase shift

V. L. Gorshenin·F. Ya. Khalili
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Abstract

Injecting a non-Gaussian (Fock or Shr\"odinger cat) quantum state into the dark port of a two-arm interferometer and a strong classical light into the bright one, it is possible, in principle, to detect a given phase shift unambiguously using the orthogonality between the original and displaced in the interferometer non-Gaussian states. The optical losses degrade the sensitivity, introducing the finite "false positive" and "false negative" detection errors. However, using the state-of-art photodetectors, it is still possible to obtain better detection fidelity than in the case of Gaussian quantum states.

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V. L. Gorshenin, F. Ya. Khalili. 2024-05-11. Using non-Gaussian quantum states for detection of a given phase shift. https://arxiv.org/abs/2405.07049

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