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arXiv · 1901.06858

Retrieving ideal precision in noisy quantum optical metrology

Kai Bai·Zhen Peng·Hong-Gang Luo·Jun-Hong An
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Abstract

Quantum metrology employs quantum effects to attain a measurement precision surpassing the limit achievable in classical physics. However, it was previously found that the precision returns the shot-noise limit (SNL) from the ideal Zeno limit (ZL) due to the photon loss in quantum metrology based on Mech-Zehnder interferometer. Here, we find that not only the SNL can be beaten, but also the ZL can be asymptotically recovered in long-encoding-time condition when the photon dissipation is exactly studied in its inherent non-Markovian manner. Our analysis reveals that it is due to the formation of a bound state of the photonic system and its dissipative noise. Highlighting the microscopic mechanism of the dissipative noise on the quantum optical metrology, our result supplies a guideline to realize the ultrasensitive measurement in practice by forming the bound state in the setting of reservoir engineering.

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Kai Bai, Zhen Peng, Hong-Gang Luo, Jun-Hong An. 2019-01-21. Retrieving ideal precision in noisy quantum optical metrology. https://doi.org/10.1103/physrevlett.123.040402

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