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arXiv · 2312.14443

Time-reversal assisted quantum metrology with an optimal control

Da-Wei Luo·Ting Yu
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Abstract

We propose a protocol to overcome the shot noise limit and reach the Heisenberg scaling limit for parameter estimation by using quantum optimal control and a time-reversal strategy. Exemplified through the phase estimation, which can play an important role in quantum navigation and measurement, we show that the uncertainty arising from a photon number measurement of the system can saturate the assisted Cream\'er-Rao bound, independent of the phase being estimated. In a realistic case with photon loss, we show that the optimal estimation may still be attainable by optimal control and a projective measurement on an ancilla two-level system coupled to photonic modes.

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Da-Wei Luo, Ting Yu. 2023-12-22. Time-reversal assisted quantum metrology with an optimal control. https://arxiv.org/abs/2312.14443

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