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arXiv · 2004.09234

Quantum illumination via quantum-enhanced sensing

Su-Yong Lee·Yong Sup Ihn·Zaeill Kim
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Abstract

Quantum-enhanced sensing has a goal of enhancing a parameter sensitivity with input quantum states, while quantum illumination has a goal of enhancing a target detection capability with input entangled states in a heavy noise environment. Here we propose a concatenation between quantum-enhanced sensing and quantum illumination that can take quantum advantage over the classical limit. First, phase sensing in an interferometry is connected to a target sensing via quantum Fisher information. Second, the target sensitivity is investigated in noisy quantum-enhanced sensing. Under the same input state energy, for example, N-photon entangled states can exhibit better performance than a two-mode squeezed vacuum state and a separable coherent state. Incorporating a photon-number difference measurement, finally, the noisy target sensitivity is connected to a signal-to-noise ratio which is associated with a minimum error probability of discriminating the presence and absence of the target. We show that both the target sensitivity and the signal-to-noise ratio can be enhanced with increasing thermal noise.

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Su-Yong Lee, Yong Sup Ihn, Zaeill Kim. 2021-01-20. Quantum illumination via quantum-enhanced sensing. https://doi.org/10.1103/physreva.103.012411

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