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arXiv · 2106.12109

Observable bound for Gaussian illumination

Su-Yong Lee·Yonggi Jo·Taek Jeong·Junghyun Kim·Dong Hwan Kim·Dongkyu Kim·Duk Y. Kim·Yong Sup Ihn·Zaeill Kim
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Abstract

We propose observable bounds for Gaussian illumination to maximize the signal-to-noise ratio, which minimizes the discrimination error between the presence and absence of a low-reflectivity target using Gaussian states. The observable bounds are achieved with mode-by-mode measurements. In the quantum regime using a two-mode squeezed vacuum state, our observable receiver outperforms the other feasible receivers whereas it cannot approach the quantum Chernoff bound. The corresponding observable cannot be implemented with heterodyne detections due to the additional vacuum noise. In the classical regime using a thermal state, a receiver implemented with a photon number difference measurement approaches its bound regardless of the signal mean photon number, while it asymptotically approaches the classical bound in the limit of a huge idler mean photon number.

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Su-Yong Lee, Yonggi Jo, Taek Jeong, Junghyun Kim, Dong Hwan Kim, Dongkyu Kim, Duk Y. Kim, Yong Sup Ihn, Zaeill Kim. 2021-06-23. Observable bound for Gaussian illumination. https://doi.org/10.1103/physreva.105.042412

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