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arXiv · 2103.17006

Quantum illumination with asymmetrically squeezed two-mode light

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

We propose Gaussian quantum illumination(QI) protocol exploiting asymmetrically squeezed two-mode(ASTM) state that is generated by applying single-mode squeezing operations on each mode of an initial two-mode squeezed vacuum(TMSV) state, in order to overcome the limited brightness of a TMSV state. We show that the performance of the optimal receiver is enhanced by local squeezing operation on a signal mode whereas the performance of a realistic receiver can be enhanced by local squeezing operations on both input modes. Under a fixed mean photon number of the signal mode, the ASTM state can be close to the TMSV state in the performance of QI while there is a threshold of beating classical illumination in the mean photon number of the initial TMSV state. We also verify that quantum discord cannot be a resource of quantum advantage in the Gaussian QI using the ASTM state, which is a counterexample of a previous claim.

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Yonggi Jo, Taek Jeong, Junghyun Kim, Duk Y. Kim, Yong Sup Ihn, Zaeill Kim, Su-Yong Lee. 2021-03-31. Quantum illumination with asymmetrically squeezed two-mode light. https://arxiv.org/abs/2103.17006

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