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arXiv · 2204.11552

Experimental demonstration of remotely creating Wigner negativity via quantum steering

Abstract

Non-Gaussian states with Wigner negativity are of particular interest in quantum technology due to their potential applications in quantum computing and quantum metrology. However, how to create such states at a remote location remains a challenge, which is important for efficiently distributing quantum resource between distant nodes in a network. Here, we experimentally prepare optical non-Gaussian state with negative Wigner function at a remote node via local non-Gaussian operation and shared Gaussian entangled state existing quantum steering. By performing photon subtraction on one mode, Wigner negativity is created in the remote target mode. We show that the Wigner negativity is sensitive to loss on the target mode, but robust to loss on the mode performing photon subtraction. This experiment confirms the connection between the remotely created Wigner negativity and quantum steering. As an application, we present that the generated non-Gaussian state exhibits metrological power in quantum phase estimation.

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Shuheng Liu, Dongmei Han, Na Wang, Yu Xiang, Fengxiao Sun, Meihong Wang, Zhongzhong Qin, Qihuang Gong, Xiaolong Su, Qiongyi He. 2022-04-25. Experimental demonstration of remotely creating Wigner negativity via quantum steering. https://doi.org/10.1103/physrevlett.128.200401

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