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arXiv · 1702.06287

Demonstration of monogamy relations for Einstein-Podolsky-Rosen steering in Gaussian cluster states

Xiaowei Deng·Yu Xiang·Caixing Tian·Gerardo Adesso·Qiongyi He·Qihuang Gong·Xiaolong Su·Changde Xie·Kunchi Peng
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Abstract

Understanding how quantum resources can be quantified and distributed over many parties has profound applications in quantum communication. As one of the most intriguing features of quantum mechanics, Einstein-Podolsky-Rosen (EPR) steering is a useful resource for secure quantum networks. By reconstructing the covariance matrix of a continuous variable four-mode square Gaussian cluster state subject to asymmetric loss, we quantify the amount of bipartite steering with a variable number of modes per party, and verify recently introduced monogamy relations for Gaussian steerability, which establish quantitative constraints on the security of information shared among different parties. We observe a very rich structure for the steering distribution, and demonstrate one-way EPR steering of the cluster state under Gaussian measurements, as well as one-to-multi-mode steering. Our experiment paves the way for exploiting EPR steering in Gaussian cluster states as a valuable resource for multiparty quantum information tasks.

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Xiaowei Deng, Yu Xiang, Caixing Tian, Gerardo Adesso, Qiongyi He, Qihuang Gong, Xiaolong Su, Changde Xie, Kunchi Peng. 2017-06-10. Demonstration of monogamy relations for Einstein-Podolsky-Rosen steering in Gaussian cluster states. https://doi.org/10.1103/physrevlett.118.230501

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