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arXiv · 1909.05509

Einstein-Podolsky-Rosen steering in Gaussian weighted graph states

Meihong Wang·Xiaowei Deng·Zhongzhong Qin·Xiaolong Su
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Abstract

Einstein-Podolsky-Rosen (EPR) steering, as one of the most intriguing phenomenon of quantum mechanics, is a useful quantum resource for quantum communication. Understanding the type of EPR steering in a graph state is the basis for application of it in a quantum network. In this paper, we present EPR steering in a Gaussian weighted graph state, including a linear tripartite and a four-mode square weighted graph state. The dependence of EPR steering on weight factor in the weighted graph state is analyzed. Gaussian EPR steering between two modes of a weighted graph state is presented, which does not exist in the Gaussian cluster state (where the weight factor is unit). For the four-mode square Gaussian weighted graph state, EPR steering between one and its two nearest modes is also presented, which is absent in the four-mode square Gaussian cluster state. We also show that Gaussian EPR steering in a weighted graph state is also bounded by the Coffman-Kundu-Wootters monogamy relation. The presented results are useful for exploiting EPR steering in a Gaussian weighted graph state as a valuable resource in multiparty quantum communication tasks.

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Meihong Wang, Xiaowei Deng, Zhongzhong Qin, Xiaolong Su. 2019-09-12. Einstein-Podolsky-Rosen steering in Gaussian weighted graph states. https://doi.org/10.1103/physreva.100.022325

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