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arXiv · 1106.1536

Multipartite continuous-variable entanglement distillation using local squeezing and only one photon-subtraction operation

Song Yang·XuBo Zou·ShengLi Zhang·Bao-Sen Shi·Peter van Loock·GuangCan Guo
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Abstract

In this paper, we study entanglement distillation of multipartite continuous-variable Gaussian entangled states. Following Opatrný \emph{et al.}'s photon subtraction (PS) scheme, the probability of successful distillation decreases exponentially with the number of parties $N$. However, here, we shall propose an entanglement distillation scheme whose success probability scales as a constant with $N$. Our protocol employs several local squeezers, but it requires only a single PS operation. Using the logarithmic negativity as a measure of entanglement, we find that both the success probability and the distilled entanglement can be improved at the same time. Moreover, an $N$-mode transfer theorem (transferring states from phase space to Hilbert space) is presented.

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Song Yang, XuBo Zou, ShengLi Zhang, Bao-Sen Shi, Peter van Loock, GuangCan Guo. 2011-06-08. Multipartite continuous-variable entanglement distillation using local squeezing and only one photon-subtraction operation. https://arxiv.org/abs/1106.1536

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