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Scheme for conditional generation of photon-added coherent state and optical entangled $W$ state

Yan Li·Hui Jing·Ming-Sheng Zhan
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Abstract

We propose a simple scheme to generate an arbitrary photon-added coherent state of a travelling optical field by using only a set of degenerate parametric amplifiers and single-photon detectors. Particularly, when the single-photon-added coherent state (SPACS) is observed by following, e.g., the novel technique of Zavatta \emph{$et al.$} (Science 306, 660 (2004)), we also obtain the generalized optical entangled $W$ state. Finally, a qualitative analysis of possible losses in our scheme is given.

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Yan Li, Hui Jing, Ming-Sheng Zhan. 2006-10-17. Scheme for conditional generation of photon-added coherent state and optical entangled $W$ state. https://arxiv.org/abs/quant-ph/0610143

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