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arXiv · 0903.2304

Distinction of Tripartite Greenberger-Horne-Zeilinger and W States Entangled in Time (or Energy) and Space

Jianming Wen·Morton H. Rubin
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Abstract

In tripartite discrete systems, two classes of genuine tripartite entanglement have been discovered, namely, the Greenberger-Horne-Zeilinger (GHZ) class and the W class. To date, much research effort has been concentrated on the polarization entangled three-photon GHZ and W states. Most studies of continuous variable multiparticle entanglement have been focused on Gaussian states. In this Brief Report, we examine two classes of three-photon entangled states in space and time. One class is a three-mode three-photon entangled state and the other is a two-mode triphoton state. These states show behavior similar to the GHZ and W states when one of the photons is not detected. The three-mode entangled state resembles a W state, while a two-mode three-photon state resembles a GHZ state when one of the photons is traced away. We characterize the distinction between these two states by comparing the second-order correlation functions $G^{(2)}$ with the third-order correlation function $G^{(3)}$.

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Jianming Wen, Morton H. Rubin. 2009-03-13. Distinction of Tripartite Greenberger-Horne-Zeilinger and W States Entangled in Time (or Energy) and Space. https://doi.org/10.1103/physreva.79.025802

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