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تسجيل مستخدم جديدUnity gain and non-unity gain quantum teleportation
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We investigate continuous variable quantum teleportation. We discuss the methods presently used to characterize teleportation in this regime, and propose an extension of the measures proposed by Grangier and Grosshans cite{Grangier00}, and Ralph and Lam cite{Ralph98}. This new measure, the gain normalized conditional variance product $mathcal{M}$, turns out to be highly significant for continuous variable entanglement swapping procedures, which we examine using a necessary and sufficient criterion for entanglement. We elaborate on our recent experimental continuous variable quantum teleportation results cite{Bowen03}, demonstrating success over a wide range of teleportation gains. We analyze our results using fidelity; signal transfer, and the conditional variance product; and a measure derived in this paper, the gain normalized conditional variance product.
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