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Continuous-variable teleportation in the characteristic-function description

Paulina Marian·Tudor A. Marian
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Abstract

We give a description of the continuous-variable teleportation protocol in terms of the characteristic functions of the quantum states involved. The Braunstein--Kimble protocol is written for an unbalanced homodyne measurement and arbitrary input and resource states. We show that the output of the protocol is a superposition between the input one-mode field and a classical one induced by measurement and classical communication. We choose to describe the input state distortion through teleportation by the average photon number of the measurement-induced field. Only in the case of symmetric resource states we find a relation between the optimal added noise and the minimal EPR correlations used to define inseparability.

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Paulina Marian, Tudor A. Marian. 2006-09-26. Continuous-variable teleportation in the characteristic-function description. https://doi.org/10.1103/physreva.74.042306

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