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Continuous-variable teleportation improvement by photon subtraction via conditional measurement

T. Opatrny·G. Kurizki·D. -G. Welsch
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Abstract

We show that the recently proposed scheme of teleportation of continuous variables [S.L. Braunstein and H.J. Kimble, Phys. Rev. Lett. 80, 869 (1998)] can be improved by a conditional measurement in the preparation of the entangled state shared by the sender and the recipient. The conditional measurement subtracts photons from the original entangled two-mode squeezed vacuum, by transmitting each mode through a low-reflectivity beam splitter and performing a joint photon-number measurement on the reflected beams. In this way the degree of entanglement of the shared state is increased and so is the fidelity of the teleported state.

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T. Opatrny, G. Kurizki, D. -G. Welsch. 1999-07-13. Continuous-variable teleportation improvement by photon subtraction via conditional measurement. https://doi.org/10.1103/physreva.61.032302

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