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Quantum state engineering assisted by entanglement

Matteo G. A. Paris·Mary Cola·Rodolfo Bonifacio
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Abstract

We suggest a general scheme for quantum state engineering based on conditional measurements carried out on entangled twin-beam of radiation. Realistic detection schemes such as {\sc on/off} photodetection, homodyne detection and joint measurement of two-mode quadratures are analyzed in details. Imperfections of the apparatuses, such as nonunit quantum efficiency and finite resolution, are taken into account. We show that conditional {\sc on/off} photodetection provides a reliable scheme to verify nonclassicality, whereas conditional homodyning represents a tunable and robust source of squeezed light. We also describe optical teleportation as a conditional measurement, and evaluate the degrading effects of finite amount of entanglement, decoherence due to losses, and nonunit quantum efficiency.

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Matteo G. A. Paris, Mary Cola, Rodolfo Bonifacio. 2002-11-20. Quantum state engineering assisted by entanglement. https://doi.org/10.1103/physreva.67.042104

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