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On Bell measurements for teleportation

N. Lütkenhaus·J. Calsamiglia·K-A. Suominen
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Abstract

In this paper we investigate the possibility to make complete Bell measurements on a product Hilbert space of two two-level bosonic systems. We restrict our tools to linear elements, like beam splitters and phase shifters, delay lines and electronically switched linear elements, photo-detectors, and auxiliary bosons. As a result we show that with these tools a never failing Bell measurement is impossible.

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N. Lütkenhaus, J. Calsamiglia, K-A. Suominen. 1998-09-22. On Bell measurements for teleportation. https://doi.org/10.1103/physreva.59.3295

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