On Bell measurements for teleportation

N. Lütkenhaus, J. Calsamiglia, K-A. Suominen

Published 1998-09-22, updated 1999-01-28Version 2

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.