English

3/4-efficient Bell measurement with passive linear optics and unentangled ancillae

Quantum Physics 2014-10-08 v1

Abstract

It is well known that an unambiguous discrimination of the four optically encoded Bell states is possible with a probability of 50%50\% at best, when using static, passive linear optics and arbitrarily many vacuum mode ancillae. By adding unentangled single-photon ancillae, we are able to surpass this limit and reach a success probability of at least 75%75\%. We discuss the error robustness of the proposed scheme and a generalization to reach a success probability arbitrarily close to 100%100\%.

Cite

@article{arxiv.1403.4841,
  title  = {3/4-efficient Bell measurement with passive linear optics and unentangled ancillae},
  author = {Fabian Ewert and Peter van Loock},
  journal= {arXiv preprint arXiv:1403.4841},
  year   = {2014}
}

Comments

5+3 pages, 2 figures. Comments are welcome!

R2 v1 2026-06-22T03:30:00.918Z