Abstract
We investigate the problem of closing the detection loophole in multipartite Bell tests, and show that the required detection efficiencies can be significantly lowered compared to the bipartite case. In particular, we present Bell tests based on -qubit Greenberger-Horne-Zeilinger states, which can tolerate efficiencies as low as for a reasonable number of parties and measurements. Even in the presence of a significant amount of noise, efficiencies below can be tolerated, which is encouraging given recent experimental progress. Finally, we give strong evidence that, for a sufficiently large number of parties and measurements, arbitrarily small efficiencies can be tolerated, even in the presence of an arbitrary large amount of noise.
- Received 7 August 2012
DOI:https://doi.org/10.1103/PhysRevA.86.062111
©2012 American Physical Society