Closing the detection loophole in multipartite Bell tests using Greenberger-Horne-Zeilinger states

Károly F. Pál, Tamás Vértesi, Nicolas Brunner
2012 Physical Review A. Atomic, Molecular, and Optical Physics  
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 n-qubit Greenberger-Horne-Zeilinger states, which can tolerate efficiencies as low as 38% for a reasonable number of parties and measurements. Even in the presence of a significant amount of noise, efficiencies below 50% can be tolerated, which is
more » ... ted, 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.
doi:10.1103/physreva.86.062111 fatcat:53xz5tmcvvhsdiavppc2b6xwou