Closing the detection loophole in Bell experiments using qudits.

  title={Closing the detection loophole in Bell experiments using qudits.},
  author={Tam{\'a}s V{\'e}rtesi and Stefano Pironio and Nicolas Brunner},
  journal={Physical review letters},
  volume={104 6},
We show that the detection efficiencies required for closing the detection loophole in Bell tests can be significantly lowered using quantum systems of dimension larger than two. We introduce a series of asymmetric Bell tests for which an efficiency arbitrarily close to 1/N can be tolerated using N-dimensional systems, and a symmetric Bell test for which the efficiency can be lowered down to 61.8% using four-dimensional systems. Experimental perspectives for our schemes look promising… 

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