Two-setting Bell inequalities for graph states

  title={Two-setting Bell inequalities for graph states},
  author={G{\'e}za T{\'o}th and Otfried Guehne and Hans J. Briegel},
  journal={Physical Review A},
We present Bell inequalities for graph states with a high violation of local realism. In particular, we show that there is a basic Bell inequality for every nontrivial graph state which is violated by the state at least by a factor of 2. This inequality needs the measurement of, at most, two operators for each qubit and involves only some of the qubits. We also show that for some families of graph states composite Bell inequalities can be constructed such that the violation of local realism… 

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