Device-independent state estimation based on Bell’s inequalities

  title={Device-independent state estimation based on Bell’s inequalities},
  author={Charles-Edouard Bardyn and Timothy C. H. Liew and Serge Massar and Matthew Mckague and Valerio Scarani},
  journal={Physical Review A},
The only information available about an alleged source of entangled quantum states is the amount S by which the Clauser-Horne-Shimony-Holt inequality is violated: nothing is known about the nature of the system or the measurements that are performed. We discuss how the quality of the source can be assessed in this black-box scenario, as compared to an ideal source that would produce maximally entangled states (more precisely, any state for which S=2 root 2). To this end, we present several… 

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