Certifiability criterion for large-scale quantum systems

  title={Certifiability criterion for large-scale quantum systems},
  author={Florian Frowis and Maarten Van den Nest and Wolfgang Dur},
  journal={New Journal of Physics},
Can one certify the preparation of a coherent, many-body quantum state by measurements with bounded accuracy in the presence of noise and decoherence? Here, we introduce a criterion to assess the fragility of large-scale quantum states, which is based on the distinguishability of orthogonal states after the action of very small amounts of noise. States which do not pass this criterion are called asymptotically incertifiable. We show that if a coherent quantum state is asymptotically… 

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