Quantum algorithm for Petz recovery channels and pretty good measurements

  title={Quantum algorithm for Petz recovery channels and pretty good measurements},
  author={Andr'as Gily'en and Seth Lloyd and Iman Marvian and Yihui Quek and Mark M. Wilde},
  journal={Physical review letters},
  volume={128 22},
The Petz recovery channel plays an important role in quantum information science as an operation that approximately reverses the effect of a quantum channel. The pretty good measurement is a special case of the Petz recovery channel, and it allows for near-optimal state discrimination. A hurdle to the experimental realization of these vaunted theoretical tools is the lack of a systematic and efficient method to implement them. This Letter sets out to rectify this lack: Using the recently… 

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