The information capacity of entanglement-assisted continuous variable quantum measurement

  title={The information capacity of entanglement-assisted continuous variable quantum measurement},
  author={Alexander S. Holevo and Anastasia A. Kuznetsova},
  journal={Journal of Physics A: Mathematical and Theoretical},
  • A. Holevo, A. A. Kuznetsova
  • Published 11 April 2020
  • Physics, Computer Science
  • Journal of Physics A: Mathematical and Theoretical
The present paper is devoted to the investigation of the entropy reduction and entanglement-assisted classical capacity (information gain) of continuous variable quantum measurements. These quantities are computed explicitly for multimode Gaussian measurement channels. For this we establish a fundamental property of the entropy reduction of a measurement: under a restriction on the second moments of the input state it is maximized by a Gaussian state (providing an analytical expression for the… 
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