Private quantum codes: introduction and connection with higher rank numerical ranges

  title={Private quantum codes: introduction and connection with higher rank numerical ranges},
  author={David W. Kribs and Sarah Plosker},
  journal={Linear and Multilinear Algebra},
  pages={639 - 647}
  • D. KribsS. Plosker
  • Published 31 March 2014
  • Computer Science, Mathematics
  • Linear and Multilinear Algebra
We give a brief introduction to private quantum codes, a basic notion in quantum cryptography and key distribution. Private code states are characterized by indistinguishability of their output states under the action of a quantum channel, and we show that higher rank numerical ranges can be used to describe them. We also show how this description arises naturally via conjugate channels and the bridge between quantum error correction and cryptography. 
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