The Choi–Jamiołkowski isomorphism and covariant quantum channels

  title={The Choi–Jamiołkowski isomorphism and covariant quantum channels},
  author={Erkka Haapasalo},
  journal={Quantum Studies: Mathematics and Foundations},
  • E. Haapasalo
  • Published 27 June 2019
  • Mathematics
  • Quantum Studies: Mathematics and Foundations
A generalization of the Choi-Jamiolkowski isomorphism for completely positive maps between operator algebras is introduced. Particular emphasis is placed on the case of normal unital completely positive maps defined between von Neumann algebras. This generalization is applied especially to the study of maps which are covariant under actions of a symmetry group. We highlight with the example of, e.g., phase-shift-covariant quantum channels the ease of this method in particular in the case of a… 
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