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Extremal Channels for a genaral Quantum system

Quantum Physics 2009-09-22 v1

Abstract

Quantum channels can be mathematically represented as completely positive trace-preserving maps that act on a density matrix. A general quantum channel can be written as a convex sum of `extremal' channels. We show that for an NN-level system, the extremal channel can be characterized in terms of N2N^2-NN real parameters coupled with rotations. We give a representation for NN= 2, 3, 4.

Keywords

Cite

@article{arxiv.0909.3744,
  title  = {Extremal Channels for a genaral Quantum system},
  author = {Kuldeep Dixit and E. C. G. Sudarshan},
  journal= {arXiv preprint arXiv:0909.3744},
  year   = {2009}
}

Comments

3 pages, 1 figure

R2 v1 2026-06-21T13:48:37.179Z