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arXiv · 0909.3744

Extremal Channels for a genaral Quantum system

Kuldeep Dixit·E. C. G. Sudarshan
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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 $N$-level system, the extremal channel can be characterized in terms of $N^2$-$N$ real parameters coupled with rotations. We give a representation for $N$= 2, 3, 4.

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Kuldeep Dixit, E. C. G. Sudarshan. 2009-09-21. Extremal Channels for a genaral Quantum system. https://arxiv.org/abs/0909.3744

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