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arXiv · 1507.08404

Irreducible decompositions and stationary states of quantum channels

Raffaella Carbone·Yan Pautrat
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Abstract

For a quantum channel (completely positive, trace-preserving map), we prove a generalization to the infinite dimensional case of a result by Baumgartner and Narnhofer. This result is, in a probabilistic language, a decomposition of a general quantum channel into its irreducible positive recurrent components. This decomposition is related with a communication relation on the reference Hilbert space. This allows us to describe the full structure of invariant states of a quantum channel, and of their supports.

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Raffaella Carbone, Yan Pautrat. 2015-07-30. Irreducible decompositions and stationary states of quantum channels. https://doi.org/10.1016/s0034-4877(16)30032-5

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