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arXiv · 1707.06926

Gauge invariant information concerning quantum channels

Łukasz Rudnicki·Zbigniew Puchała·Karol Zyczkowski
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Abstract

Motivated by the gate set tomography we study quantum channels from the perspective of information which is invariant with respect to the gauge realized through similarity of matrices representing channel superoperators. We thus use the complex spectrum of the superoperator to provide necessary conditions relevant for complete positivity of qubit channels and to express various metrics such as average gate fidelity.

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Łukasz Rudnicki, Zbigniew Puchała, Karol Zyczkowski. 2018-03-15. Gauge invariant information concerning quantum channels. https://doi.org/10.22331/q-2018-04-11-60

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