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arXiv · 2205.05808

Pauli component erasing quantum channels

Jose Alfredo de Leon·Alejandro Fonseca·Francois Leyvraz·David Davalos·Carlos Pineda
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Abstract

Decoherence of quantum systems is described by quantum channels. However, a complete understanding of such channels, especially in the multi-particle setting, is still an ongoing difficult task. We propose the family of quantum maps that preserve or completely erase the components of a multi-qubit system in the basis of Pauli strings, which we call Pauli component erasing maps. For the corresponding channels, it is shown that the preserved components can be interpreted as a finite vector subspace, from which we derive several properties and complete the characterization. Moreover, we show that the obtained family of channels forms a semigroup and derive its generators. We use this simple structure to determine physical implementations and connect the obtained family of channels with Markovian processes.

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Jose Alfredo de Leon, Alejandro Fonseca, Francois Leyvraz, David Davalos, Carlos Pineda. 2022-05-12. Pauli component erasing quantum channels. https://doi.org/10.1103/physreva.106.042604

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