Geometry of phase-covariant qubit channels

Katarzyna Siudzińska

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arXiv · 2210.17448

Geometry of phase-covariant qubit channels

Katarzyna Siudzińska

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Abstract

We analyze the geometry on the space of non-unital phase-covariant qubit maps. Using the corresponding Choi-Jamio{\l}kowski states, we derive the Hilbert-Schmidt line and volume elements using the channel eigenvalues together with the parameter that characterizes non-unitality. We find the shapes and analytically compute the volumes of phase-covariant channels, in particular entanglement breaking and obtainable with time-local generators.

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Katarzyna Siudzińska. 2022-10-31. Geometry of phase-covariant qubit channels. https://arxiv.org/abs/2210.17448

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