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arXiv · 2201.03258

Measure of invertible dynamical maps under convex combinations of noninvertible dynamical maps

Vinayak Jagadish·R. Srikanth·Francesco Petruccione
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Abstract

We study the convex combinations of the $(d+1)$ generalized Pauli dynamical maps in a Hilbert space of dimension $d$. For certain choices of the decoherence function, the maps are noninvertible and they remain under convex combinations as well. For the case of dynamical maps characterized by the decoherence function $(1-e^{-ct})/n$ with the decoherence parameter $n$ and decay factor $c$, we evaluate the fraction of invertible maps obtained upon mixing, which is found to increase superexponentially with dimension $d$.

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Vinayak Jagadish, R. Srikanth, Francesco Petruccione. 2022-01-10. Measure of invertible dynamical maps under convex combinations of noninvertible dynamical maps. https://doi.org/10.1103/physreva.106.012438

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