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arXiv · 2605.15953

Fast convergence of Dynamic Capacities of GNS-Symmetric Quantum Channels

Omar Fawzi·Li Gao·Mizanur Rahaman·Mostafa Taheri
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Abstract

We consider a quantum system described by a quantum channel $\Phi$ that is applied at every time step and study the time evolution of its information capacities. When $\Phi$ is a GNS-symmetric channel (this includes Pauli channels, for example), we give explicit exponential convergence bounds for the classical and quantum capacities. These bounds are in terms of entropic properties of $\Phi$. We further illustrate how these results help quantify the performance of active versus passive error-correction setups.

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Omar Fawzi, Li Gao, Mizanur Rahaman, Mostafa Taheri. 2026-05-15. Fast convergence of Dynamic Capacities of GNS-Symmetric Quantum Channels. https://arxiv.org/abs/2605.15953

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