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Enhanced Estimation of a Noisy Quantum Channel Using Entanglement

Dietmar G. Fischer·Holger Mack·Markus A. Cirone·Matthias Freyberger
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Abstract

We discuss the estimation of channel parameters for a noisy quantum channel - the so-called Pauli channel - using finite resources. It turns out that prior entanglement considerably enhances the fidelity of the estimation when we compare it to an estimation scheme based on separable quantum states.

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Dietmar G. Fischer, Holger Mack, Markus A. Cirone, Matthias Freyberger. 2001-03-29. Enhanced Estimation of a Noisy Quantum Channel Using Entanglement. https://doi.org/10.1103/physreva.64.022309

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