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arXiv · 1608.06221

Quantum channel-estimation with particle loss: GHZ versus W states

Julien Mathieu Elias Fraïsse·Daniel Braun
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Abstract

We consider quantum channel-estimation for depolarizing channels and phase-flip channels extended by ancilla qubits and fed with a GHZ or W state. After application of the channel one or several qubits can be lost, and we calculate the impact of the loss on the quantum Fisher information that determines the smallest uncertainty with which the parameters of these channels can be estimated.

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Julien Mathieu Elias Fraïsse, Daniel Braun. 2016-08-22. Quantum channel-estimation with particle loss: GHZ versus W states. https://doi.org/10.1515/qmetro-2016-0009

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