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Notes on optimality of direct characterisation of quantum dynamics

Mario Ziman
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Abstract

We argue that the claimed optimality of a new process tomography method suggested in [quant-ph/0601033] and [quant-ph/0601034] is based on not completely fair comparison that does not take into account the available information in an equal way. We also argue that the method is not a new process tomography scheme, but rather represents an interesting modification of ancilla assisted process tomography method. In our opinion these modifications require deeper understanding and further investigation.

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Mario Ziman. 2006-03-17. Notes on optimality of direct characterisation of quantum dynamics. https://arxiv.org/abs/quant-ph/0603151

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