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arXiv · 1104.0583

Quantum System Identification

Daniel Burgarth·Kazuya Yuasa
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Abstract

The aim of quantum system identification is to estimate the ingredients inside a black box, in which some quantum-mechanical unitary process takes place, by just looking at its input-output behavior. Here we establish a basic and general framework for quantum system identification, that allows us to classify how much knowledge about the quantum system is attainable, in principle, from a given experimental setup. Prior knowledge on some elements of the black box helps the system identification. We present an example in which a Bell measurement is more efficient to identify the system. When the topology of the system is known, the framework enables us to establish a general criterion for the estimability of the coupling constants in its Hamiltonian.

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Daniel Burgarth, Kazuya Yuasa. 2011-04-04. Quantum System Identification. https://doi.org/10.1103/physrevlett.108.080502

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