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Quorum of observables for universal quantum estimation

G. Mauro D'Ariano·Lorenzo Maccone·Matteo G. A. Paris
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Abstract

Any method for estimating the ensemble average of arbitrary operator (observables or not, including the density matrix) relates the quantity of interest to a complete set of observables, i.e. a quorum}. This corresponds to an expansion on an irreducible set of operators in the Liouville space. We give two general characterizations of these sets. All the known unbiased reconstruction techniques, i.e. ``quantum tomographies'', can be described in this framework. New operatorial resolutions are given that can be used to implement novel reconstruction schemes.

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G. Mauro D'Ariano, Lorenzo Maccone, Matteo G. A. Paris. 2000-06-01. Quorum of observables for universal quantum estimation. https://doi.org/10.1088/0305-4470%2F34%2F1%2F307

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