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arXiv · 0712.3675

Discrimination of quantum observables using limited resources

Mario Ziman·Teiko Heinosaari
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Abstract

We address the problem of unambiguous discrimination and identification among quantum observables. We set a general framework and investigate in details the case of qubit observables. In particular, we show that perfect discrimination with two shots is possible only for sharp qubit observables (e.g. Stern-Gerlach apparatuses) associated with mutually orthogonal directions. We also show that for sharp qubit observables associated to nonorthogonal directions unambiguous discrimination with an inconclusive result is always possible.

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Mario Ziman, Teiko Heinosaari. 2008-02-18. Discrimination of quantum observables using limited resources. https://doi.org/10.1103/physreva.77.042321

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