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arXiv · 0805.1538

Joint measurement of two unsharp observables of a qubit

Sixia Yu·Naile Liu·Li Li·C. H. Oh
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Abstract

We present a single inequality as the necessary and sufficient condition for two unsharp observables of a two-level system to be jointly measurable in a single apparatus and construct explicitly the joint observables. A complementarity inequality arising from the condition of joint measurement, which generalizes Englert's duality inequality, is derived as the trade-off between the unsharpnesses of two jointly measurable observables.

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Sixia Yu, Naile Liu, Li Li, C. H. Oh. 2008-09-17. Joint measurement of two unsharp observables of a qubit. https://arxiv.org/abs/0805.1538

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