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Joint measurement of two unsharp observables of a qubit

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 نشر من قبل Sixia Yu
 تاريخ النشر 2008
  مجال البحث فيزياء
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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 Englerts duality inequality, is derived as the trade-off between the unsharpnesses of two jointly measurable observables.



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