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Phase estimation without a priori knowledge in the presence of loss

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 نشر من قبل Rafal Demkowicz-Dobrzanski
 تاريخ النشر 2010
  مجال البحث فيزياء
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We find the optimal scheme for quantum phase estimation in the presence of loss when no a priori knowledge on the estimated phase is available. We prove analytically an explicit lower bound on estimation uncertainty, which shows that, as a function of number of probes, quantum precision enhancement amounts at most to a constant factor improvement over classical strategies



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