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Canonical Phase Measurements in the Presence of Photon Loss

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 نشر من قبل Aravind Chiruvelli
 تاريخ النشر 2009
  مجال البحث فيزياء
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We analyze the optimal state, as given by Berry and Wiseman [Phys. Rev. Lett {bf 85}, 5098, (2000)], under the canonical phase measurement in the presence of photon loss. The model of photon loss is a generic fictitious beam splitter, and we present the full density matrix calculations, which are more direct and do not involve any approximations. We find for a given amount of loss the upper bound for the input photon number that yields a sub-shot noise estimate.



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