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There is no unmet requirement of optical coherence for continuous-variable quantum teleportation

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 نشر من قبل Howard M. Wiseman
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف H.M. Wiseman




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It has been argued [T. Rudolph and B.C. Sanders, Phys. Rev. Lett. 87, 077903 (2001)] that continuous-variable quantum teleportation at optical frequencies has not been achieved because the source used (a laser) was not `truly coherent. Here I show that `true coherence is always illusory, as the concept of absolute time on a scale beyond direct human experience is meaningless. A laser is as good a clock as any other, even in principle, and this objection to teleportation experiments is baseless.



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