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Classical light steering leading to quantum-like security

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 نشر من قبل Tanumoy Pramanik
 تاريخ النشر 2016
  مجال البحث فيزياء
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We show how single system steering can be exhibited by classical light, a feature originating from superposition in classical optics that also enables entanglement and Bell-violation by classical light beams. Single system steering is the temporal analogue of Einstein-Podolsky-Rosen (EPR) steering in the quantum domain, enabling control of the state of a remote system, and can hence be connected to the security of secret key generation between two remote parties. We derive the steering criterion for a single mode coherent state when displaced parity measurements are performed at two different times. The security bound of the Bennett-Brassard 1984 (BB84) protocol under the gaussian cloning attack is calculated to yield an, in principle, ideal and quantum-like key rate using a fine-grained uncertainty relation corresponding to the classical phase space.

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