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Scattering theory of plasmon-assisted entanglement transfer and distillation

J. L. van Velsen·J. Tworzydlo·C. W. J. Beenakker
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Abstract

We analyse the quantum mechanical limits to the plasmon-assisted entanglement transfer observed by E. Altewischer, M.P. van Exter, and J.P. Woerdman [Nature, 418, 304 (2002)]. The maximal violation S of Bell's inequality at the photodetectors behind two linear media (such as the perforated metal films in the experiment) can be described by two ratio's tau_1, tau_2 of polarization-dependent transmission probabilities. A fully entangled incident state is transferred without degradation for tau_1=tau_2, but a relatively large mismatch of tau_1 and tau_2 can be tolerated with a small reduction of S. We predict that fully entangled Bell pairs can be distilled out of partially entangled radiation if tau_1 and tau_2 satisfy a pair of inequalities.

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J. L. van Velsen, J. Tworzydlo, C. W. J. Beenakker. 2003-02-21. Scattering theory of plasmon-assisted entanglement transfer and distillation. https://doi.org/10.1103/physreva.68.043807

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