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Finite size analysis of measurement device independent quantum cryptography with continuous variables

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 نشر من قبل Carlo Ottaviani
 تاريخ النشر 2017
  مجال البحث فيزياء
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We study the impact of finite-size effects on the key rate of continuous-variable (CV) measurement-device-independent (MDI) quantum key distribution (QKD). Inspired by the parameter estimation technique developed in [Rupert textit{et al.} Phys. Rev. A textbf{90}, 062310 (2014)]~we adapt it to study CV-MDI-QKD and, assuming realistic experimental conditions, we analyze the impact of finite-size effects on the key rate. We find that, increasing the block-size, the performance of the protocol converges towards the ideal one, and that block-sizes between $10^{6}$ and $10^{9}$ data points can already provide a key rate $sim10^{-2}$ bit/use over metropolitan distances.

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