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arXiv · 1207.6345

Proof-of-principle demonstration of measurement-device-independent quantum key distribution using polarization qubits

T. Ferreira da Silva·D. Vitoreti·G. B. Xavier·G. C. do Amaral·G. P. Temporão·J. P. von der Weid
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Abstract

We perform a proof-of-principle demonstration of the measurement-device-independent quantum key distribution (MDI-QKD) protocol using weak coherent states and polarization-encoded qubits over two optical fiber links of 8.5 km each. Each link was independently stabilized against polarization drifts using a full-polarization control system employing two wavelength-multiplexed control channels. A linear-optics-based polarization Bell-state analyzer was built into the intermediate station, Charlie, which is connected to both Alice and Bob via the optical fiber links. Using decoy-states, a lower bound for the secret-key generation rate of 1.04x10^-6 bits/pulse is computed.

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T. Ferreira da Silva, D. Vitoreti, G. B. Xavier, G. C. do Amaral, G. P. Temporão, J. P. von der Weid. 2013-11-12. Proof-of-principle demonstration of measurement-device-independent quantum key distribution using polarization qubits. https://doi.org/10.1103/physreva.88.052303

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