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arXiv · 1605.09147

Optimal analysis of ultra broadband energy-time entanglement for high bit-rate dense wavelength division multiplexed quantum networks

Florian Kaiser·Djeylan Aktas·Bruno Fedrici·Tommaso Lunghi·Laurent Labonté·Sébastien Tanzilli
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Abstract

We demonstrate an experimental method for measuring energy-time entanglement over almost 80 nm spectral bandwidth in a single shot with a quantum bit error rate below 0.5%. Our scheme is extremely cost-effective and efficient in terms of resources as it employs only one source of entangled photons and one fixed unbalanced interferometer per phase-coded analysis basis. We show that the maximum analysis spectral bandwidth is obtained when the analysis interferometers are properly unbalanced, a strategy which can be straightforwardly applied to most of today's experiments based on energy-time and time-bin entanglement. Our scheme has therefore a great potential for boosting bit rates and reducing the resource overhead of future entanglement-based quantum key distribution systems.

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Florian Kaiser, Djeylan Aktas, Bruno Fedrici, Tommaso Lunghi, Laurent Labonté, Sébastien Tanzilli. 2016-05-30. Optimal analysis of ultra broadband energy-time entanglement for high bit-rate dense wavelength division multiplexed quantum networks. https://doi.org/10.1063/1.4953785

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