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arXiv · 2009.03691

Experimental wavelength-multiplexed entanglement-based quantum cryptography

Johannes Pseiner·Lukas Achatz·Lukas Bulla·Martin Bohmann·Rupert Ursin
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Abstract

In state-of-the-art quantum key distribution (QKD) systems, the main limiting factor in increasing the key generation rate is the timing resolution in detecting photons. Here, we present and experimentally demonstrate a strategy to overcome this limitation, also for high-loss and long-distance implementations. We exploit the intrinsic wavelength correlations of entangled photons using wavelength multiplexing to generate a quantum secure key from polarization entanglement. The presented approach can be integrated into both fiber- and satellite-based quantum-communication schemes, without any changes to most types of entanglement sources. This technique features a huge scaling potential allowing to increase the secure key rate by several orders of magnitude as compared to non-multiplexed schemes.

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Johannes Pseiner, Lukas Achatz, Lukas Bulla, Martin Bohmann, Rupert Ursin. 2020-09-08. Experimental wavelength-multiplexed entanglement-based quantum cryptography. https://doi.org/10.1088/2058-9565%2Fac0519

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