Experimental wavelength-multiplexed entanglement-based quantum cryptography

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