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Metropolitan-scale Entanglement Distribution, with Co-existing Quantum and Classical Signals in a single fiber



Anouar Rahmouni, Paulina Kuo, Ya-Shian Li-Baboud, Ivan Burenkov, Yicheng Shi, Jabir Marakkarakath Vadakkepurayil, Nijil Lal Cheriya Koyyottummal, Dileep Reddy, Mheni Merzouki, Lijun Ma, Abdella Battou, Sergey Polyakov, Oliver T. Slattery, Thomas Gerrits


The development of prototype metropolitan-scale quantum networks is underway and entails transmitting quantum information via single photons through deployed optical fibers spanning several tens of kilometers. Among the major challenges in metropolitan-scale quantum networks are compensation of polarization mode dispersion, high-precision clock synchronization, and compensation for cumulative transmission time fluctuations. One approach addressing these challenges is to co-propagate classical probe signals in the same fiber as the quantum signal. Thus, both signals experience the same conditions and the fiber can therefore be monitored and compensate. Here, we demonstrate the distribution of polarization entanglement with the White Rabbit Precision Time Protocol (WR-PTP) co-propagating in the same single-core fiber strand at metropolitan-scale distances. Our results demonstrate the feasibility of this configuration by achieving high-fidelity entanglement distribution between nodes separated by 100 km of optical fiber. This advancement is a significant step towards the practical implementation of robust and efficient metropolitan-scale quantum networks.


quantum communication, quantum networks, quantum synchronization, co-existance


Rahmouni, A. , Kuo, P. , Li-Baboud, Y. , Burenkov, I. , Shi, Y. , Marakkarakath Vadakkepurayil, J. , Cheriya Koyyottummal, N. , Reddy, D. , Merzouki, M. , Ma, L. , Battou, A. , Polyakov, S. , Slattery, O. and Gerrits, T. (2024), Metropolitan-scale Entanglement Distribution, with Co-existing Quantum and Classical Signals in a single fiber, Optica (Accessed May 19, 2024)


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Created May 7, 2024