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arXiv · 2208.01789

Picosecond Synchronization of Photon Pairs through a Fiber Link between Fermilab and Argonne National Laboratories

Keshav Kapoor·Si Xie·Joaquin Chung·Raju Valivarthi·Cristián Peña·Lautaro Narváez·Neil Sinclair·Jason P. Allmaras·Andrew D. Beyer·Samantha I. Davis·Gabriel Fabre·George Iskander·Gregory S. Kanter·Rajkumar Kettimuthu·Boris Korzh·Prem Kumar·Nikolai Lauk·Andrew Mueller·Matthew Shaw·Panagiotis Spentzouris·Maria Spiropulu·Jordan M. Thomas·Emma E. Wollman
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Abstract

We demonstrate a three-node quantum network for C-band photon pairs using 2 pairs of 59 km of deployed fiber between Fermi and Argonne National Laboratories. The C-band pairs are directed to nodes using a standard telecommunication switch and synchronized to picosecond-scale timing resolution using a coexisting O- or L-band optical clock distribution system. We measure a reduction of coincidence-to-accidental ratio (CAR) of the C-band pairs from 51 $\pm$ 2 to 5.3 $\pm$ 0.4 due to Raman scattering of the O-band clock pulses. Despite this reduction, the CAR is nevertheless suitable for quantum networks.

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Keshav Kapoor, Si Xie, Joaquin Chung, Raju Valivarthi, Cristián Peña, Lautaro Narváez, Neil Sinclair, Jason P. Allmaras, Andrew D. Beyer, Samantha I. Davis, Gabriel Fabre, George Iskander, Gregory S. Kanter, Rajkumar Kettimuthu, Boris Korzh, Prem Kumar, Nikolai Lauk, Andrew Mueller, Matthew Shaw, Panagiotis Spentzouris, Maria Spiropulu, Jordan M. Thomas, Emma E. Wollman. 2022-08-03. Picosecond Synchronization of Photon Pairs through a Fiber Link between Fermilab and Argonne National Laboratories. https://doi.org/10.1109/jqe.2023.3240756

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