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arXiv · 2207.08909

Broadband polarization-entangled source for C+L-band flex-grid quantum networks

Muneer Alshowkan·Joseph M. Lukens·Hsuan-Hao Lu·Brian T. Kirby·Brian P. Williams·Warren P. Grice·Nicholas A. Peters
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Abstract

The rising demand for transmission capacity in optical networks has motivated steady interest in expansion beyond the standard C-band (1530-1565 nm) into the adjacent L-band (1565-1625 nm), for an approximate doubling of capacity in a single stroke. However, in the context of quantum networking, the ability to leverage the L-band will require advanced tools for characterization and management of entanglement resources which have so far been lagging. In this work, we demonstrate an ultrabroadband two-photon source integrating both C- and L-band wavelength-selective switches for complete control of spectral routing and allocation across 7.5 THz in a single setup. Polarization state tomography of all 150 pairs of 25 GHz-wide channels reveals an average fidelity of 0.98 and total distillable entanglement greater than 181 kebits/s. This source is explicitly designed for flex-grid optical networks and can facilitate optimal utilization of entanglement resources across the full C+L-band.

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Muneer Alshowkan, Joseph M. Lukens, Hsuan-Hao Lu, Brian T. Kirby, Brian P. Williams, Warren P. Grice, Nicholas A. Peters. 2022-07-18. Broadband polarization-entangled source for C+L-band flex-grid quantum networks. https://doi.org/10.1364/ol.471363

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