1. Passively stable distribution of polarisation entanglement over 192 km of deployed optical fibre
- Author
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Julien Zichi, Sören Wengerowsky, Johannes W. N. Los, Bo Liu, Alberto Mura, Massimo Inguscio, René van der Molen, Val Zwiller, André Xuereb, Thomas Scheidl, Siddarth Koduru Joshi, Rupert Ursin, Davide Calonico, Fabian Steinlechner, Anton Zeilinger, Sergiy M. Dobrovolskiy, Marijn A. M. Versteegh, and Publica
- Subjects
optical fiber ,Photon ,Quantum information ,Computer Networks and Communications ,FOS: Physical sciences ,02 engineering and technology ,Quantum entanglement ,Quantum key distribution ,01 natural sciences ,Bristol Quantum Information Institute ,lcsh:QA75.5-76.95 ,chromatic dispersion ,QETLabs ,Optics ,cables ,Quantum state ,0103 physical sciences ,Computer Science (miscellaneous) ,010306 general physics ,Single photons and quantum effects ,Physics ,Repeater ,Quantum network ,Bell state ,polarization ,Quantum optics ,Quantum Physics ,business.industry ,Photons -- Polarization ,photon ,Statistical and Nonlinear Physics ,021001 nanoscience & nanotechnology ,lcsh:QC1-999 ,Photonics ,Computational Theory and Mathematics ,lcsh:Electronic computers. Computer science ,0210 nano-technology ,business ,Quantum Physics (quant-ph) ,lcsh:Physics ,Optical fibers -- Testing - Abstract
Quantum key distribution (QKD) based on entangled photon pairs holds the potential for repeater-based quantum networks connecting clients over long distance. We demonstrate long-distance entanglement distribution by means of polarisation-entangled photon pairs through two successive deployed 96 km-long telecommunications fibres in the same submarine cable. One photon of each pair was detected directly after the source, while the other travelled the fibre cable in both directions for a total distance of 192 km and attenuation of 48 dB. The observed two-photon Bell state exhibited a fidelity 85% $\pm$ 2% and was stable over several hours. We employed neither active stabilisation of the quantum state nor chromatic dispersion compensation for the fibre., 7 pages, 3 figures
- Published
- 2020