Quantum Optics INRIM

Quantum Cryptography

Quantum key distribution (QKD) is a strategic technology that allows two distant parties to share encryption keys with an unprecedented level of security based on the laws of quantum mechanics. Although QKD protocols can be proven unconditionally secure in theory, in practice any deviations of the real system from the idealised model could introduce vulnerabilities. For QKD technology to become a viable real-world solution, end-users need confidence in it, and this requires the characterisation of physical parameters of the practical QKD system devices.

Our group takes advantage of PiQuET - Piemonte Quantum Enabling Technology - infrastructure and instruments to develop characterization methods and protocols for the measurement of the key parameters of commercial QKD devices, testing both active QKD components (as SPADs and SNSPDs) and assembled QKD modules of complete QKD systems (as IdQuantique Clavis3 and Cerberis3 system). We test and develop counter-measures on attacks on QKD systems, as the back-flash attack, analyzing, through a portable optical time domain reflectometer (OTDR) operating at single photon level, the light reflected back from detectors and commercial QKD modules. We also test innovative QKD protocols (as Twin-Field QKD) and Trusted Nodes transmission on real fiber, in collaboration with QN5, on the Italian Quantum Backbone, a 1800 km-long fiber infrastructure now used for high-level time and frequency dissemination services and experiments. In collaboration with QN3 group, we take advantage of single photon radiometry facilities to provide traceable measurements. QKD technology is currently the subject of standardisation efforts at the European and at international level and our group makes its expertise available to all those organisations addressing standardisation issues in QKD and quantum technology in general.


Most relevant pubblications

  • C. Clivati, A. Meda, S. Donadello, S. Virzì, M. Genovese, F. Levi, A. Mura, M. Pittaluga, Z. Yuan, A.J. Shields, M. Lucamarini, I. Degiovanni, D. Calonico "Coherent phase transfer for real-world twin-field quantum key distribution" Nature Communications 13, 157 (2022)

  • H. Georgieva, A. Meda, S. Raupach, H. Hofer, M. Gramegna, I. Degiovanni, M. Genovese, M. Lopez, S. Kueck, “Detection of ultra-weak laser pulses by free-running single-photon detectors: modeling dead time and dark counts effects” Submittet to Quantum Science and Technology

  • M López, A Meda, G Porrovecchio, RA Starkwood, M Genovese, G Brida, M Šmid, CJ Chunnilall, IP Degiovanni, S Kück, “A study to develop a robust method for measuring the detection efficiency of free-running InGaAs/InP single-photon detectors”,EPJ Quantum Technology 7 (1), 14

  • M. Mondin, F. Daneshgaran, F. Di Stasio, S. Arnon, J. Kupferman, M. Genovese, I. Degiovanni, F. Piacentini, P. Traina, A. Meda, M. Gramegna, I. Bari, O. Khan, M. Khan, “Analysis, Design and Implementation of an End-to-End QKD Link”,Advanced Technologies for Security Applications, pp.55-64, Springer, Dordrecht

  • A. Meda, I. P. Degiovanni, A. Tosi, Z. Yuan, G. Brida and M. Genovese, “Quantifying the backflash radiation to prevent zero-error attacks in quantum key distribution” Light: Science & Applications, 2017, 6, e16261, https://doi.org/10.1038/lsa.2016.261

  • M. L. Rastello, I. P. Degiovanni, A. G. Sinclair, S. Kück, C. J. Chunnilall, G. Porrovecchio, M. Smid, F. Manoocheri, E. Ikonen, T. Kubarsepp, D. Stucki, K. S. Hong, S. K. Kim, A. Tosi, G. Brida, A. Meda, F. Piacentini, P. Traina, A. Al Natsheh, J. Y. Cheung, I. Müller, R. Klein and A. Vaigu, “Metrology for industrial quantum communications: the MIQC project” Metrologia, 2014, 51(6), S267-S275,

  • F. Piacentini, A. Meda, P. Traina, H. Kee Suk, I. Degiovanni, G. Brida, M. Gramegna, I. Ruo Berchera, M. Genovese, M. L. Rastello, “Measurement facility for the evaluation of the backscattering in fiber: realization of an OTDR operating at single photon level” International Journal of Quantum Information, 2014, 12 (02), 1461014