Fully tested QKD protocols and working hardware solutions exist and are ready for deployment [ED16]. Indeed, commercial QKD systems have been available for some time, but closer scrutiny has revealed security weaknesses caused not by a failure of the protocol itself, but by vulnerabilities of the physical hardware. Hence, in a quest to ameliorate such side-channel attacks and to improve the overall performance, researchers have continued to propose new and sometimes better QKD protocols. A particularly interesting method, named Measurement Device Independent (MDI) QKD [HKL12], completely avoids side-channel attacks on the detectors, which are most vulnerable part of the system. Another important advantage the MDI QKD protocol is that it locates the most challenging tasks and costly hardware elements at a central node (“Charlie”), which allows for a convenient and cost-effective star-type architecture and removes cost and complexity from the users (“Alices”). At the UofC an MDI QKD system has been demonstrated over deployed optical fibres and in another experiment with coexisting classical communication.

Current projects 

References – MDI-QKD

[AD18]         A Dréau, A Tcheborateva, A El Mahdaoui, et al., arXiv:1801.03304

[AWE17]      AW Elshaari, IE Zadeh, A Fognini, et al., Nature Commun. 8 (1), 379 (2017)

[ED16]         E. Diamanti, H.-K. Lo, B. Qi and Z. Yuan, npj Quantum Info. 2, 16025 (2016)

[GB14]         G Bulgarini, ME Reimer, M Bouwes B., et al. Nano Lett. 14 (7), 4102-4106 (2014)

[HKL12]       HK Lo, M Curty, B Qi, Phys. Rev. Lett. 108, 130503 (2012)

[JJB18]         J J Dubowski, R Stanowski, D Dalacu, et al., Optics & Laser Techn. 103, 382 (2018)

[KDJ15]        KD Jöns, U Rengstl, M Oster, et al., J. of Phys. D: Appl. Phys. 48 (8), 085101 (2015)

[MGP17]      M. Grimau-P., G. H. Aguilar, Q. Zhou, et al., Phys. Rev. Let. 119, 083601 (2017)

[PS17]          P Senellart, G Solomon and A White, Nature Nanotechn. 12, 1026 (2017)

[SH18]         S Haffouz, KD Zeuner, D Dalacu, et al., Nano Lett. 18 (5), pp 3047–3052 (2018)

[SW18]        S Wein, N Lauk, R Ghobadi, C Simon, Phys. Rev. B 97, 205418 (2018)

[XM05]        X Ma, B Qi, Y Zhao, HK Lo., Phys. Rev. A 72, 012326 (2005)