Mikhail Petrov

We report recent advances in the development of certification for quantum key distribution (QKD) systems. We give an example of a commercial QKD system that we have analysed for possible loopholes, improved to close the vulnerabilities identified, and designed a set of tests for that can be used by a certification lab [arXiv:2310.20107]. We explain some of the testbenches in this lab, such as an ultrawide spectral characterisation testbench, automated detector testing, and laser damage testbench that verifies the quality of a power limiter. This work is in line with the requirements of the ISO standard for QKD and paves the way for the creation of certification services.

We reverse-engineer, test and analyse hardware and firmware of the commercial quantum-optical random number generator Quantis from ID Quantique. We show that > 99% of its output data originates in physically random processes: random timing of photon absorption in a semiconductor material, and random growth of avalanche owing to impact ionisation. We have also found minor non-random contributions from imperfections in detector electronics and an internal processing algorithm. Our work shows that the design quality of a commercial quantum-optical randomness source can be verified without cooperation of the manufacturer and without access to the engineering documentation.