Impact of receiver imbalances on the security of continuous variables quantum key distribution
Instituto de Telecomunicações, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
2 Department of Electronics, Telecommunications and Informatics, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
3 Department of Physics, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
4 I3N and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
Accepted: 7 October 2021
Published online: 18 October 2021
Continuous-variable quantum key distribution (CV-QKD) provides a theoretical unconditionally secure solution to distribute symmetric keys among users in a communication network. However, the practical devices used to implement these systems are intrinsically imperfect, and, as a result, open the door to eavesdropper attacks. In this work, we show the impact of receiver device imperfections on the estimated channel parameters, performance and security of a CV-QKD system. The presented results show that, due to the erroneously estimated channel parameters, non-monitored imbalances can pose a security risk or even reduce the system’s performance. Our results show the importance of monitoring these imbalances and hint at the possibility of compensating for some receiver imbalances by tuning other components.
Key words: Continuous variables / Quantum key distribution / Device imperfections / Excess noise
© The Author(s) 2021
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