Enhancing discrete-modulated continuous-variable measurement-device-independent quantum key distribution via quantum catalysis

Abstract

Discrete modulation can make up for the shortage of transmission distance in measurement-device-independent continuous-variable quantum key distribution (MDI-CVQKD), providing a unique advantage against all side-channel attacks but also creating a challenge for further performance improvement. Here we suggest a quantum catalysis (QC) approach for enhancing the performance of the discrete-modulated (DM) MDI-CVQKD in terms of the achievable secret key rate and lengthening the maximal transmission distance. The numerical simulation results show that the QC-based MDI-CVQKD with discrete modulation, involving a zero-photon catalysis (ZPC) operation, can not only obtain a higher secret key rate than the original DM protocol, but also contribute to a reasonable increase of the corresponding optimal variance. As for the extreme asymmetric and symmetric cases, the secret key rate and maximal transmission distance of the ZPC-involved DM MDI-CVQKD system can be further improved under the same parameters. This approach enables the system to tolerate lower reconciliation efficiency, which may provide excellent potential for practical implementations with state-of-art technology.

Non-Gaussian operations in measurement device independent quantum key distribution

“…The efficacy of photon catalysis operation with displacement could further be cherished under realistic conditions such as imperfect state preparation [51] that is abundant in any practical setup. Moreover, in recent years, there have a been several new proposals for tweaking the modulation to further optimize the keyrate-vstransmission distance, such as discrete modulation [52,53], simultaneous classical communication [54], phasemodulation [55] etc.. These render, to the current work immediate relevance and immense interest in present context as well as in other areas of continuous variable quantum information processing [56].…”

Theoretical development of discrete-modulated continuous-variable quantum key distribution

“…Ensemble learning has been used to predict communication failure caused by channel disturbance (Li et al, 2021b). Additionally, some technical means can be applied to further improve the performance (Li and Cvijetic, 2018), such as quantum catalysis (Guo et al, 2020;Ye et al, 2021) and quantum scissors (Ghalaii et al, 2020;, multicarrier (Gyongyosi, 2020).…”