Improving parameter estimation of entropic uncertainty relation in continuous-variable quantum key distribution

Abstract

The entropic uncertainty relation (EUR) is of significant importance in the security proof of continuous-variable quantum key distribution under coherent attacks. The parameter estimation in the EUR method contains the estimation of the covariance matrix (CM), as well as the max-entropy. The discussions in previous works have not involved the effect of finite-size on estimating the CM, which will further affect the estimation of leakage information. In this work, we address this issue by adapting the parameter estimation technique to the EUR analysis method under composable security frameworks. We also use the double-data modulation method to improve the parameter estimation step, where all the states can be exploited for both parameter estimation and key generation; thus, the statistical fluctuation of estimating the max-entropy disappears. The result shows that the adapted method can effectively estimate parameters in EUR analysis. Moreover, the double-data modulation method can, to a large extent, save the key consumption, which further improves the performance in practical implementations of the EUR.

10 pages, 4 figures

References in corpus (11)

• Composable security proof for continuous-variable quantum key distribution with coherent states
• Post-selection technique for quantum channels with applications to quantum cryptography
• Continuous Variable Quantum Cryptography using Two-Way Quantum Communication
• Security of continuous-variable quantum key distribution against general attacks
• Composability in quantum cryptography
• Continuous-variable measurement-device-independent quantum key distribution using squeezed states
• Long-distance continuous-variable quantum key distribution with efficient channel estimation
• Finite size analysis of measurement device independent quantum cryptography with continuous variables
• Reverse Reconciliation Continuous Variable Quantum Key Distribution Based on the Uncertainty Principle
• Finite-size analysis of continuous-variable measurement-device-independent quantum key distribution
• Numerical simulation of the optimal two-mode attacks for two-way continuous-variable quantum cryptography in reverse reconciliation