Resource-efficient energy test and parameter estimation in continuous-variable quantum key distribution

Abstract

Symmetry plays a fundamental role in the security analysis of quantum key distribution (QKD). Here we review how symmetry is exploited in continuous-variable (CV) QKD to prove the optimality of Gaussian attacks in the finite-size regime. We then apply these results to improve the efficiency, and thus the key rate, of these protocols. First we show how to improve the efficiency of the energy test, which is one important routine in a CV QKD protocol aimed at establishing an upper bound on the effective dimensions of the otherwise infinite-dimensional Hilbert space of CV systems. Second, we show how the routine of parameter estimation can be made resource efficient in measurement-device independent (MDI) QKD. These results show that all the raw data can be used both for key extraction and for the routines of energy test and parameter estimation.

14 pages, two figures. V2: close to the published version

References in corpus (14)

• Advances in Quantum Cryptography
• Unconditional optimality of Gaussian attacks against continuous-variable QKD
• Optimality of Gaussian Attacks in Continuous Variable Quantum Cryptography
• Long-Distance Continuous-Variable Quantum Key Distribution over 202.81 km of Fiber
• 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
• Continuous-variable QKD over 50km commercial fiber
• Reverse Reconciliation Continuous Variable Quantum Key Distribution Based on the Uncertainty Principle
• Parameter estimation with almost no public communication for continuous-variable quantum key distribution
• Composable security of two-way continuous-variable quantum key distribution without active symmetrization
• Floodlight Quantum Key Distribution: Demonstrating a New Framework for High-Rate Secure Communication
• Security-proof framework for two-way Gaussian quantum-key-distribution protocols
• High-order encoding schemes for floodlight quantum key distribution