Secret key rate of a continuous-variable quantum-key-distribution scheme when the detection process is inaccessible to eavesdroppers

Abstract

We have developed a method to calculate a secret key rate of a continuous-variable quantum-key-distribution scheme using four coherent states and postselection for a general model of Gaussian attacks. We assume that the transmission line and detection process are described by a pair of Gaussian channels. In our analysis, while the loss and noise on the transmission line are induced by an eavesdropper, Eve, who can replace the transmission line with a lossless and noiseless optical fiber, she is assumed inaccessible to the detection process. By separating the transmission noise and detection noise, we can always extract a larger key compared with the case that all loss and noises are induced by an eavesdropper's interference. An asymptotic key rate against collective Gaussian attacks can be determined numerically for the given channels' parameters. The improvement of the key rates turns out to be more significant for the reverse-reconciliation scheme.

9 pages, 4 figures

References in corpus (11)

• Secure Quantum Key Distribution
• Quantum key distribution over 25 km with an all-fiber continuous-variable system
• Long term performance of the SwissQuantum quantum key distribution network in a field environment
• Field and long-term demonstration of a wide area quantum key distribution network
• Coexistence of continuous variable QKD with intense DWDM classical channels
• Field test of a continuous-variable quantum key distribution prototype
• Upper bounds of eavesdropper's performances in finite-length code with decoy method
• Security of Binary Modulated Continuous Variable Quantum Key Distribution under Collective Attacks
• Security of coherent state quantum cryptography in the presence of Gaussian noise
• Efficient-phase-encoding protocols for continuous-variable quantum key distribution using coherent states and postselection
• Experimental Demonstration of Post-Selection based Continuous Variable Quantum Key Distribution in the Presence of Gaussian Noise

Cited by in corpus (3)

• Trusted detector noise analysis for discrete modulation schemes of continuous-variable quantum key distribution
• Simple security proofs for continuous-variable quantum key distribution with intensity fluctuating sources
• Security against collective attacks for a continuous-variable quantum key distribution protocol using homodyne detection and postselection