Optimal eavesdropping on noisy states in quantum key distribution

Abstract

We study eavesdropping in quantum key distribution with the six state protocol,when the signal states are mixed with white noise. This situation may arise either when Alice deliberately adds noise to the signal states before they leave her lab, or in a realistic scenario where Eve cannot replace the noisy quantum channel by a noiseless one. We find Eve's optimal mutual information with Alice, for individual attacks, as a function of the qubit error rate. Our result is that added quantum noise can make quantum key distribution more robust against eavesdropping.

5 pages, 2 figures

References in corpus (5)

• Quantum Cryptography
• Optimal eavesdropping in quantum cryptography with six states
• An information-theoretic security proof for QKD protocols
• Incoherent and Coherent Eavesdropping in the 6-state Protocol of Quantum Cryptography
• Quantum State Disturbance vs. Information Gain: Uncertainty Relations for Quantum Information

Cited by in corpus (5)

• Fault tolerant architectures for superconducting qubits
• Ping-pong quantum key distribution with trusted noise: non-Markovian advantage
• Quantum key distribution with finite resources: Taking advantage of quantum noise
• Quantumness of pure-state ensembles via coherence of Gram matrix based on generalized $\alpha$-$z$-relative Rényi entropy
• Modified Six State Cryptographic Protocol with Entangled Ancilla States