Quantum CDMA-Based Continuous Variable Quantum Key Distribution Using Chaotic Phase Shifters

We present a quantum code-division multiple-access q-CDMA framework for multiuser continuous-variable quantum key distribution CV-QKD over a shared quantum channel. The proposed architecture employs chaotic phase shifters to encode and decode quantum states, enabling efficient multiplexing and...

Semi-Device-Independent Quantum Random Number Generator Resistant to General Attacks

Quantum random number generators QRNGs produce true random numbers based on the inherent randomness of quantum theory, rendering them a foundational segment of quantum cryptography. Distinguished from trusted-device QRNGs whose security depends on characterized devices, semi-device-independent...

Finite-Size Security of QKD: Comparison of Three Proof Techniques

We compare three proof techniques for composable finite-size security of quantum key distribution under collective attacks, with emphasis on how the resulting secret-key rates behave at practically relevant block lengths. As a benchmark, we consider the BB84 protocol and evaluate finite-size...

An Introductory Review of the Theory of Continuous-Variable Quantum Key Distribution: Fundamentals, Protocols, and Security

Continuous-variable quantum key distribution CV-QKD has emerged as a promising approach for secure quantum communication, offering advantages such as high key generation rates, compatibility with standard telecommunication infrastructure, and potential for integration on photonic chips. This revi...

Analytic Rényi Entropy Bounds for Device-Independent Cryptography

Device-independent DI cryptography represents the highest level of security, enabling cryptographic primitives to be executed safely on uncharacterized devices. Moreover, with successful proof-of-concept demonstrations in randomness expansion, randomness amplification, and quantum key distributio...