Anahita Khodadad Kashi and Prof. Dr. Michael Kues demonstrated for the first time entanglement-based quantum key distribution using the frequency degree of freedom to enable scalable quantum networks. Credit: Leibniz University Hannover

Light-Based Quantum Networks: A Breakthrough in Secure Data

Scientists at Leibniz University Hannover have developed a cost-effective quantum network security system using frequency-bin coding of light particles, which reduces complexity and equipment costs by 75% while enhancing security against quantum computer threats through a simplified single-detector design that enables dynamic, scalable quantum key distribution.

Long-range quantum key exchange with an untrusted satellite.

Long-range QKD without trusted nodes is not possible with current technology

The ARQ19 patent’s claim of achieving long-range quantum key distribution without trusted nodes is unfounded because it relies on an unexplained confidential classical channel between end users that cannot be quantum-based due to distance limitations, making the system’s security ultimately dependent on this non-quantum channel rather than achieving true quantum security.

Source comparison for three main QKD schemes.

Enhancing quantum cryptography with quantum dot single-photon sources

Quantum dot-based single-photon sources offer superior security for quantum cryptography through their unique combination of on-demand emission, high brightness, low multiphoton contribution, and tunable coherence in photon-number states, outperforming traditional Poisson-distributed sources across multiple cryptographic primitives.