Practical/ robust quantum key distribution for cheaper high-speed communication that is safe even from future quantum computers

https://www.eurekalert.org/news-releases/1093916

"continuous-variable quantum key distribution compatible with standard components, but requires highly precise hardware/ vast amounts random data... simpler variant uses discrete-modulation: instead of encoding in continuous values range, use 4 distinct quantum states, reducing hardware complexity/ demand for random data, aligns with existing infrastructure, but still can't handle real-world imperfections... upgraded adding composable security: transmitted signals >20 km, 0.011 bits/ symbol secure key rate"

Related:

Quantum dot technique improves multi-photon state generation with immediate applications in secure quantum key distribution protocols
https://phys.org/news/2025-08-quantum-dot-technique-multi-photon.html

Integration of QKD and high-speed classical communications in field-deployed MCFs
https://www.eurekalert.org/news-releases/1095599

Quantum key distribution method tested in urban infrastructure offers secure communications
https://phys.org/news/2025-10-quantum-key-method-urban-infrastructure.html