Scientists just sent unhackable quantum keys across 120 kilometers
Science News from research organizations Scientists just sent unhackable quantum keys across 120 kilometers Date: May 9, 2026 Source: Light Publishing Center, Changchun Institute of Optics, CAS Summary: Scientists have taken a major step toward ultra-secure quantum communication by demonstrating a remarkably stable quantum encryption system that worked across more than 120 kilometers of optical fiber. Using tiny semiconductor quantum dots that emit single particles of light on demand, the team achieved one of the highest secure key rates yet for this type of technology while maintaining continuous operation for over six hours without manual adjustments. Share: Facebook Twitter Pinterest LinkedIN Email FULL STORY Scientists just pushed quantum-secure communication closer to reality with a remarkably stable system that kept encrypted quantum signals running for hours across 120+ kilometers of fiber. Credit: Shutterstock Quantum key distribution (QKD) is widely considered the most advanced form of quantum cryptography, offering a path toward virtually unbreakable security for the future quantum internet. One promising technology behind these secure systems involves semiconductor quantum dots (SQDs), tiny solid-state light sources capable of generating high-quality single photons for quantum communication. These devices could help boost secure key generation rates while also supporting future quantum repeaters needed for large-scale quantum networks. Another important development is time-bin encoding, a technique that stores information in the arrival times of photons. This method is especially attractive for long-distance quantum communication because it is naturally resistant to many of the environmental disturbances that can disrupt fiber optic networks. Stable Quantum Encryption Over 120 Kilometers An international research team from universities in Germany and China has now demonstrated the first true time-bin QKD system powered by an on-demand telecom semiconducto
