Scientists Send Secure Quantum Keys Over 62 Miles of Fiber—Without Trusted Devices

Researchers achieved device-independent quantum key distribution over 62 miles of optical fiber, a significant breakthrough that eliminates the need for trusted hardware. The team used entangled rubidium atoms with 90% reliability to transmit encryption keys securely, even if equipment is compromised. While data rates remain extremely low (less than one bit per 10 seconds) and tests were lab-based, this demonstrates the strongest form of quantum-secure communication can now operate at metropolitan-scale distances rather than just tabletop experiments.