A team has stabilized quantum links over real-world fiber by adapting nanometer-precision stabilization methods from optical clocks, sending a bright reference laser through the same fiber to detect environmental noise and correct it in real time, achieving two-kilometer transmission with high quantum-state fidelity and timing jitter under 100 attoseconds.

The same bright reference laser measures distortions noninvasively, enabling nanometer-level stabilization and ensuring isolation between classical stabilization signals and quantum channels.

This stabilization approach leverages nanometer-precision fiber stabilization from optical clock technology to control the optical path with high accuracy while preserving quantum signals.

The detailed work is published in Optica Quantum, with the authors noting that multiple demonstrations are needed to realize a practical, scalable quantum network.

The report places the advance in the broader quantum networking field, citing foundational works to provide context and credibility.

The researchers emphasize that fast, reliable entanglement between distant nodes is essential for building large-scale quantum networks.

A News & Views piece highlights entanglement between two trapped ions separated by up to 101 kilometers of fiber, underscoring progress toward scalable quantum communication.

A disclosures note reveals RH's involvement with Delft Networks B.V., a company developing quantum-network technology.

The team aims to develop components for a quantum repeater to extend transmission over longer distances and through lossy fibers, moving toward scalable networks with many spatially separated nodes.

Next steps include building a quantum repeater, improving identical single-photon sources, and enhancing detectors to support long-range quantum communication.

Future work envisions extending the infrastructure toward a quantum repeater and scalable networks, with reliable photon sources and efficient detectors to enable entanglement distribution across multiple nodes.

This effort comes from a collaboration between NIST and the University of Colorado, Boulder, leveraging optical frequency metrology and quantum optics to advance distributed entanglement and secure communications.