Generalized quantum repeater graph states

Physical Review Letters (2025)

 

In this paper, researchers advance a technology called all-photonic quantum repeaters, which are key to sending quantum information over long distances.

A major challenge in these systems is performing entanglement swapping — a process that connects quantum links — because they often lose information.

To address this, the scientists build on earlier methods involving “repeater graph states,” which are special configurations of entangled photons. They generalize these graph states to have more complex connectivity, allowing them to distribute entangled bits more reliably and at a steady rate, even in the presence of photon loss.

Their new scheme is more flexible and efficient than previous approaches. This work contributes to making scalable, loss-tolerant quantum communication networks more practical.

The paper’s authors are Bikun Li, Kenneth Goodenough, Filip Rozpedek and Liang Jiang, who conducted their work at the University of Chicago and the University of Massachusetts Amherst.