To make the cluster state, specially designed crystals convert ordinary laser light into a type of quantum light called squeezed light, which is then weaved into a cluster state by a network of mirrors, beam-splitters and optical fibres.
The team's design allows for a relatively small experiment to generate an immense two-dimensional cluster state with scalability built in. Although the levels of squeezing—a measure of quality—are currently too low for solving practical problems, the design is compatible with approaches to achieve state-of-the-art squeezing levels.
The team says their achievement opens up new possibilities for quantum computing with light.
"In this work, for the first time in any system, we have made a large-scale cluster state whose structure enables universal quantum computation." Says Dr. Hidehiro Yonezawa, Chief Investigator, CQC2T at UNSW Canberra. "Our experiment demonstrates that this design is feasible—and scalable."
CQC2T - www.cqc2t.org