What humans achieve through collaboration also applies to the smallest building blocks of nature: researchers at the University of Rostock demonstrate that photons—the elementary particles of light—can jointly accomplish tasks that are impossible for individual particles.
In their experiment, the team guides light through finely structured waveguides in glass, which function like highly precise roads for photons. Because photons are extremely sensitive and can easily deviate from their intended paths, information is no longer encoded in single photons but in pairs of photons. Only when both photons arrive together at the target is the signal considered valid—an approach that proved to be remarkably robust.
Recently published in Science Advances, the study extends fundamental concepts of quantum mechanics and provides important impulses for future photonic quantum technologies, such as the reliable control of light in quantum computing.
Original publication:https://www.science.org/doi/full/10.1126/sciadv.ady3856
Image: PhD candidate Vera Neef demonstrates the experimental setup.
(Photo: Marco Kirsch)