Light signal survives atmospheric turbulence in campus test

A laser beam left one building at Wits West Campus in Johannesburg and arrived at another looking badly changed. The information inside it was still intact: researchers from the University of the Witwatersrand and the University of Bordeaux had encoded the message in topology, a property of light that can survive deformation, and sent it across hundreds of meters of naturally turbulent air.

The team used optical skyrmions—structured patterns in a laser beam—to carry the data. Atmospheric turbulence, produced by changes in temperature and pressure, significantly altered the beam’s shape between transmitter and receiver. Its topological information nevertheless survived, allowing the message to be recovered without first measuring the distortion or correcting it.

That cuts against the usual architecture of free-space optical communication. Systems that send data through open air commonly need sensors to characterize the atmospheric disturbance, plus specialized hardware and complex calculations to compensate for it. If the new approach scales, the receiver could rely on information that remains stable even when the beam itself does not.

And so what, concretely? The result points toward less technically demanding optical links over difficult atmospheric paths, including possible connections to satellites and spacecraft. In South Africa, lead author Cade Peters also sees a potential route toward better long-range connectivity for remote and underserved communities. Those are future applications, not current deployments.

The evidence is still an experiment conducted between university buildings. The researchers describe it as the first demonstration of this robustness across a real-world optical link under naturally occurring atmospheric conditions. The work, published in Science Advances, also examined applications in conventional and quantum communication, where preserving the integrity of information is especially valuable—but the technology remains at the demonstration stage.