A Chip That Splits Light Into Bands Reads Fast Fiber Without Extra Hardware

Researchers at the University of Southampton and partner labs in Greece, Denmark, France and Belgium have built a photonic chip that splits an arriving light signal into separate frequency bands and reads each band on its own. They report that in laboratory tests the design recovered data sent at 200 gigabaud, or 200 billion on-or-off light pulses a second, over 75 kilometers of ordinary fiber, without the correction equipment such a link normally needs at the receiving end.

Low-cost optical links read light the simple way, by measuring how bright it is. That approach falters as speeds rise: the colors inside a pulse travel at slightly different rates, so the pulse smears and parts of the signal lose power. Writing in Communications Engineering on Oct. 6, 2026, the authors say their receiver counters that fading. They describe it as aimed at low-power, high-speed links in next-generation passive optical networks, the fiber that reaches homes and buildings, and in the short links that connect equipment inside a data center.

The group calls the architecture recurrent optical spectrum slicing. The chip carves the incoming signal into frequency slices, and each slice yields a separate brightness reading; together the readings carry enough to rebuild a signal the fiber has blurred. The team also reports 160 gigabaud over 50 kilometers and 175 gigabaud over 25 kilometers with a denser format carrying four brightness levels rather than a simple on or off. Every run used low-bandwidth components, parts that cannot handle the full signal on their own, plus simple one-pass correction.