An international research team led by the Photonic Network Laboratory at the National Institute of Information and Communications Technology (NICT), and including Sumitomo Electric Industries, Ltd. (Sumitomo Electric) have set a new world record in optical fiber communications, achieving data transmission at 1.02 petabits per second over a distance of 1,808 kilometers (roughly equivalent to the distance from Sapporo to Fukuoka, from Missouri to Montana or from Berlin to Naples). The experiment used a specially designed 19-core optical fiber with a standard 0.125 mm cladding diameter, compatible with existing fiber infrastructure. With a capacity-distance product of 1.86 exabits per second x km—the highest ever recorded—this demonstration marks the fastest long-distance transmission achieved in any optical fiber to date. The result represents a major step forward in developing scalable, high-capacity networks and addressing the world’s growing demand for data.

A standard cladding diameter 19-core optical fiber has been demonstrated to transmit more than 1 petabit per second in the past, but over relatively short distances, well below 1,000 km. The research team has achieved a dramatic extension of the transmission distance by developing a novel 19-core optical fiber also with a standard cladding diameter but with low loss across multiple wavelength bands used in commercial optical fiber transmission systems. In addition, an optical amplification system was developed to support the new optical fiber, which enabled a world record for long-distance high-capacity transmission. The newly developed technology is expected to make a significant contribution to both the expansion of the communication capacity and the long-range extension of optical communication infrastructure in the future, when communication demand increases.

The results of this experiment were accepted as a post-deadline paper presentation at the 48th Optical Fiber Communication Conference (OFC 2025) and presented on Thursday, April 3, 2025.

When a tourist boat left port in the spring of 2024, passengers probably didn’t expect to bear witness to a rare scene where sharks of two species that usually don’t occupy the same habitats flocked to a heavily decayed carcass and fed peacefully for a day. The sharks didn’t exhibit any aggressive behavior towards each other, or the tourist operators and photographers who observed the event. This kind of observation can help scientists better understand inter-species relations and social interactions between some of the oceans’ biggest hunters.