Chinese Researchers Set New Optical Fiber Speed Record at 3.2 Petabits per Second

Scientists in China have announced a breakthrough in data transmission, achieving a sustained rate of 3.2 petabits per second (Pb/s) over a single optical fiber—a pace that would allow more than 20,000 4K movies to be downloaded in the time it takes to blink.

The test employed a 24‑core fiber, with each core carrying its own data stream through spatial division multiplexing (SDM). By separating the signals spatially, the researchers were able to multiply the capacity of a single strand without resorting to additional physical fibers.

To further boost throughput, the team used a combined S‑band, C‑band, and L‑band (S+C+L) wavelength scheme, spreading the information across three distinct spectral windows. This multi‑band approach reduces interference and maximizes the usable bandwidth of each core.

While the laboratory demonstration does not yet translate directly into commercial deployment, it marks a significant step toward meeting the ever‑growing demand for high‑speed connectivity. Modern data centers, cloud services, and emerging applications such as virtual reality and large‑scale scientific simulations all require ever‑larger data pipes.

Industry analysts note that current submarine cable systems typically operate in the tens of terabits per second range, far below the petabit scale demonstrated in the Chinese experiment. Scaling the technology could potentially shrink the number of fibers needed for future trans‑ocean links, lowering costs and simplifying network architecture.

The researchers have not disclosed all technical details, but they indicated that the record was achieved under controlled laboratory conditions using advanced modulation formats and error‑correction algorithms. Further work will focus on improving reliability, reducing power consumption, and integrating the multi‑core fibers with existing network equipment.

If the approach proves viable for real‑world use, it could reshape the roadmap for next‑generation internet infrastructure, enabling faster data exchange across continents and supporting the data‑intensive services that underpin modern economies.