Scientists Push Record 402Tbps Speed Down Standard Fibre Optic Cable

A new world data speed record has just been set after a team of Japanese researchers from the National Institute of Information and Communications Technology (NICT), using a standard commercially available optical fibre, managed to reach a transmission rate of 402.2Tbps (Terabits per second) over a distance of 50km.

The new record, which marks a significant improvement on the previous record of 321Tbps that was set in October 2023, was achieved by constructing the first optical transmission system covering all the transmission bands (O, E, S, C, L and U-bands for a total of 1,505 wavelengths of light) of the low-loss window of standard optical fibres. The previous record was not able to use the O and U bands, which meant it could only harness a total of 1,097 wavelengths.

The new system also combined various new and modern amplification technologies, some developed for this demonstration, including 6 kinds of doped fibre optical amplifiers, and both discrete and distributed Raman amplification. The signal itself was then transmitted over 50km of water absorption peak suppressed optical fibre.

The results clearly show the potential of ultra-wideband transmission, enabled by a new amplifier and wideband spectrum-shaping technology to increase the information carrying capability of new and deployed optical fibres. But at 50km this demonstration, via single-mode fibre, still has a long way to go before it becomes a commercially viable solution to deploy (single-mode fibres are usually used for longer distances).

However, the team said that their future work would “aim to extend the transmission range of such wideband, ultra-high-capacity systems and their compatibility for field deployed fibres“. This could mean that we won’t have to wait long before such cables are pushing the same speeds as this, but over a much greater distance.

Just to be clear, these sorts of systems are more designed for international and national fibre optic capacity links, rather than those local access connections that ultimately serve your own home (although they can help to supply capacity for those from deeper within the network).