Chinese boffins have emerged from their smoke-filled labs having demonstrated optical fibre transmission at 3.2 petabits per second, setting a claimed world record for real-time bidirectional data transfer.
According to Tom’s Hardware the achievement was made using a 10.3-kilometre length of 24-core optical fibre, with information travelling in both directions simultaneously.
The research team includes the National Key Laboratory of Optical Communication Technologies and Networks at China Information Communication Technologies Group, Pengcheng Laboratory and Fiberhome Fujikura Fibre Optic Technology.
The new result improves on the team’s previous record of 2.5 petabits per second, set earlier this year, representing an increase of about 28 per cent. To put the figure into perspective, 3.2 petabits per second equals 3.2 million gigabits per second.
The researchers claim that a single cable operating at this speed could theoretically provide gigabit broadband connections to 3.2 million households simultaneously.
Alternatively, it could transfer more than 20,000 4K films in a single second, assuming someone could find storage hardware capable of keeping up.
The breakthrough relies on spatial division multiplexing, which allows multiple independent data streams to travel through separate cores within the same optical fibre.
Conventional telecommunications fibre generally uses a single core, limiting the number of independent optical paths available for carrying information.
The Chinese system shoves 24 cores into one fibre, greatly increasing simultaneous transmissions without requiring a corresponding increase in cables. The researchers combined this approach with wavelength division multiplexing across three optical transmission bands, S, C, and L.
Using multiple wavelength bands lets more channels operate within each core, further increasing total capacity. However, packing so many signals into a confined space creates technical problems, particularly interference between neighbouring cores.
Known as crosstalk, this interference can degrade signal quality and increase transmission errors. The research team addressed these difficulties through optical system design and signal-processing techniques intended to maintain stable transmission.
The system uses coherent optical modules developed by the researchers, with an architecture designed to meet commercial equipment requirements. That distinction matters because laboratories have already demonstrated faster optical transmission experiments.
Previous research using similar 24-core fibre has achieved speeds of up to 5.29 petabits per second, but those results relied on specialised laboratory equipment and experimental signal processing. The Chinese boffins are claiming a record specifically for real-time bidirectional transmission using a more commercially compatible architecture.
Their system reportedly achieved real-time transmission at 400 gigabits per second per wavelength in the S band and 1.2 terabits per second per wavelength across the C and L bands.
The researchers say the combined system offers approximately 32 times the transmission capacity of conventional commercial single-core G.652 optical fibre arrangements using the C and L bands, which they put at around 100 terabits per second.
Such improvements could become increasingly important as telecommunications operators struggle with rising data traffic.
Large datacentres already require enormous bandwidth to move information between servers, storage systems and computing clusters.
Demand is expected to increase further as operators expand computing infrastructure and deploy increasingly bandwidth-intensive applications.
Multi-core fibre could allow network operators to increase the capacity of existing cable routes without installing proportionately more physical fibre. The technology could apply to national telecommunications backbones, connections between major datacentres, and future 6G infrastructure.
However, the experiment remains a research demonstration, and commercial deployment would require compatible transmission equipment, optical amplifiers and networking infrastructure. The researchers have not announced commercial products or provided a timetable for deploying 3.2-petabit connections.
The development comes 50 years after China began practical optical fibre research in 1976, when scientists experimented with glass fibres about 0.2 millimetres in diameter.
