Chinese team sends 64 Tbps over hollow-core fiber across 626 miles

The record run

A research team in China has demonstrated two-way data transmission at 64 terabits per second in each direction over a hollow-core fiber link spanning 1,007 kilometers, or about 626 miles, according to TechRadar. The work was carried out by the China Telecom Research Institute, fiber maker Yangtze Optical Fibre and Cable (YOFC) and equipment vendor ZTE Corporation.

TechRadar, citing CCTV and Interesting Engineering, reports that the capacity is equivalent to downloading 160 films in 4K resolution at 50GB each every second. Individual signals crossed the full length of the link in 3.43 milliseconds. The team also reported a 30% reduction in latency compared with earlier hollow-core trials of the same type, along with improved signal-to-noise ratios and loss margins.

Why air beats glass

Conventional fiber carries light through a solid glass core. Hollow-core fiber instead guides the signal through air, with a glass lattice surrounding the hollow center. The glass structure keeps the light traveling in the right direction, but because most of the path is air rather than glass, the signal meets less resistance. That translates into faster transmission and lower latency.

TechRadar notes that recent progress has focused on the design and composition of that glass lattice, which is central to reducing lag and improving stability. The 1,007-kilometer span is roughly 50 times longer than previous hollow-core trials of the same kind, suggesting the technology is moving from laboratory demonstrations toward distances that matter for real networks.

Cloud providers are already buying in

Hollow-core fiber is not purely experimental. TechRadar reports that Microsoft signed a deal last year with Corning and Heraeus to scale up production of the fiber for its Azure cloud platform, and that around 15,000 kilometers (about 9,321 miles) of hollow-core fiber should be in place supporting Azure by the end of this year.

That deployment points to where the technology fits first: data centers and long-haul infrastructure rather than the connection into a home. TechRadar notes that hollow-core fiber is better suited to large infrastructure projects than to the cabling that links broadband networks to individual premises, though it has also been tipped as a possible support for cellular networks in the future.

What still stands in the way

Hollow-core fiber remains harder to manufacture and install than the solid-core fiber that dominates networks today, according to TechRadar. Those practical difficulties are the main reason the technology has taken years to move beyond early trials.

The Chinese demonstration does not remove those hurdles, but it shows that some of them are being chipped away. Longer spans, lower latency and better signal quality all make the case for commercial deployment stronger. For readers, the near-term effect is likely to be felt indirectly, through faster and more responsive cloud and data-center services rather than a new cable arriving at the door.