Peter O’Brien, head of research for photonics packaging and systems integration at Ireland’s Tyndall Research Institute, said academics and commercial companies alike have been working with photonics for years, but the technology faced multiple manufacturing challenges.

Now, O’Brien continues, the technology is ready to make the leap from the lab into widespread application.

“What’s happening now with optics and photonics is there’s kind of a reset,” he says.

It helps that AI chip giant Nvidia has thrown its weight behind the technology.

But shifting to photonics is not a straightforward swap, as it brings together different engineering traditions and different supply chains.

“We’ve really gotten good at bringing the cost down on that electrical side, how to design it, how to manufacture it, how to test it, how to deploy it,” says Andrew Wheeler, senior vice president at Hewlett Packard Labs.

But he says, the industry is still working out how to bring the cost down.

Part of the problem is that different elements of the manufacturing process are distributed across the globe. For example final assembly is done in so-called packaging houses, which are clustered in Taiwan.

Engineering challenges remain. Optical networking devices may generate far less heat but other components within a data centre are still making the local environment hot.

And that’s a problem for optical components which are very sensitive to heat, explains Wheeler. This raises reliability concerns, unless data centre operators and equipment manufacturers can keep within strict thermal limits.

And while optical networks can carry data at – almost – the speed of light, installing and maintaining them will still proceed at human speed. Network designers, field support engineers, installers, all need to learn new skills around installation and servicing.

For example, says Sharp, with fibre, “You can’t take tight turns. There are little nuances on how to structure that.”