Startups use light instead of wires on chips

Computers that use light instead of electrical current for processing are gaining traction, and startups that have solved the engineering challenge of using photons in chips are getting big investments.

Ayar Labs, a startup developing this technology called silicon photonics, said on Tuesday it had raised $130 million from investors, including chip giant Nvidia.

Although the transistor-based silicon chip has exponentially grown computing power over the past few decades, transistors have reached the width of several atoms and shrinking them even further is a challenge. Not only is it difficult to make something so tiny, but as they get smaller, signals can leak between them.

Thus, Moore’s law, which said that every two years the density of transistors on a chip would double and reduce costs, is slowing, prompting the industry to look for new solutions to deal with the increasingly complex needs of computing intelligence. artificial.

According to data firm PitchBook, last year silicon photonics startups raised more than $750 million, doubling the amount from 2020. In 2016, it was about $18 million.

“Artificial intelligence is growing a lot and taking over a large part of the data center,” Ayar Labs Chief Executive Charles Wuischpard told Reuters. “The challenge of moving data and the energy consumption of that data movement is a big, big question.”

The challenge is that many large ‘machine learning’ algorithms can use hundreds or thousands of chips for processing and there is a bottleneck in the speed of data transmission between chips or servers using current electrical methods.

Light has been used for decades to transmit data over fiber optic cables, including submarine cables, but bringing it down to the chip level was difficult as the devices used to create light or control it are not easy to use. shrink.

In addition to connecting transistor chips, startups using silicon photonics to build quantum computers, supercomputers and chips for autonomous vehicles are also raising big numbers.

PsiQuantum, for example, has raised about $665 million so far, though the promise of quantum computers changing the world is still years away.

And it’s not just startups that drive this technology. Semiconductor manufacturers are also preparing to use silicon chip manufacturing technology for photonics.

GlobalFoundries’ head of wired computing and infrastructure Amir Faintuch said the collaboration with PsiQuantum, Ayar and Lightmatter, which assembles processors using light to accelerate the work of artificial intelligence in the data center, helped build a manufacturing platform. of silicon photonics for others to use, released in March.