Silicon photonics continues to progress but is yet to be adopted for high-performance computing and server architectures, according to market research firm Light Counting.

However, the Super Compute 2022 (SC22) conference hosted two silicon photonics firsts:

1. Professor Keren Bergman of Columbia University reported a working 5Tbit/s transmitter optical chiplet implemented using 80 channels and 3D packaging. The accompanying receiver chip is working and is being lab-tested.
2. Ayar Labs demonstrated its 2Tbit/s TeraPHY chiplet in an end-to-end link, sending and receiving data.

During the panel discussion on high-performance computing and silicon photonics, Intel’s Fabrizio Petrini addressed head-on why optics had such a low profile at the show. “The reality is there is a lot of skepticism about this technology. The adoption is not going to happen anytime soon,” he said.

Systems designers don’t see the implications until they embrace this technology. But factors are aligning for change, and a transition point is being approached in how systems are built, he says; the implications for systems and disaggregation are enormous.

Optical switching is another technology that has been on the fringes of the market for decades. It was all the rage from 1998-2001, but then fizzled out as there weren’t any large scale commercial deployments of photonic switches.

LightCounting reported in August that Google had been using photonic circuit switching in its cloud resident data centers for several years.  The 136×136 port optical circuit switch is Google’s own design.

At SC22, a start-up, Drut Technologies, demonstrated its interface card working with a photonic switch at the top of a SuperMicro server rack. The system allows the server’s CPUs to dynamically configure the resources they need (memory, GPUs) tailored for workloads.