According to Tom's Hardware, an optical circuit switch (OCS) passes light from fiber to fiber without converting it to an electrical signal, saving power and cutting latency between accelerators. Data center optics can usually tolerate about 3 dB of loss, half the light, and PsiQuantum's switch loses about a quarter of it. In the lab it also measured 40 dB of crosstalk and reconfiguration in under 3 ms.
The company says the result beats the 3 dB target in a request for proposals from Nvidia, which holds a stake through NVentures. Still, Google's mirror-based MEMS switch has 136 ports, and Salience Labs has already shown a 64-port switch. PsiQuantum's figures have not been independently verified.
PsiQuantum says samples have gone to several computing companies, including GPU vendors and hyperscalers, and that a 72x72 version is in development. Commercial products are expected to be announced in the coming months.