PsiQuantum's optical circuit switch for AI

PsiQuantum demonstrated an 8×8 optical circuit switch on October 28, 2026, built on its silicon photonics platform originally developed for quantum computing. The device routes light between AI processors without converting signals to electricity, achieving 1.2 dB insertion loss, 40 dB crosstalk, and reconfiguration in under 3 milliseconds, without requiring optical amplification. PsiQuantum is sharing demonstration samples with selected prospective customers and plans to develop commercial products for AI data center connectivity. Google is currently the only major hyperscaler using purely optical switching in an AI data center, using MEMS-based mirrors. On the established-supply side, Marvell's 1.6T Ara optical DSPs are in volume production, and the company is hiring an optics planning executive as AI clusters demand faster links. Credo targets the same market with active electrical cables and optical DSPs including its Cardinal family for large AI fabrics. The broader case is that adding more GPUs only helps if they can communicate fast enough, and that without faster optical links, expensive accelerators sit idle waiting for data.