Co-packaged optics essential as AI datacenters outgrow copper

Matt Crowley (CEO of Scintil Photonics) argues that co-packaged optics (CPO) is now required for AI datacenters and that physics — not manufacturing — forces the shift from copper to optics.

• Main announcement: Matt Crowley explains in Laser Focus World that co-packaged optics (CPO) is the architectural answer for scaling AI clusters toward million-GPU factories, confining copper to ultra-short chip-to-chip paths and moving the rest of the package to fiber to improve power, reach, and density.
• Background and technical details: He cites the physics driving the change: skin effect at ~53 GHz reduces conductive layer to ~0.3 micrometers, dielectric loss plus skin effect can consume >90% of a signal’s power over ~2 meters of high-quality cable, and thus copper reach is fundamentally limited to meters while fiber reaches kilometers.