High-Density, Low-Power Optical Communications for AI, Data Center, and More

As digital transistors grow ever denser, the same physical silicon area demands ever more data to work with. For over 50 years, this IO demand has been met by increasingly fast electrical IO, recently achieving speeds >100Gb/s. Packaging technology has not improved at the same rate, resulting in shrinking distances due to high BW-dependent loss (eg <1m at >100Gb/s) and limited numbers of off-package IO channels. Soon, electrical IO will be insufficient to meet the off-package data demands of the most advanced digital chips, such as AI/ML processors and data center switches. Optical IO achieves much greater distances (>10m for multi-mode and >1km for single-mode fiber) and allows high physical IO channel density, enabling these high-performance systems to scale up and out. To be competitive, optical IO solutions must be power efficient, low cost, and reliable. These hurdles are being overcome, and optical IO will be coming to a package near you.