Optical Receivers — from Coherent Transceivers to Short-Reach Scale-Up Solutions

Optical receivers are a critical component in a wide range of industrial applications. Traditionally, they have enabled long-haul transmission through coherent optical technologies. Within data centers, IMDD-PAM4 links are commonly used to interconnect switches across hierarchical layers. More recently, the rapid growth of AI workloads has driven demand for ultra-short-reach optical links, further expanding the role of optical receivers. This talk explores the shared principles and distinct requirements of optical receivers across these three domains — long-haul coherent systems, data center interconnects, and AI-driven short-reach links. A particular focus will be placed on the design of transimpedance amplifiers (TIAs), highlighting how their architecture and performance metrics are tailored to meet the unique challenges of each application.