ABSTRACT
This chapter provides the light source – more specifically, state-of-the-art hybrid silicon-on-chip laser technologies – and aims to understand the frontier limits of light source technologies. It discusses the potential advantages of interconnects over electrical interconnects, and the advantages of on-chip lasers over off-chip lasers. The bit error rate of an optical link measures the fraction of wrong interpretations of bits on the receiver side and is another important metric to consider. Optical interconnects have been considered as a strong candidate to tackle increasing challenges in chip-level interconnects especially for computers – challenges that include energy consumption, interconnect density, and latency. Key metrics for interconnect technology are bandwidth density, energy efficiency, and latency. The chapter defines key parameters and quantities for laser analysis, including definitions of terminologies and concepts. Based on back-to-back receiver sensitivity and various optical losses, the required laser output power can be estimated.
