Recent advances in light sources on silicon

Realizing efficient on-chip light sources has long been the “holy-grail” for Si-photonics research. Several important breakthroughs were made in this field in the past few years. In this article, we review the most recent advances in light sources integrated onto mainstream Si platforms and discuss four different integration technologies: Group IV light sources on Si, heterogeneous integration of III–V light sources on Si, blanket heteroepitaxy of III–V light sources on Si, and selective heteroepitaxy of III–V light sources on Si. We start with briefly introducing the basic concepts of each technology and then focus on the recent progress via presenting the most representative device demonstrations. Finally, we discuss the research challenges and opportunities associated with each technology.