Two-Dimensional Materials for Integrated Photonics: Recent Advances and Future Challenges.

With the development of novel optoelectronic materials and nanofabrication technologies, integrated photonics is a rapidly developing field that will promote the development and application of next-generation photonic devices. In recent years, emerging two-dimensional materials (2DMs) including graphene, transition metal dichalcogenides (TMDCs), black phosphorus (BP), and ternary compounds show many complementarities and unique characteristics over those of traditional optoelectronic materials including broadband absorption, ultrafast carrier mobility, strong nonlinear effects, and compatibility for monolithic integration. Herein, the recent progress on waveguide-integrated active devices for a full photonic circuit based on 2DMs is reviewed. Both the development of nanofabrication techniques and the working mechanism of active photonic components based on 2DMs containing integrated light sources, waveguide-integrated modulators, photodetectors, as well as some advanced 2DMs-based optoelectronic devices are illustrated in detail. In the end, the existing challenges and perspectives on novel 2DMs-integrated photonics are summarized and discussed.