Miniaturization of frequency-comb sources could open a host of potential applications in spectroscopy, biomedical monitoring, astronomy, microwave signal generation, and distribution of precise time or frequency across networks. This review article places emphasis on an architecture with a semiconductor mode-locked laser at the heart of the system and subsequent supercontinuum generation and carrier-envelope offset detection and stabilization in nonlinear integrated optics.
Keywords: frequency combs; heterogeneous integration; integrated photonics; mode-locked lasers; nonlinear optics; second-harmonic generation; silicon photonics; supercontinuum.