Photonic chip–based optical frequency comb using soliton Cherenkov radiation

TLDR

Laser‑induced optical frequency combs on a chip enable precise timing measurements and impact a wide range of technologies. The authors generated combs on an optical chip by inducing and propagating an optical soliton in an engineered microcavity waveguide. The output light formed a coherent comb spanning two‑thirds of an octave, indicating that on‑chip combs can support miniaturized metrology and broad application. Brasch et al., *Science*, this issue p.

Abstract

Timing on a chip Laser-induced optical frequency combs allow precision measurements and affect a broad range of technologies. Brasch et al. generated optical frequency combs on an optical chip (see the Perspective by Akhmediev and Devine). They induced an optical soliton, or optical bullet, and propagated it in an engineered microcavity waveguide. The emitted output light formed a coherent comb of frequencies spanning two-thirds of an octave. Such an on-chip demonstration bodes well for miniaturization of metrological technology and its adaption for widespread application. Science , this issue p. 357 ; see also p. 340