A microcomb, short for microresonator frequency comb, is a novel photonic device that generates a precise series of evenly spaced optical frequencies, akin to the teeth of a comb, across a broad spectrum of wavelengths. It operates based on the phenomenon of Kerr frequency comb generation, which occurs in certain nonlinear optical resonators.
Microcombs are typically fabricated from high-quality optical materials, such as silicon nitride or silicon dioxide, and have dimensions on the order of micrometers. They exploit the nonlinear optical properties of these materials to generate a broad spectrum of closely spaced frequencies through a process called four-wave mixing. This allows them to produce thousands to millions of optical frequencies with extremely high precision and coherence.
These devices have garnered significant interest in various fields of research, including telecommunications, spectroscopy, frequency metrology, and optical frequency synthesis. Their small size, low power consumption, and high coherence make them promising candidates for applications such as optical frequency synthesis for atomic clocks, high-capacity optical communications, and precision spectroscopy for chemical and biological sensing.