Report a data issue, formatting problem, or request follow-up. Our team responds within one business day.
Be the first to review this report.
An optical frequency comb is a phase-coherent light source whose spectrum consists of discrete, uniformly spaced lines (“teeth”) that obey (f_n = n f_{\\mathrm{rep}} + f_0), where (f_{\\mathrm{rep}}) is the pulse-repetition rate set by the cavity round-trip and (f_0) is the carrier-envelope offset. In the time domain it corresponds to a train of ultrashort pulses with a fixed carrier-envelope phase; in the frequency domain it acts as a ruler that links optical frequencies to microwave time standards. Combs are generated by passively mode-locked lasers, by electro-optic modulation of continuous-wave lasers, or via Kerr parametric oscillation in high-Q microresonators (“microcombs”), and their bandwidth is often extended by nonlinear spectral broadening. Absolute accuracy and long-term stability are obtained by stabilizing (f_{\\mathrm{rep}}) and (f_0) to external references and, when needed, by self-referencing (e.g., (f)-to-(2f) or (2f)-to-(3f) schemes). Key performance attributes include tooth spacing, usable optical span and flatness, per-tooth power, phase noise, and mutual coherence. Optical frequency combs underpin precision optical metrology and clocks, dual-comb spectroscopy, astronomical spectrograph calibration, coherent communications, and ranging/LiDAR by providing a dense, traceable set of optical frequencies with microwave-readable spacing.
You may also be interested in
