Broadband optical frequency comb covering spectral regions at UV, VIS, and NIR

Herein, we present a compact, robust, self-referenced optical frequency comb (OFC) ranging from ultraviolet (UV) to near-infrared (NIR) light. The OFC system employs an all-polarization-maintained fiber figure-9 fiber oscillation as a seed laser, which is separated into two branches at the same repetition rate of approximately 100 MHz. One branch is adopted to implement frequency stabilization. Herewith, the repetition rate and the carrier-envelope phase are separately stabilized while the residual phase noises are reduced to 504 μrad and 1.12 rad (ranging from 1 Hz to 3 MHz), corresponding to fractional frequency stabilities of 1.91 × 10⁻¹² and 1.44 × 10⁻¹⁷, respectively. The other branch is used to implement supercontinuum generation and quadruplicate frequency nonlinear processes, thus achieving an OFC system in the ranges of 266, 532, and 600–2200 nm. The precise frequency transferring characteristics of this OFC system exhibit great potential for precision measurement applications and optical frequency synchronization.