Toward free-running operation of dual-comb fiber lasers for methane sensing

This is the authors' abstract. We don't add key points for this paper.

The phase information provided by the beat note between frequency combs and two continuous-wave lasers is used to extrapolate the phase evolution of comb modes found in a spectral region obtained via nonlinear broadening. This thereafter enables using interferogram self-correction to fully retrieve the coherence of a dual-comb beat note between two independent fiber lasers. This approach allows the $ f - 2f $f-2f self-referencing of both combs, which is a significant simplification. Broadband near-infrared methane spectroscopy has been conducted to demonstrate the simplified system's preserved performance.