Dual-comb correction with spectrally broadened fiber lasers

TL;DR

This paper introduces a simplified method for dual-comb correction using spectrally broadened fiber lasers, eliminating the need for $f - 2f$ self-referencing while maintaining high coherence for spectroscopy applications.

Contribution

The authors develop a novel self-correction technique that leverages phase information from nonlinear broadening, simplifying dual-comb systems without sacrificing performance.

Findings

Successfully retrieved comb coherence without $f - 2f$ referencing

Demonstrated broadband methane spectroscopy

Achieved simplified dual-comb setup with preserved accuracy

Abstract

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 to forego the $f - 2f$ self-referencing of both combs, which is a significant simplification. Broadband near-infrared methane spectroscopy has been conducted as a demonstration of the simplified system's preserved performance.