Dual-comb spectroscopy using free-running combs with digital phase correction

We realize dual-comb spectroscopy measurements using two types of free-running optical frequency combs, independent Yb:fiber combs with 750-MHz repetition rate and mechanical sharing Er:fiber combs with 51-MHz repetition rate. Assisted by all-computational digital phase correction techniques, the absorption features of gaseous cells are characterized with sufficient signal-to-noise ratio.