Direct-comb molecular spectroscopy with accurate, resolved comb teeth over 43 THz

We demonstrate a dual-comb spectrometer using stabilized frequency combs spanning 177 to 220 THz ( 1360 to 1690nm) in the near infrared. Comb-tooth-resolved measurements of amplitude and phase generate over 4 x 10(5) individually resolved spectral elements at 100MHz point spacing and kilohertz-level resolution and accuracy. The signal-to-noise ratio is 100 to 3000 per comb tooth. Doppler-broadened phase and amplitude spectra of CO2, CH4, C2H2, and H2O in a 30m multipass cell agree with established spectral parameters, achieving high-resolution measurements with optical bandwidth generally associated with blackbody sources.