Molecular Dual-Comb Spectroscopy in the Near and Mid-Infrared

Abstract

Dual-comb spectroscopy (DCS) has been demonstrated to be a powerful tool in allowing for absorption spectroscopy to be conducted using the interferometric beating between two phase-coherent frequency combs. The technique allows for time-resolved measurements to be conducted with high spectral resolution while preserving a broad spectral bandwidth. Additionally, due to the availability of nonlinear wavelength conversion methods, frequency combs operating in the near-infrared (NIR) telecom band can be spectrally converted to cover any desired region from the visible up to the long-wave infrared (LWIR). We present broadband DCS used to probe systems such as NIR molecular signatures during their forma- tion in a laser-produced plasmas via second harmonic generation (SGH), or from difference frequency generation (DFG) to access DCS in the LWIR.