Absorption spectroscopy using interference between optical frequency comb and single-wavelength laser

Optical frequency combs have the potential to be applied not only to frequency metrology but also to various spectroscopic measurements replacing incoherent wide-frequency band light sources and single-wavelength laser sources. In this study, we propose a system of absorption spectroscopy for single electronic transitions using the frequency-comb laser source. This spectroscopic method utilizes the interference between the probing frequency comb and an additional single-wavelength laser beam and detects power spectra of beat signals in the interfered laser beam. This method enables us to measure single-transition absorption spectra neither using a large-scale spectrometer nor scanning the laser-beam frequency.