Three-color ultrabroadband coherent anti-Stokes Raman scattering (CARS) spectroscopy in the range of 400-3500 cm-1 based on a single fiber laser is demonstrated. A 400-fs supercontinuum (SC) with spectral bandwidth between 780 and 1240 nm was generated in a facile manner, by launching 280-fs pulses from the fiber laser into an all-normal-dispersion photonic crystal fiber (PCF) with subsequent compression using a grating pair. It implements a device that can capture the CARS signal of most of the fingerprint range in real time and has a high signal-to-noise ratio. Furthermore, thanks to the excellent temporal overlap of its broad spectrum, the SC was used as both pump and Stokes in three-color broadband CARS (BCARS) spectroscopy of benzonitrile. Nine Raman modes of benzonitrile in the 400-3500 cm-1 range were detected simultaneously.
NSTL
Elsevier
