Fiber Optical Parametric Oscillator and Amplifier for CARS Spectroscopy

We demonstrated coherent anti-Stokes Raman scattering spectroscopy based on fiber optical parametric oscillator and amplifier utilizing four wave mixing in photonic crystal fibers. The output powers and spectra of generated signals were analyzed in detail for various regimes involving spontaneous, stimulated, and amplified parametric processes. The optical parametric oscillator provided tunable signal pulses from 780 to 787 nm with a spectral bandwidth of 3.0 nm, which were then used to seed a fiber optical parametric amplifier, resulting in signal pulses with an average power of 33 mW and spectral bandwidth of 1.1 nm. Using the amplified signal and residual pump pulses, the anti-Stokes signal of polystyrene sample was detected, which confirms the feasibility of the proposed coherent anti-Stokes Raman Scattering light source.