Coherent Raman spectroscopy with frequency-shifted and shaped pulses from a photonic-crystal fiber

We demonstrate spectroscopy of coherent anti-Stokes Raman scattering using a frequency-shifted and pulse-shaped output of photonic-crystal fibers pumped by amplified femtosecond Cr: forsterite laser pulses. A dyad of chirped pulses produced by the photonic-crystal fiber with a specially designed dispersion profile are combined with the second-harmonic output of the Cr: forsterite laser, to coherently probe a doublet of Raman resonances in the nonlinear response of a polyvinyl pyrrolidone film, used as a test object.