Broadband Coherent Anti-Stokes Raman Scattering Spectroscopy Using Pulse-Shaper-Controlled Variable-Wavelength Soliton Pulses from a Photonic Crystal Fiber

Fundamental soliton pulses from a photonic crystal fiber (PCF) were used as variable-wavelength optical pulses in coherent anti-Stokes Raman scattering (CARS) spectroscopy using a single un-amplified laser oscillator in a microscopy setup. Both the center wavelengths and the delay times of soliton pulses were controlled simultaneously by shaping the input pulse of a PCF by the use of a pulse shaper and these parameters were switched automatically in measurement. Broadband CARS signals between 500 and 3100 cm -1 of polymer samples have been measured and the most of the Raman peaks in this frequency range of samples were observed clearly by this method.