Rotational CARS generation through a multiple four-color interaction

A novel technique for the generation of single-pulse rotational CARS spectra is presented and demonstrated flows and flames. The technique is based on a multiple four-color interaction, where the rotational in gas with two photons of different frequencies from a broadband dye laser, and by coupling to a energies are excited photon from a frequency-doubled Nd:YAG laser a rotational CARS photon is created. An interesting third feature of the technique is the possibility of simultaneously generating both a rotational and vibrational using a double-folded BOXCARS arrangement. This technique is demonstrated on N2 CARS spectrum molecules.