Nonplanar, crossed-beam phase matching has been employed to obtain pure rotational coherent anti-Stokes Raman spectroscopy (CARS) [and coherent Stokes Raman spectroscopy (CSRS)] spectra to within a few wavenumbers of the incident pump frequency. Using this approach, the rotational CARS (and CSRS) radiation is spatially separated from the pump and Stokes beams; therefore small Raman shifts can be observed with a single monochromator.
© 1980 Optical Society of America
John A. Shirley, Robert J. Hall, and Alan C. Eckbreth, "Folded BOXCARS for rotational Raman studies," Opt. Lett. 5, 380-382 (1980)