THEORY OF TIME-RESOLVED COHERENT RAMAN-SCATTERING WITH SPECTRALLY TAILORED NOISY LIGHT

The theory for the application of spectrally tailored ('two color') no isy light in an interferometric coherent Raman scattering (CRS) experi ment called I-(2)CRS(3c) is presented, The theory is concerned with th e purely resonant contribution to the intensity level I-(2)CRS(3c) sig nal. The tailored beam is modeled as a sum of two Lorentzians where th e center frequency of each Lorentzian is assumed to be under experimen tal control, It is found that not only are the coherent Stokes-Raman s cattering (CSRS) and coherent anti-Stokes-Raman scattering (CARS) sign als emitted, but a third 'hybrid' frequency is also contained in the s ignal. It offers the promise of a new way to up-convert low frequency Raman active modes, while the same dynamic information contained in th e radiation difference oscillations (RDOs) of previous incoherent CRS experiments remains, More generally, it offers an additional degree of freedom that allows for arbitrary experimental control over the posit ion in frequency space in which the hybrid signal will emerge, In addi tion it is shown that the hybrid signal frequency contains dynamically important information in its arbitrarily placed (in frequency space) signal, Plots of monochromatically detected I-(2)CRS(3c) interferogram s calculated for different parameter sets are shown together with the signal spectra, (C) 1997 John Wiley & Sons, Ltd.