Polarization Specific Ultrafast Nuclear Dichroic Responses: Raman Spectral Density Recovery and Coherent Coupling Effects

The frequency selected dichroic ultrafast responses of neat carbon tetrachloride are reported as a function of pump and probe polarization orientations in a standard two beam experimental configuration. The recovery of the Raman spectral density from these experimental observations is demonstrated. The influence of coherent coupling effects, in this one color, electronically nonresonant class of ultrafast pump–probe experiments is considered. While their contribution to Raman spectral densities via birefringent observations can be neglected, these terms can only be eliminated from the dispersed dichroic technique for Raman spectral density recovery when two-color pump–probe studies are performed.