Field-correlation effects on Raman-enhanced nondegenerate four-wave mixing

The effects of field correlation on Raman-enhanced nondegenerate four-wave mixing (RENFWM) have been investigated by examining the RENFWM spectra as a function of time delay between two beams. We present a theory in which the underlying physics is emphasized. The field correlation has little influence on the RENFWM spectra when the laser has narrow bandwidth. In contrast, the ratio between the resonant and nonresonant RENFWM signal intensities increases as time delay is increased when the laser has broadband linewidth. Experiments with CS₂ as sample have been performed to demonstrate the field-correlation effects on the RENFWM spectra.