INFLUENCE OF COHERENT MIXING ON TIME-RESOLVED SFG SPECTRUM OF SURFACE VIBRATION

t are calculated. Using the Lorentzian form of the infrared and visible pulses in frequency domain (expenential in time domain), analytical expression of the time- resolved SFG spectrum is obatined. It is found the coherent mixing effect of the pump and probe pulse manifests itself in the broadening and narrowing of the SFG spectrum with the intrinsic width of / 2 T ( 2 T : dephasing time) at negative and positive d t , respectively, being in qualitaive agreement with recent experimental results (2). Influence of the coherent mixing on the transient behavior of the SFG intensity is also discussed in conjunction to the 2 T determination at longer d t .