GENERATION OF MIDINFRARED PULSES SUITABLE FOR 2-COLOR IR-SPECTROSCOPYWITH APPROXIMATE-TO-300-FS TIME RESOLUTION, TEMPORAL ANALYSIS VIA 2-PHOTON ABSORPTION IN GERMANIUM AND FIRST APPLICATION

The generation of two independently tunable light pulses in the mid-in frared spectral region is reported here. Synchronously pumping two opt ical parametric oscillators in parallel with a flashlamp-pumped, pulse d Nd:YLF laser delivers tunable radiation in the range 1.2-1.7 mu m wi th duration of 300 fs. Subsequent parametric amplification in AgGaS2 c rystals yields intensive light pulses in the wavelength range of 2.7-7 mu m with duration of approximately 1 ps and energies up to 10 mu J P ulse analysis determining also the zero delay time and the temporal re solution of the experimental system is performed via two-photon absorp tion in germanimm, utilizing the direct band gap. The temporal resolut ion of the two-color ZR-system is determined to be approximately 300 f s and first application to time-resolved spectroscopy in the condensed phase is demonstrated.