| This dissertation presents a laser based measurement technique called Coherent anti-Stokes Raman spectroscopy(CARS), which technique should meet the frequency requirements and phase matching. Raman media and the surrounding environmental information could be gained from CARS spectra. After combining with femtosecond technique, femtosecond time-resolved CARS spectra have a highly spatial and temporal resolution, which can be used in detecting molecular ultra-fast dynamics within femtosecond time and temperature measurement under adverse conditions.Coherent anti-Stokes Raman Scattering is a kind of nonlinear four-wave mixing effects. This dissertation overviews the CARS theory from nonlinear optical process, and analyzes the condition that femtosecond CARS spectral intensity changes with the time.This dissertation also presents the study of experimental measurement in femtosecond time-resolved CARS spectra. These experiments use femtosecond laser system as the laser source. The experimental system can detect femtosecond time-resolved CARS signal from samples in form of liquid and vapor under the condition of room temperature and low vapor pressure. It has also studied the output characteristics of CARS signal.Based on the theoretical and experimental studies, this dissertation then has done some researches on detecting molecular ultra-fast dynamics and temperature measurement. In study of ultra-fast dynamics in molecular detection, depending on the delay-time between the probe pulse and the pump/Stokes pulse pairs, the wave-packet motion on both the electronically excited and ground state can be detected as oscillations in the CARS transient signal, and the information of the vibrational level of both states could be obtained through the oscillations. Then in temperature measurement part, the dissertation has studied both in theory and experiments. The experimental data and theoretical fitting results have a strong corresponding, and the experiments present a high repeatability.
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