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Abstract

The subject of this thesis is to study the effect of phase modulation on the temporal shape of ultrashort laser pulses in the femtosecond domain. Therefore the commercial liquid crystal spatial light modulator "SLM-S320” from JENOPTIC is used. As part of a "Projektpraktikum” thesis a LabVIEW applicationhas been developed to control the SLM which was further improved within this bachelor thesis. The content of this work is divided in three parts. In the first part autocorrelations spectra of short pulses with a bandwidth of 60nm (750nm to 810 nm) were measured. The expected length of approximately25 fs was well confirmed with 31 fs. The shortening effect of the prism compressor on the pulse length could also be shown. Futhermore by using autocorrelation signals the effect of additional glas in the beam path on the pulses with a spectral bandwidth of 320nm (650nm-970 nm) was analysed. In the second part the spectral phase was modulated with the LabVIEW software by applying both linear functions as well as sine-functions. Based on the recorded spectra, the shaped pulses were also simulated. The last part of this thesis is about the impact of pulse shaping on the ability to ionize atoms in the gas phase. A gas a mixture of argon an crypton was used as a target in the sp called reaction microscope (ReMi). It was shown that by modulation generated multiple pulses have a noticeably lower ability to ionize than unshaped pulses. Finally With a further developed LabVIEW sofware the count rate in the reaction microsope was significantly increased by iteratively applying different parabolic phase functions to compensate residual dispersion.