| This thesis studies the interactions of intense laser pulses with small polyatomic molecules CH2XY (with X,Y = Cl, Br, I). It is divided into two sections: In the first part, two schemes - photon-locking and hole-burning - are used to control the evolution of a nuclear wave packet on the lowest ionic state of CH2BrI. The experimental results are compared with theoretical predictions and show good qualitative agreement. This is also the first observation of photon-locking in a polyatomic molecule. The second part focuses on controlling strong field ionization. Here a combination of pulse shaping and velocity map imaging of ions and electrons is used to characterize molecular wave packets after ionization with IR ultrafast pulses (central wavelength 780nm). In these experiments basic parameters of the pump pulse like intensity, second/third order phase, or pi-phase flip are systematically scanned. The measurements reveal a superposition of electronic states created by strong field ionization and in certain cases their contributions can be quantified. Last but not least this technique is extended to photo-electron spectra and helps to associate specific features (Freeman-resonances) with ionic states. |
