Developing A Toolbox To Probe Reaction Dynamics With Strong Field Ionization And Non-Linear Attosecond Spectroscopy
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چکیده
DEVELOPING A TOOLBOX TO PROBE REACTION DYNAMICS WITH STRONGFIELD IONIZATION AND NON-LINEAR ATTOSECOND SPECTROSCOPYbyTHUSHANI N. HERATHMay 2015Advisor: Dr. Wen LiMajor: Analytical ChemistryDegree: Doctor of Philosopy Electronic motions which happen in 10 to 100 of attoseconds are the heartof many processes in nature. Therefore monitoring and extracting details in thisfundamental level will provide new prospect to the areas as information technology,basic energy science, medicine and life sciences. The challenge being, develop a toolto reach such a fast time scale for real time observation in atomic level. In this thesis wehave addressed this matter using two interesting approaches related to the laser matterinteraction: strong field ionization and nonlinear attosecond spectroscopy. The first partis based on the studies related to the strong field ionization probe. Strong field ionizationprobe was verified to be sensitive not only to the orbital alignment but also to the atomicorientation, which evident the capability of SFI in probing atomic polarization effect inphotodissociation processes. The second part is based on non-linear attosecondspectroscopy. With the use 1 kHz laser and the loose focusing geometry we were ableto produce attosecond pulse trains with a sufficient flux to perform two photon doubleionization. Further, we were also able to extract ion-electron coincidence measurements
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