Femtosecond molecular science

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This program is based on the three fundamental characteristics of ultrashort laser pulses, 'Time', 'Phase Control', and 'Intensity', and applies them - collectively - to the study of ultrafast molecular dynamics, quantum control, molecular strong field phenomena, and applications. Seven NSERC supported graduate students will carry out this research, receiving unique high level training. There is a world-wide effort to study and control ultrafast atomic motions during chemical reaction. But Chemistry is the coupled rearrangement of both atoms and electrons in excited molecules. Our ultrafast methods uniquely permit simultaneous observation of both electronic and atomic motions. We get the most information by following these dynamics from the "Molecule's Point of View", using molecular frame 3D imaging. Polanyi developed rules relating atomic motions at transition states to outcomes of reactions. We aim to develop analogues of the "Polanyi Rules" for polyatomic reactions. We developed Dynamic Stark Control (DSC), based on the strong electric field rather than the colours of a laser pulse. In DSC, the laser acts as a catalyst without absorption of light. We will extend DSC to control polyatomic reactions and to 3D control of molecular orientation, enabling new classes of dynamics and strong field experiments. As laser fields become stronger still, they exceed the fields which bind electrons. In this regime new physics such as High Harmonic Generation (HHG) emerges, leading to Attosecond Science. To be of lasting impact, Attosecond Science must be extended to polyatomic systems. HHG, a 3 step electronic process involving ionization, propagation and recombination, is pictured as a single electron process. For polyatomic molecules this view is doubtful. We will use a novel strong field method to directly observe driven multi-electron ionization dynamics in polyatomic molecules and compare with theory, with still further details obtained by applying alignment control. We apply ultrafast non-linear optics and phase control to the label-free real-time microscopy of live cells and tissues, commercializing new imaging technology and developing new methods empowering Canadian researchers studying human disease.