Research

Research in the group is focused on using coherent extreme-ultraviolet and soft x-ray light generated by the process of high harmonic generation (HHG) to study electron dynamics in atoms, molecules and materials on femtosecond to attosecond time scales. We use the HHG source in combination with wavelength-tunable laser pulses from an optical parametric amplifier to obtain time-resolved information using multiple probing schemes. One of the main interests is to study ultrafast dynamics near conical intersections in molecules by measuring the third-order non-linear response of excited states. Since third-order response depends sensitively on the electronic character of a given state, our goal is to use such a measurement to quantitatively reconstruct a wave-packet near conical intersections. In addition to non-linear spectroscopy measurements, we also perform Time-Resolved Photoelectron Spectroscopy measurement on molecular targets using a velocity-map imaging spectrometer in order to obtain complementary information about excited state dynamics.