Research

3D control of molecular angular distribution

In the gas, liquid and most condensed phases, molecules are isotropically

distributed with respect to the lab frame of reference, namely they are randomly oriented with no preferred direction. Novel spectroscopic techniques such as High Harmonic Generation, Ultrafast X-ray diffraction/absorption and Molecular Frame Photoelectron/ion Angular Distributions require molecular samples with a preferred direction of orientation. We are developing new methods to enable 3D controlled molecular angular distributions, using both optical and THz fields as two

independent 'molecular handles' over the molecular rotational motion.

Non-linear THz rotational spectroscopy

Nonlinear optical processes have become invaluable tools in

spectroscopy. These require high field strengths, that are commonly

available in the visible and IR. Recent developments of intense THz generation techniques paved the way to nonlinear spectroscopy in the

THz frequency range. We are developing nonlinear THz spectroscopy

for studying multi-level rotational systems.

Time resolved study of molecular dynamics

Upon their electronic excitation, molecules undergo rapid structural changes. cis<-->trans isomerization for example, involves the movement of atoms within a molecule, and the rearrangement of chemical bonds within the molecular frame. We are interested in observing these rearrangements directly and how they change on the femtosecond time scale, in order to shed new light on this fundamental phenomenon in chemistry.