Strong-Field Dissociation of state-selected H2+(v,J)

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Compared to ionization of atoms and molecules in strong laser fields, strong field laser dissociation of molecules is understood in much less detail. There are two reasons for this. First of all, compared to ionization strong field dissociation represents a dynamically much more complex process, since not only optical timescales (i.e. the laser pulse duration and optical period) and electronic timescales play important roles, but also vibrational and rotational timescales. Striking phenomena can result from the interplay between all of these timescales, such as the localization of electrons on specific fragments that are formed in the dissociation process. Secondly, strong field dissociation experiments have so far predominantly been carried out in molecular ions, with strong field ionization or the formation of ions in a discharge source typically serving as a preparation step for the subsequent dissociation experiment. A drawback of these approaches is that they tend to form the molecular ion with a broad internal (vibrational, rotational) state distribution, complicating the interpretation of the subsequent experiment and obscuring the observation of many interesting phenomena that should in principle occur. In the present project I will improve on this situation, by performing experiments on strong-field dissociation of state-selected hydrogen molecular ions H2+(v,J), where v and J signify the vibrational and rotational quantum numbers. State-selected molecular ions will be prepared using pulsed field ionization (PFI) techniques that are well-known in the high resolution photoelectron spectroscopy community, but that have so far not been used in the strong field physics community. I will investigate the interplay between electronic, vibrational and rotational degrees of freedom in experiments exploring the role of so-called Laser-Induced Conical Intersections (LICIs), including the role played by the topological phase (Berry phase), as well as the interplay between optical, electronic, vibrational and rotational timescales in electron localization.