Determining Key Factors for the Open-Loop Control of Molecular Fragmentation Using Shaped Strong Fields

Area of Science:

• Physical Chemistry
• Laser Physics
• Molecular Dynamics

Background:

• Femtosecond laser pulse shaping is crucial for controlling polyatomic molecule fragmentation.
• Understanding the link between laser field properties and observed molecular control remains challenging.

Purpose of the Study:

• To investigate how specific laser pulse parameters influence the ion yield and fragmentation patterns of triethylamine.
• To identify pulse structures that control molecular fragmentation beyond simple intensity dependence.
• To explain observed control mechanisms through interactions with dissociative Rydberg states.

Main Methods:

• Utilized 80 bit binary spectral phase functions to parametrize and map the laser pulse search space.
• Analyzed the impact of pulse parameters on the fragmentation of triethylamine [N(C2H5)3].
• Compared identified pulse structures with pump-probe experimental results.

Main Results:

• Identified specific pulse structures that control the m/z 86 branching ratio in triethylamine fragmentation.
• Demonstrated control beyond simple laser intensity dependence.
• Explained fragmentation control via a dissociative Rydberg state in the neutral molecule.

Conclusions:

• The developed methodology effectively maps laser pulse parameter space for molecular control.
• New insights into laser-induced molecular fragmentation mechanisms were gained.
• This approach can uncover novel control mechanisms in strong field laser-matter interactions.