Ultrafast Electron-Dipole Interactions in TeO^- Photodetachment.

Area of Science:

• Physical Chemistry
• Ultrafast Spectroscopy
• Molecular Physics

Background:

• Understanding electron-dipole interactions is crucial in atomic and molecular physics.
• Direct experimental observation of transient dipole moments during electron detachment is challenging.
• Previous studies lacked real-time insights into the formation of molecular dipole fields.

Purpose of the Study:

• To provide direct experimental evidence of ultrafast coupling between ejected electrons and dynamically forming dipole moments in TeO.
• To investigate the evolution of transient dipole moments on femtosecond timescales.
• To establish a general method for probing electron-dipole interactions during their formation.

Main Methods:

• Utilized high-resolution cryogenic photoelectron spectroscopy combined with velocity-map imaging.
• Employed femtosecond and picosecond lasers to probe photodetachment of TeO^-.
• Analyzed photoelectron angular distributions (PADs) to resolve electron-dipole interactions.

Main Results:

• Observed previously inaccessible excited states of TeO.
• Resolved rich PADs that encode detailed electron-dipole interactions.
• Demonstrated striking deviations from free-electron behavior, indicating a transient dipole moment evolving on femtosecond timescales (∼60 fs).

Conclusions:

• Provided direct experimental evidence of ultrafast electron-dipole coupling during TeO^- photodetachment.
• Quantified the dipole buildup time, offering real-time access to the birth of a molecular dipole field.
• Established a general approach to study electron-dipole interactions in their nascent stages, advancing ultrafast physics.