Multielectron effects in charge asymmetric molecules induced by asymmetric laser fields

Area of Science:

• Physical Chemistry
• Atomic and Molecular Physics
• Quantum Dynamics

Background:

• Ultrafast laser pulses can create and probe molecular dynamics.
• Strong-field ionization is a key process in molecular physics.
• Charge asymmetric dissociation involves uneven charge distribution during molecular breakup.

Purpose of the Study:

• Investigate electron dynamics during charge asymmetric dissociation of iodine (I2).
• Study the enhanced ionization mechanism as a function of internuclear separation (R).
• Explore the role of multielectron effects in strong-field molecular ionization.

Main Methods:

• Utilized a 45 fs pump pulse at 800 nm to initiate dissociation.
• Employed a two-color (1ω2ω) probe pulse to monitor dynamics.
• Performed experimental measurements and compared with theoretical simulations.

Main Results:

• Observed spatially asymmetric enhanced ionization in a critical internuclear separation region.
• Identified a counterintuitive ionization channel (I(0+)→I(2+)+I(1+)) involving electron transfer.
• Found that at larger separations, ionization follows a simpler one-electron model.

Conclusions:

• Multielectron effects significantly influence strong-field ionization in molecules.
• The observed enhanced ionization is linked to specific internuclear distances and electron correlation.
• Experimental findings show good qualitative agreement with theoretical simulations.