Coherent Control of Bond Making.

Area of Science:

• Physical Chemistry
• Quantum Control
• Molecular Dynamics

Background:

• Controlling chemical reactions with light is a long-standing goal.
• Femtosecond laser pulses offer precise temporal control over molecular processes.
• Coherent control of bimolecular reactions remains challenging.

Purpose of the Study:

• To demonstrate coherent control of bond making in magnesium dimer molecules.
• To investigate the influence of laser pulse chirp on photoassociation yield.
• To develop and validate a theoretical model for chirp-controlled reactions.

Main Methods:

• Strong-field multiphoton femtosecond photoassociation experiments.
• Ab initio theoretical modeling of molecular dynamics.
• Closed-loop optimization using a learning algorithm for pulse shaping.

Main Results:

• Enhanced magnesium dimer yield with positively chirped pulses.
• Suppressed dimer yield with negatively chirped pulses.
• Validation of chirp-dependent Raman transitions and vibrational coherent dynamics for control.

Conclusions:

• Coherent control of bond making is achievable using shaped femtosecond pulses.
• Pulse chirp plays a crucial role in controlling photoassociation reactions.
• Coherent control of bimolecular photoreactions is feasible under thermal conditions.