Quantum Control of Photoelectron Circular Dichroism

Area of Science:

• Quantum optics
• Molecular physics
• Physical chemistry

Background:

• Chiral molecules exhibit unique interactions with polarized light.
• Photoelectron circular dichroism (PECD) is a sensitive probe of molecular chirality.
• Current methods for enhancing PECD often involve complex experimental setups or limited molecular states.

Purpose of the Study:

• To demonstrate a novel method for coherent control of PECD in randomly oriented chiral molecules.
• To significantly enhance the chiral signature through quantum interference.
• To outperform existing schemes for PECD enhancement.

Main Methods:

• Utilizing a finite manifold of indistinguishable (1+1') resonantly enhanced multiphoton ionization pathways.
• Exploiting quantum interference between multiple photoionization pathways.
• Optimizing photoelectron energy to maximize constructive interference at a common energy level probing different intermediate states.

Main Results:

• Demonstrated coherent control over PECD in randomly oriented chiral molecules.
• Significantly enhanced the chiral signature by interfering multiple ionization pathways.
• Showcased a mechanism that maximizes the number of molecular states contributing to dichroism.
• Outperformed schemes using bichromatic fields or sequential pump-probe ionization.

Conclusions:

• Coherent control via quantum interference offers a powerful strategy for enhancing PECD.
• The demonstrated method provides a robust way to probe molecular chirality.
• This approach opens new avenues for studying chiral matter with high sensitivity.