Optical detection of interfering pathways in subfemtosecond multielectron dynamics

Area of Science:

• Quantum dynamics
• Spectroscopy
• Atomic and molecular physics

Background:

• Understanding electron dynamics in many-electron systems is crucial for fundamental physics.
• Autoionizing states play a key role in molecular relaxation processes.
• Resolving ultrafast dynamics requires advanced spectroscopic techniques.

Purpose of the Study:

• To demonstrate the utility of time-resolved coherent anti-Stokes Raman scattering (TR-CARS) for identifying interfering relaxation pathways.
• To investigate the dynamics of autoionizing transients in many-electron systems on femto- and attosecond timescales.
• To differentiate various contributions to the overall relaxation process.

Main Methods:

• Utilizing time-resolved coherent anti-Stokes Raman scattering (TR-CARS) spectroscopy.
• Analyzing the wave-packet dynamics of coherently populated autoionizing states.
• Resolving dynamics on femtosecond and attosecond timescales.

Main Results:

• TR-CARS successfully identifies distinct features arising from different relaxation pathways.
• Wave-packet dynamics of autoionizing transients were resolved with high temporal resolution.
• Bound-bound, continuum-bound, and bound-continuum-bound contributions were identified.
• Distinct spectral features correlate with specific relaxation pathways.

Conclusions:

• TR-CARS is a powerful tool for dissecting complex relaxation dynamics in many-electron systems.
• Ultrafast spectroscopic methods enable the resolution of quantum phenomena on unprecedented timescales.
• Understanding these dynamics is essential for controlling light-matter interactions.