Extreme Ultraviolet Wave Packet Interferometry of the Autoionizing HeNe Dimer

Area of Science:

• Quantum dynamics
• Atomic and molecular physics
• Ultrafast spectroscopy

Background:

• Interatomic Coulombic decay (ICD) is a key ultrafast process in van der Waals clusters.
• Studying ICD dynamics in simple systems like HeNe provides fundamental insights.
• Vibronic effects play a crucial role in the initial stages of ICD.

Purpose of the Study:

• To investigate resonant interatomic Coulombic decay (ICD) in the HeNe dimer.
• To develop and apply femtosecond extreme ultraviolet wave packet interferometry (XUV-WPI) for studying vibronic dynamics.
• To achieve high temporal and spectral resolution in analyzing ultrafast decoherence processes.

Main Methods:

• Femtosecond extreme ultraviolet wave packet interferometry (XUV-WPI) was employed.
• An XUV phase-cycling scheme was utilized to meet demands for phase stability and sensitivity.
• Quantum interference patterns were detected and analyzed using Fourier analysis.

Main Results:

• Vibronic dephasing and rephasing signatures were observed in the quantum interferences.
• Ultrafast decoherence, attributed to the ICD process, was detected.
• A high-resolution molecular absorption spectrum was obtained via Fourier analysis.

Conclusions:

• Femtosecond XUV-WPI is a powerful technique for real-time analysis of ultrafast ICD.
• The experiment provides detailed insights into vibronic dynamics during ICD.
• The method demonstrates high temporal and spectral resolution for studying quantum processes.