Experimental demonstration of high quality MeV ultrafast electron diffraction

Area of Science:

• Materials Science
• Physical Chemistry
• Atomic Physics

Background:

• Ultrafast electron diffraction (UED) is crucial for studying dynamic processes.
• Achieving high spatial and temporal resolution simultaneously in UED remains a challenge.

Purpose of the Study:

• To report simulation optimization and experimental demonstration of improved mega-electron-volt ultrafast electron diffraction (MeV UED) performance.
• To showcase MeV UED's capability for atomic-level spatial and sub-picosecond temporal resolution.

Main Methods:

• Utilized ultrashort, high-quality electron pulses from an S-band photocathode radiofrequency gun.
• Employed a polycrystalline aluminum foil as the sample for experimental demonstration.

Main Results:

• Experimentally demonstrated improved spatial resolution in MeV UED.
• Clearly resolved Debye-Scherrer rings for the (111) and (200) planes of aluminum.
• Achieved simultaneous atomic-level spatial resolution and approximately 100 fs temporal resolution.

Conclusions:

• MeV UED is a powerful tool for ultrafast structural dynamics studies.
• The demonstrated performance enhances the capability of MeV UED for probing rapid material changes.