Quantitative agreement between dynamical rocking curves in ultrafast electron diffraction for x-ray lasers

Area of Science:

• Materials Science
• Physics
• Electron Microscopy

Background:

• Electron diffraction offers a method to spatially modulate electron distributions.
• Controlling diffraction intensity is crucial for advanced imaging and X-ray applications.

Purpose of the Study:

• To demonstrate the ability to accurately predict and control electron diffraction spot intensities from patterned silicon membranes.
• To establish a foundation for generating patterned electron beams for novel coherent X-ray methods and ultrafast electron microscopy.

Main Methods:

• Simulated MeV transmission electron diffraction patterns using the multislice method for Si(001) membranes.
• Experimentally validated simulations by comparing intensity maps with results from the ASTA UED facility at SLAC.
• Estimated inelastic and elastic scattering fractions and membrane absorption to determine contrast.

Main Results:

• Accurate prediction and control of electron diffraction spot intensities were experimentally demonstrated and computationally verified.
• Intensity maps of Bragg reflections were successfully compared between simulations and experimental data.
• Contrast in a patterned Si(001) membrane was determined by estimating scattering and absorption.

Conclusions:

• Precise control over electron diffraction patterns is achievable through patterned silicon membranes.
• This control is a critical first step towards generating patterned electron beams.
• The developed methods support advancements in coherent X-ray techniques and femtosecond electron microscopy.