Imaging surface topography using Lloyd's mirror in photoemission electron microscopy.

Area of Science:

• Surface science
• Microscopy techniques
• Nanotechnology

Background:

• Photoemission electron microscopy (PEEM) is a powerful surface imaging technique.
• Quantitative 3D surface analysis in PEEM is challenging.
• Existing methods often lack the resolution or speed for dynamic processes.

Purpose of the Study:

• To develop a novel method for quantitative 3D surface reconstruction using PEEM.
• To enable real-time monitoring of surface topography changes.
• To investigate dynamic phenomena such as reactive wetting.

Main Methods:

• Utilizing Lloyd's mirror setup to modulate electron photoemission.
• Projecting Lloyd's fringes onto 3D surface objects.
• Applying an iterative reconstruction algorithm to correct for optical distortions.
• Analyzing fringe patterns to extract quantitative height information.

Main Results:

• Successfully projected Lloyd's fringes onto 3D surfaces.
• Developed a method to extract 3D height information from 2D plan-view images.
• Achieved sufficient intensity and contrast for real-time surface topography studies.
• Applied the technique to observe unusual contact-line dynamics during reactive wetting of metal droplets.

Conclusions:

• The Lloyd's mirror technique provides a quantitative approach to 3D surface reconstruction in PEEM.
• This method allows for direct extraction of height information from 2D images.
• The technique is suitable for studying dynamic surface processes in real-time.