Reflection-time-of-flight spectrometer for two-electron (e,2e) coincidence spectroscopy on surfaces

Area of Science:

• Surface Science
• Atomic and Molecular Physics
• Spectroscopy

Background:

• Electron-electron correlation spectroscopy (e,2e) provides insights into electronic structures.
• Low-energy electron spectroscopy is crucial for surface analysis.
• Existing spectrometers face limitations in resolution and collection efficiency.

Purpose of the Study:

• To present a novel time-of-flight spectrometer for low-energy (e,2e) correlation spectroscopy.
• To demonstrate the spectrometer's capability for surface analysis.
• To achieve high time and energy resolution for precise measurements.

Main Methods:

• Development of a time-of-flight spectrometer utilizing electron optics and a reflection technique.
• Collection of emitted electrons over a solid angle of approximately 1 steradian.
• Focusing electrons onto a multichannel plate for detection.

Main Results:

• The spectrometer achieves a flight time of approximately 100 ns for 25 eV electrons.
• Demonstrated time resolution of approximately 1 ns and energy resolution of approximately 0.65 eV.
• Acquisition of initial (e,2e) data from a LiF film.

Conclusions:

• The novel spectrometer is effective for low-energy (e,2e) correlation spectroscopy.
• The instrument offers high resolution for surface electronic structure studies.
• The presented data validates the spectrometer's performance and potential.