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Updated: Apr 18, 2026
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Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
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Momentum resolution in inverse photoemission
A Zumbülte1, A B Schmidt1, M Donath1
1Physikalisches Institut, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany.
The Review of Scientific Instruments
|February 2, 2015
Summary
We developed a new method to measure electron beam divergence and momentum resolution in inverse-photoemission spectroscopy. This technique analyzes the Shockley surface state
Area of Science:
- Surface science
- Condensed matter physics
- Spectroscopy
Background:
- Accurate determination of electron beam divergence is crucial for momentum resolution in inverse-photoemission spectroscopy (IPES).
- Existing methods often depend on specific experimental conditions or sample properties.
- A direct and reliable method is needed to quantify momentum resolution.
Purpose of the Study:
- To present a novel method for directly determining electron beam divergence and momentum resolution in IPES.
- To establish a technique that is independent of surface quality, energy resolution, and experimental geometry.
- To demonstrate the utility of this method on Cu(111) and its potential for spin-resolved measurements.
Main Methods:
- Measuring a series of IPES spectra on Cu(111).
- Simulating these spectra with varying electron beam divergences.
- Analyzing the influence of beam divergence on the Shockley surface state intensity near the Fermi level.
- Comparing experimental measurements with simulations to quantify momentum resolution.
Main Results:
- The intensity rise of the Shockley surface state upon crossing the Fermi level is directly linked to beam divergence.
- The proposed method allows for the quantification of momentum resolution independent of other experimental parameters.
- For spin-resolved measurements, a single spectrum of a spin-split surface state (e.g., on Au(111)) is sufficient to determine momentum resolution.
Conclusions:
- This study introduces a robust method for determining electron beam divergence and momentum resolution in IPES.
- The technique offers high accuracy and versatility, applicable to both spin-integrated and spin-resolved measurements.
- This advancement facilitates more precise characterization of electronic structures using IPES.
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