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Updated: May 28, 2026
08:53
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
Band structure effects in above threshold photoemission
F Bisio1, A Winkelmann, C-T Chiang
1CNR-SPIN, Corso Perrone 24, 16152 Genova, Italy. francesco.bisio@spin.cnr.it
Summary
We studied silver surfaces using advanced laser techniques to reveal how electrons behave. Our findings show unique electronic band structures and electron transmission pathways within the crystal.
Area of Science:
- Solid-state physics
- Surface science
- Quantum mechanics
Background:
- Understanding electronic properties of materials is crucial for developing new technologies.
- Photoemission spectroscopy is a powerful tool for probing electron behavior in solids.
- Silver (Ag) is a widely studied material with unique electronic characteristics.
Purpose of the Study:
- To investigate the electronic band structure of the Ag(111) surface.
- To explore multi-photon excitation processes in silver.
- To understand electron transmission through the crystal.
Main Methods:
- Angle-resolved two-photon and three-photon photoemission spectroscopy.
- Utilizing ultrashort laser pulses for excitation.
- Analysis of high-order photoemission spectra.
Main Results:
- Observed multi-photon resonances between electronic states in the Brillouin zone.
- Identified clear signatures of electronic band structure effects in above-threshold photoemission (ATP).
- Distinguished two types of electronic transitions influencing ATP, including those involving intermediate states above the vacuum level.
Conclusions:
- Electronic band structure significantly influences photoemission processes in Ag(111).
- Intermediate states above the vacuum level play a key role in above-threshold photoemission.
- Incoherent electron processes may contribute to multi-photon transitions, offering a way to trace electron transmission.
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