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Updated: May 30, 2026
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Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Electron pair emission from a W(001) surface: photon versus electron excitation
M Muñoz-Navia1, C Winkler, R Patel
1Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany.
Summary
Electron pair emission from tungsten surfaces differs significantly between electron impact and photon absorption. Photon absorption primarily involves double photoemission, not sequential electron impact.
Area of Science:
- Surface science
- Atomic and molecular physics
- Quantum mechanics
Background:
- Electron pair emission is a fundamental process in surface physics.
- Understanding emission mechanisms is crucial for surface characterization and manipulation.
- Previous studies have explored electron-induced emission, but photon-induced mechanisms require further clarification.
Purpose of the Study:
- To investigate and compare electron pair emission from a W(001) surface under electron impact versus photon absorption.
- To elucidate the dominant mechanisms governing photon-stimulated pair emission.
- To differentiate between direct double photoemission and sequential electron impact processes.
Main Methods:
- Utilized a coincidence time-of-flight spectrometer for precise measurement of emitted electrons.
- Employed controlled electron impact to induce pair emission.
- Applied photon absorption to stimulate pair emission from the W(001) surface.
Main Results:
- Observed distinct energy distributions for electron-induced and photon-induced pair emission.
- Photon-stimulated pair emission showed characteristics indicative of a double photoemission process.
- Electron impact as a secondary process following initial photoelectron creation was found to be less significant.
Conclusions:
- Photon-stimulated electron pair emission from W(001) is predominantly driven by a double photoemission mechanism.
- The contribution of sequential electron impact to photon-stimulated pair emission is minimal.
- The findings highlight the differing pathways for electron pair generation under distinct excitation conditions.
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