Imperial College London
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Nicholas M Harrison

Faculty of Natural Sciences, Department of Chemistry

Chair of Computational Materials Science
 
 
 
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Contact

 

+44 (0)20 7594 5884nicholas.harrison Website

 
 
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Location

 

401LMolecular Sciences Research HubWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@article{Camino:2016:10.1016/j.commatsci.2016.05.025,
author = {Camino, B and Noakes, TCQ and Surman, M and Seddon, EA and Harrison, NM},
doi = {10.1016/j.commatsci.2016.05.025},
journal = {Computational Materials Science},
pages = {331--340},
title = {Photoemission simulation for photocathode design: theory and application to copper and silver surfaces},
url = {http://dx.doi.org/10.1016/j.commatsci.2016.05.025},
volume = {122},
year = {2016}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Obtaining a bright and low emittance electron beam directly from the photocathode is mandatory in order to design high performance free electron lasers (FELs). To achieve this goal a clear understanding of how the emission process is influenced by structure, morphology and composition of the photocathode surface is needed. This is difficult from an experimental point of view because often the atomic scale details of the surface whose emission has been measured are unknown. A predictive theoretical approach capable of determining the effects of surface structure on emission is therefore or great interest. A model to extend the well known three step model (as proposed by Berglund and Spicer) to surface calculations is discussed in this paper. It is based on a layer-by-layer decomposition of the surface electronic structure that can be calculated through reliable and efficient DFT calculations. The advantage of this approach with respect to other existing photoemission calculations is being able to correlate directly the photoemission to the electronic, atomic and chemical structure of the surface. The proposed approach retains, therefore, the simple chemical intuition in the study of surface modifications and their effect on the photoemission. The approach is validated in calculations of the emission from clean copper and silver surfaces. The ability of the model to simulate the change in photoemission in response to adsorbates is tested by simulating monolayers of oxygen, hydrogen and lithium on the copper (1 1 1) surface.
AU  - Camino,B
AU  - Noakes,TCQ
AU  - Surman,M
AU  - Seddon,EA
AU  - Harrison,NM
DO  - 10.1016/j.commatsci.2016.05.025
EP  - 340
PY  - 2016///
SN  - 0927-0256
SP  - 331
TI  - Photoemission simulation for photocathode design: theory and application to copper and silver surfaces
T2  - Computational Materials Science
UR  - http://dx.doi.org/10.1016/j.commatsci.2016.05.025
UR  - http://hdl.handle.net/10044/1/34700
VL  - 122
ER  -
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