Title :
6.5: Electron emission from alkali-coated metal photocathodes
Author :
Montgomery, Eric J. ; Feldman, D.W. ; O´Shea, P.G. ; Pan, P.Z. ; Sennett, N. ; Jensen, K.L.
Author_Institution :
IREAP, Univ. of Maryland, College Park, MD, USA
Abstract :
Quantum efficiency (QE) of a photoemissive surface is lowered via a sub-monolayer coating of adsorbed alkali metal: we here measure QE of cesium, potassium, and sodium on tungsten and refine theoretical predictions using a hard-sphere model to compare to experiment. We identify variation of the percent-monolayer coverage corresponding to peak QE as affected by adsorbate covalent diameter and substrate lattice constant.
Keywords :
caesium; electron emission; photocathodes; sodium; tungsten; adsorbed alkali metal; alkali-coated metal photocathodes; cesium; electron emission; hard-sphere model; percent-monolayer coverage; photoemissive surface; potassium; quantum efficiency; sodium; sub-monolayer coating; tungsten; Cathodes; Coatings; Electron emission; Free electron lasers; Laser theory; Lattices; Photoelectricity; Predictive models; Substrates; Tungsten; Free Electron Laser; cesium; photoemission; potassium; quantum efficiency; sodium; work function;
Conference_Titel :
Vacuum Electronics Conference (IVEC), 2010 IEEE International
Conference_Location :
Monterey, CA
Print_ISBN :
978-1-4244-7098-3
DOI :
10.1109/IVELEC.2010.5503593
