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Title: CsBr Photocathode at 257nm: A Rugged High Current Density Electron Source

Abstract

There is a continuing need for high intensity electron sources that will operate in demountable vacuum and can be externally modulated. Materials with wide bandgap, e.g. diamond, are rugged but need photon energies exceeding the bandgap to emit efficiently and this rules out the use of CW lasers. We have found that a photocathode of CsBr is both adequately intense(>150A/cm{sup 2}) and rugged and can be excited with photons of energy of 4.8eV(257nm). This is below the energy gap of CsBr(7.3eV) but such operation can be explained by the presence of intraband states about 4eV below the conduction band minimum.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
896930
Report Number(s):
SLAC-PUB-12108
TRN: US200705%%75
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Appl.Phys.Lett.
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CURRENT DENSITY; ELECTRON SOURCES; ENERGY GAP; LASERS; PHOTOCATHODES; PHOTONS; Instrumentation,ASTRO, MATSCI, SYNCHRAD, XFEL

Citation Formats

Liu, Zhi, Maldonado, Juan, Sun, Yun, Pianetta, Piero, Pease, R.F.W., and /SLAC, SSRL. CsBr Photocathode at 257nm: A Rugged High Current Density Electron Source. United States: N. p., 2007. Web.
Liu, Zhi, Maldonado, Juan, Sun, Yun, Pianetta, Piero, Pease, R.F.W., & /SLAC, SSRL. CsBr Photocathode at 257nm: A Rugged High Current Density Electron Source. United States.
Liu, Zhi, Maldonado, Juan, Sun, Yun, Pianetta, Piero, Pease, R.F.W., and /SLAC, SSRL. Fri . "CsBr Photocathode at 257nm: A Rugged High Current Density Electron Source". United States. doi:. https://www.osti.gov/servlets/purl/896930.
@article{osti_896930,
title = {CsBr Photocathode at 257nm: A Rugged High Current Density Electron Source},
author = {Liu, Zhi and Maldonado, Juan and Sun, Yun and Pianetta, Piero and Pease, R.F.W. and /SLAC, SSRL},
abstractNote = {There is a continuing need for high intensity electron sources that will operate in demountable vacuum and can be externally modulated. Materials with wide bandgap, e.g. diamond, are rugged but need photon energies exceeding the bandgap to emit efficiently and this rules out the use of CW lasers. We have found that a photocathode of CsBr is both adequately intense(>150A/cm{sup 2}) and rugged and can be excited with photons of energy of 4.8eV(257nm). This is below the energy gap of CsBr(7.3eV) but such operation can be explained by the presence of intraband states about 4eV below the conduction band minimum.},
doi = {},
journal = {Appl.Phys.Lett.},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 05 00:00:00 EST 2007},
month = {Fri Jan 05 00:00:00 EST 2007}
}
  • No abstract prepared.
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