skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effects of physical and chemical surface roughness on the brightness of electron beams from photocathodes

Abstract

The performance of free electron laser x-ray light sources, and systems for ultrafast electron diffraction and ultrafast electron microscopy, is limited by the brightness of the electron sources used. The intrinsic emittance, or equivalently, the mean transverse energy (MTE) of electrons emitted from the photocathode determines the maximum possible brightness in such systems. With ongoing improvements in photocathode design and synthesis, we are now at a point where the physical and chemical surface roughness of the cathode can become a limiting factor. Here we show how measurements of the spatially dependent variations in height and surface potential can be used to compute the electron beam mean transverse energy (MTE), one of the key determining factors in evaluation of brightness.

Authors:
 [1];  [1];  [1];  [2];  [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. Cornell Univ., Ithaca, NY (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1470798
Alternate Identifier(s):
OSTI ID: 1478355
Grant/Contract Number:  
AC02-05CH11231; KC0407-ALSJNT-I0013
Resource Type:
Published Article
Journal Name:
Physical Review Accelerators and Beams
Additional Journal Information:
Journal Volume: 21; Journal Issue: 9; Journal ID: ISSN 2469-9888
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Gevorkyan, G., Karkare, S., Emamian, S., Bazarov, I. V., and Padmore, H. A. Effects of physical and chemical surface roughness on the brightness of electron beams from photocathodes. United States: N. p., 2018. Web. doi:10.1103/PhysRevAccelBeams.21.093401.
Gevorkyan, G., Karkare, S., Emamian, S., Bazarov, I. V., & Padmore, H. A. Effects of physical and chemical surface roughness on the brightness of electron beams from photocathodes. United States. doi:10.1103/PhysRevAccelBeams.21.093401.
Gevorkyan, G., Karkare, S., Emamian, S., Bazarov, I. V., and Padmore, H. A. Fri . "Effects of physical and chemical surface roughness on the brightness of electron beams from photocathodes". United States. doi:10.1103/PhysRevAccelBeams.21.093401.
@article{osti_1470798,
title = {Effects of physical and chemical surface roughness on the brightness of electron beams from photocathodes},
author = {Gevorkyan, G. and Karkare, S. and Emamian, S. and Bazarov, I. V. and Padmore, H. A.},
abstractNote = {The performance of free electron laser x-ray light sources, and systems for ultrafast electron diffraction and ultrafast electron microscopy, is limited by the brightness of the electron sources used. The intrinsic emittance, or equivalently, the mean transverse energy (MTE) of electrons emitted from the photocathode determines the maximum possible brightness in such systems. With ongoing improvements in photocathode design and synthesis, we are now at a point where the physical and chemical surface roughness of the cathode can become a limiting factor. Here we show how measurements of the spatially dependent variations in height and surface potential can be used to compute the electron beam mean transverse energy (MTE), one of the key determining factors in evaluation of brightness.},
doi = {10.1103/PhysRevAccelBeams.21.093401},
journal = {Physical Review Accelerators and Beams},
number = 9,
volume = 21,
place = {United States},
year = {2018},
month = {9}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
DOI: 10.1103/PhysRevAccelBeams.21.093401

Save / Share: