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

被引：30

作者：

Gevorkyan, G. ^{[1
]}

Karkare, S. ^{[1
]}

Emamian, S. ^{[1
]}

Bazarov, I., V ^{[2
]}

Padmore, H. A. ^{[1
]}

机构：

[1] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA

[2] Cornell Univ, Ithaca, NY 14853 USA

来源：

PHYSICAL REVIEW ACCELERATORS AND BEAMS | 2018年 / 21卷 / 09期

基金：

美国国家科学基金会;

关键词：

MICROSCOPY;

D O I：

10.1103/PhysRevAccelBeams.21.093401

中图分类号：

O57 [原子核物理学、高能物理学];

学科分类号：

070202 ;

摘要：

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.

引用

页数：9

共 23 条

[1] TRANSVERSE ENERGY OF ELECTRONS EMITTED FROM GAAS PHOTOCATHODES [J].