scholarly journals Electron Emission Properties of Silver Oxide and Its Impact on the Secondary Emission Yield of Air-exposed Silver

2022 ◽  
pp. 105231
Author(s):  
Dan Wang ◽  
Yahui Cai ◽  
Yongning He ◽  
Yanan Xu ◽  
Qingqing Jia
2005 ◽  
Vol 473-474 ◽  
pp. 293-296
Author(s):  
György Vida ◽  
Ildikó Beck ◽  
V. Katalin Josepovits ◽  
Miklós Győr

In the present paper the secondary emission and work function of W covered with different thickness Ba layers are compared. The secondary emission and work function were measured by Work Function Spectroscopy (WFS). It is clearly pointed out that the thin Ba coating causes the the enhancement of electron induced secondary electron emission. In high pressure discharge lamps high secondary emission and high thermionic current are required for reliable operating conditions, i.e., for reaching the nominal burning voltage and current etc. The results prove that the Ba spreading on the W surface from an alkali earth tungstate material is advantageous for lowering the work function and, simultaneously, for increasing the secondary emission yield.


Author(s):  
М.В. Гавриков ◽  
Н.Д. Жуков ◽  
Д.С. Мосияш ◽  
А.А. Хазанов

AbstractThe electron emission properties of submicron Si, GaAs, InSb, and InAs semiconductor particles and their multigrain structures have been investigated. The effect of the properties of nanoparticles on the field and secondary emissions has been established. A scanning electron microscopy-based method for measuring the secondary emission coefficient of semiconductors has been proposed. The effect of photoexcitation of the multigrain structure of submicron semiconductor particles on their secondary emission properties has been investigated by the vacuum triode method.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Leandro Olano ◽  
Maria E. Dávila ◽  
John R. Dennison ◽  
Petronilo Martín-Iglesias ◽  
Isabel Montero

Abstract The interaction of ionizing radiation with matter is of critical importance in numerous areas of science and technology like space and vacuum technology and even medicine and biotechnology. Secondary electron emission is a consequence of electron irradiation on materials. We achieve extremely low secondary electron emission yield values smaller than 0.2, even up to incident electron energies ~1 keV, due to an undocumented synergy between neighbouring metal and dielectric domains in composite samples. To investigate this experimental discovery, we propose a simple 3D model where the dielectric and metallic domains are arranged in parallel and interleaved. The proposed surface profile has a triangular shape to model the surface roughness. We obtain a continuous equation to describe the electric field that arises between grounded conductors and charged dielectrics domains. The calculated trajectories of secondary electrons in this 3D geometry are used to predict dynamic secondary emission yield, which strongly depends on the charge accumulated in the dielectric domains. This research paves the way to design new materials of low secondary emission yield, addressing the technological problem not yet resolved to inhibit the electron avalanche in RF equipment that limit their maximum working power.


Author(s):  
R. D. Heidenreich

This program has been organized by the EMSA to commensurate the 50th anniversary of the experimental verification of the wave nature of the electron. Davisson and Germer in the U.S. and Thomson and Reid in Britian accomplished this at about the same time. Their findings were published in Nature in 1927 by mutual agreement since their independent efforts had led to the same conclusion at about the same time. In 1937 Davisson and Thomson shared the Nobel Prize in physics for demonstrating the wave nature of the electron deduced in 1924 by Louis de Broglie.The Davisson experiments (1921-1927) were concerned with the angular distribution of secondary electron emission from nickel surfaces produced by 150 volt primary electrons. The motivation was the effect of secondary emission on the characteristics of vacuum tubes but significant deviations from the results expected for a corpuscular electron led to a diffraction interpretation suggested by Elasser in 1925.


2014 ◽  
Vol 2014 ◽  
pp. 1-23 ◽  
Author(s):  
Alireza Nojeh

Carbon nanotubes have a host of properties that make them excellent candidates for electron emitters. A significant amount of research has been conducted on nanotube-based field-emitters over the past two decades, and they have been investigated for devices ranging from flat-panel displays to vacuum tubes and electron microscopes. Other electron emission mechanisms from carbon nanotubes, such as photoemission, secondary emission, and thermionic emission, have also been studied, although to a lesser degree than field-emission. This paper presents an overview of the topic, with emphasis on these less-explored mechanisms, although field-emission is also discussed. We will see that not only is electron emission from nanotubes promising for electron-source applications, but also its study could reveal unusual phenomena and open the door to new devices that are not directly related to electron beams.


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