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A model of glow gas discharge in the presence of a thin insulating film on the cathode is formulated. It takes into account that under discharge current flow, due to the bombardment of the cathode by ions, positive charges accumulate on the film and generate strong electric field in it. As a result, field emission of electrons from the cathode metal substrate into the film starts, which, with an increase in its temperature, transforms into thermal-field emission. Electrons move in the film, being accelerated by the electric field and decelerated in collisions with phonons, and some of them leave the film into the discharge, increasing the effective ion-electron emission yield of the cathode. The electric field strength in the film is determined from the condition that the density of the discharge current and the density of the emission current from the cathode metal substrate into the film are equal. The dependences of the film emission efficiency, the effective ion-electron emission yield of the cathode, and the discharge characteristics on the cathode temperature are calculated. It is shown that already at a temperature exceeding room temperature by several hundred degrees, the temperature enhancement of field electron emission from the metal substrate into the film can noticeably influence the cathode emission properties and the discharge voltage-current characteristic.

The theories of thermionic emission and field emission (also known as the Richardson–Dushman [RD] and Fowler–Nordheim [FN] Laws, respectively) were formulated more than 80 years ago for bulk materials. In single-layer graphene, electrons mimic massless Dirac fermions and follow relativistic carrier dynamics. Thus, their behavior deviates significantly from the nonrelativistic electrons that reside in traditional bulk materials with a parabolic energy-momentum dispersion relation. In this article, we assert that due to linear energy dispersion, the traditional thermionic emission and field emission models are no longer valid for graphene and two-dimensional Dirac-like materials. We have proposed models that show better agreement with experimental data and also show a smooth transition to the traditional RD and FN Laws.

A model is proposed for describing a cathode layer of a glow gas discharge in the presence on a cathode of a dielectric oxide film, the thickness of which has different values on different sections of its surface. The influence is studied of the non-uniformity of the film thickness on the effective coefficient of the ion-electron emission as well as on the discharge characteristics.

Introducing up-to-date coverage of research in electron field emission from nanostructures, Vacuum Nanoelectronic Devices outlines the physics of quantum nanostructures, basic principles of electron field emission, and vacuum nanoelectronic devices operation, and offers as insight state-of-the-art and future researches and developments.  This book also evaluates the results of research and development of novel quantum electron sources that will determine the future development of vacuum nanoelectronics. Further to this, the influence of quantum mechanical effects on high frequency vacuum nanoelectronic devices is also assessed. Key features: • In-depth description and analysis of the fundamentals of Quantum Electron effects in novel electron sources. • Comprehensive and up-to-date summary of the physics and technologies for THz sources for students of physical and engineering specialties and electronics engineers. • Unique coverage of quantum physical results for electron-field emission and novel electron sources with quantum effects, relevant for many applications such as electron microscopy, electron lithography, imaging and communication systems and signal processing. • New approaches for realization of electron sources with required and optimal parameters in electronic devices such as vacuum micro and nanoelectronics. This is an essential reference for researchers working in terahertz technology wanting to expand their knowledge of electron beam generation in vacuum and electron source quantum concepts. It is also valuable to advanced students in electronics engineering and physics who want to deepen their understanding of this topic. Ultimately, the progress of the quantum nanostructure theory and technology will promote the progress and development of electron sources as main part of vacuum macro-, micro- and nanoelectronics.

We propose a model for a low-current gas discharge in a mixture of argon and mercury vapor in the presence of a thin dielectric film on the surface of a cathode. The model takes into account that in such a mixture, a significant contribution to ionization of the working gas can be made by the ionization of mercury atoms during their collisions with metastable excited argon atoms. Positive charges accumulate in the discharge on the surface of the film, creating an electric field in the dielectric sufficient to induce field electron emission from the metal substrate of the electrode into the dielectric. These electrons are accelerated in the film by an electric field and can exit it into the discharge volume. This increases the effective ion–electron emission yield of the cathode. The temperature dependences of the discharge characteristics show that due to a rapid decrease in the concentration of mercury vapor in the mixture with decreasing temperature, the electric-field strength in the discharge gap and the discharge voltage increase. The presence of a thin dielectric film on the cathode can improve its emission properties and significantly decrease the discharge voltage. These phenomena result in a decrease in the energy of ions and atoms bombarding the cathode surface and, consequently, a reduction in the intensity of cathode sputtering in the discharge.

Electron emission represents the key mechanism enabling the development of devices that have revolutionized modern science and technology. Today, science still relies on advanced electron-emission devices for imaging, electronics, sensing, and high-energy physics. New generations of emission devices are continuously being improved based on innovative materials and the introduction of novel physical concepts. Recent advances are highlighted by emerging low-work-function and low-dimensional materials with unusual electronic and thermal properties. Nanotubes, nanowires, graphene, and electron-emission models are discussed in this issue, as well as original mechanisms, such as the thermoelectronic effect, thermionic emission, and heat trap processes. Advances in electron-emission materials and physics are driving a renaissance in the field, both opening up new applications, such as energy conversion and ultrafast electronics, as well as improving traditional applications in electron imaging and high-energy science.

The secondary electron emission coefficient of dielectric materials will have an important impact on the performance of electronic devices and equipment. In order to understand the secondary electron emission coefficient of common dielectric materials, the collection electrode negative bias method is introduced in this study. First, the measurement method of secondary electron emission coefficient of dielectric materials is analyzed, and 20 common dielectric materials are introduced, the secondary electron emission coefficients of 20 kinds of common dielectric materials were measured and analyzed, which laid the foundation for the subsequent application of dielectric materials. The results show that among common dielectric materials, the secondary electron emission coefficients of alumina, silica and muscovite are relatively high, while those of polyimide, polycarbonate and polyester are relatively low; The surface roughness of the material will also have an important impact on the secondary electron emission coefficient. With the gradual increase of the surface roughness of the material, the undulation of the material surface will have a shielding effect and absorption effect on the secondary electrons, which will eventually lead to the gradual reduction of the secondary electron emission coefficient of the material. The research results can provide data support for the establishment of the database of secondary electron emission characteristics of common dielectric materials.

The effect of isothermal conditions on the trapping/detrapping process of charges in e-beam irradiated thermally aged XLPE insulation in scanning electron microscopy (SEM) has been investigated. Different isothermal conditions ranging from room temperature to 120 °C are applied on both unaged and aged XLPE samples (2 mm thick) by a suitable arrangement associated with SEM. For each applied test temperature, leakage, and influence currents have been measured simultaneously during and after e-beam irradiation. Experimental results show a big difference between the fresh and aged material regarding trapping and detrapping behavior. It has been pointed out that in the unaged material deep traps govern the process, whereas the shallow traps take part in the aged one. Almost all obtained results reveal that the trapped charge decreases and then increases as the temperature increases for the unaged sample. A deflection temperature corresponding to a minimum is observed at 50 °C. However, for the aged material, the maximum trapped charge decreases continuously with increasing temperature, and the material seems to trap fewer charges under e-beam irradiation at high temperature. Furthermore, thermal aging leads to the occurrence of detrapping process at high temperatures even under e-beam irradiation, which explains the decrease with time evolution of trapped charge during this period. The recorded leakage current increases with increasing temperature for both cases with pronounced values for aged material. The effect of temperature and thermal aging on electrostatic influence factor (K) and total secondary electron emission yield (σ) were also studied.

This work presents a detailed analysis of the performance of X‐ray magnetic circular dichroism photoemission electron microscopy (XMCD‐PEEM) as a tool for vector reconstruction of magnetization. For this, 360° domain wall ring structures which form in a synthetic antiferromagnet are chosen as the model to conduct the quantitative analysis. An assessment is made of how the quality of the results is affected depending on the number of projections that are involved in the reconstruction process, as well as their angular distribution. For this a self‐consistent error metric is developed which allows an estimation of the optimum azimuthal rotation angular range and number of projections. This work thus proposes XMCD‐PEEM as a powerful tool for vector imaging of complex 3D magnetic structures. The performance of X‐ray magnetic circular dichroism photoemission electron microscopy for vector imaging of complex three‐dimensional magnetic textures is investigated.

Plasmonic metal electrodes with subwavelength nanostructures are promising for enhancing light harvesting in photovoltaics. However, the nonradiative damping of surface plasmon polaritons (SPPs) during coupling with sunlight results in the conversion of the excited hot‐electrons to heat, which limits the absorption of light and generation of photocurrent. Herein, an energy recycling strategy driven by hot‐electron emission for recycling the SPP energy trapped in the plasmonic electrodes is proposed. A transparent silver‐based plasmonic metal electrode (A‐PME) with a periodic hexagonal nanopore array is constructed, which is combined with a luminescent organic emitter for radiative recombination of the injected hot‐electrons. Owing to the suppressed SPP energy loss via broadband hot‐electron emission, the A‐PME achieves an optimized optical transmission with an average transmittance of over 80% from 380 to 1200 nm. Moreover, the indium‐tin‐oxide‐free organic solar cells yield an enhanced light harvesting with a power conversion efficiency of 16.1%. Hot‐electron emission approach is proposed to recycle the energy of surface plasmon polaritons (SPPs) in photovoltaics by combining the transparent silver‐based plasmonic metal electrode (A‐PME) with a luminescent organic emitter. The nonradiative SPP damping in A‐PMEs is drastically restrained, achieving efficient organic solar cells with a power conversion efficiency of over 16%.