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electron emission Suppression from Cathode Surfaces of a Rod-Pinch Diode

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Chinese Physics Letters 2010年第5期27卷 160-163页

作者：高屹尹佳辉孙剑锋张众张鹏飞苏兆锋 Department of Engineering Physics Tsinghua University Beijing 100084 Northwest Institute of Nuclear Technology Xi'an 710024

The theory and method of suppressing electron emission from cathode surfaces is introduced, including increasing the emission threshold, reducing the surface electric field and shielding the emitted electrons. The stainless steel-graphite and Teflon-graphite composite cathodes are designed to test the above methods for a rod-pinch diode. The experiments are performed on the inductive voltage adder, and the results indicate that the Teflon-graphite composite cathode is effective in suppressing electron emission from the specified cathode surface, while the stainless steel-graphite composite cathode fails. The reasons are analyzed theoretically.

关键词： electron emission CATHODES DIODES SURFACES (Technology) ELECTRIC fields COMPOSITE materials STAINLESS steel ELECTRIC displacement

Diamond-based electron emission:Structure,properties and mechanisms

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Chinese Physics B 2024年第9期33卷 165-177页

作者： Liang-Xue Gu Kai Yang Yan Teng Wei-Kang Zhao Geng-You Zhao Kang-Kang Fan Bo Feng Rong Zhang You-Dou Zheng Jian-Dong Ye Shun-Ming Zhu Kun Tang Shu-Lin Gu School of electronic Science and Engineering Nanjing UniversityNanjing 210046China

Diamond has an ultrawide bandgap with excellent physical properties,such as high critical electric field,excellent thermal conductivity,high carrier mobility,*** with a hydrogen-terminated(H-terminated)surface has a negative electron affinity(NEA)and can easily produce surface electrons from valence or trapped electrons via optical absorption,thermal heating energy or carrier transport in a PN *** NEA of the H-terminated surface enables surface electrons to emit with high efficiency into the vacuum without encountering additional barriers and promotes further development and application of diamond-based emitting *** article reviews the electron emission properties of H-terminated diamond surfaces exhibiting NEA *** electron emission is induced by different physical *** advancements in electron-emitting devices based on diamond are also ***,the current challenges and future development opportunities are discussed to further develop the relevant applications of diamond-based electronemitting devices.

关键词： diamond negative electron affinity(NEA) PN junction electron emission

Electrophoretic Deposition of Oxide Nanoparticles for electron emission Enhancement

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Journal of Materials Science & Technology 2010年第11期26卷 1032-1036页

作者： Jong Rok Ahn Gil Seon Kang Hwack Joo Lee Chang Joon Park Korea Research Institute of standards and Science

Four oxide nanoparticles,such as yttrium oxide,lanthanum oxide,cerium oxide and zirconium oxide were coated on rhenium filaments by an electrophoretic deposition *** oxide coatings were examined by scanning electron microscopy,and electron emission characteristics of the oxide-coated rhenium were studied to find alternative oxide materials for replacing the hazardous thorium *** four oxides tested in this work,yttrium oxide and lanthanum oxide coated rhenium showed enhanced electron emission compared with an uncoated ***,lanthanum oxide coating evaporated too quickly in a vacuum chamber,and hence yttrium oxide was found to be the only alternative material for use in a routine mass *** optimum coating thickness of the yttrium oxide and lanthanum oxide was around 20 μm.

关键词： Electrophoretic deposition Oxide nanoparticles Scanning electron microscopy (SEM) electron emission

Experimental Study of electron emission Characteristics of a Surface Flashover Trigger in a Low Pressure Environment

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Plasma Science and Technology 2010年第6期12卷 748-752页

作者：胡上茂姚学玲陈景亮 State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University

Characteristics of electron emission induced by a surface flashover trigger device in a low-pressure trigger switch were investigated. A test method to measure the emitted charges from the trigger device was developed, and the factors affecting the emitted charges were analyzed. The results indicated that the major emitted charges from the trigger device were induced by surface plasma generated by surface flashover occurring on the trigger dielectric material. The emitted charges and the peak emission current increased linearly with the change in the trigger voltage and bias voltage. The emitted charges collected from the anode were affected by the gap distance. However, the emitted charges were less affected by the anode diameter. Furthermore, the emitted charges and the peak emission current decreased rapidly with the increase in gas pressure in a range from 0 Pa to 100 Pa, and then remained stable or changed slightly when the increase in gas pressure up to 2400 Pa.

关键词： emission charges electron emission emission current trigger switch surface flashover

Field electron emission from Caterpillar-Like Clavae Nano-Structure Carbon Thin Films

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Chinese Physics Letters 2010年第8期27卷 222-224页

作者：王丽军朱玉传王小平章诗刘欣欣李怀辉梅翠玉刘晓菲 College of Science University of Shanghai for Science and Technology Shanghai 200093

Nano-carbon films with large density of caterpillar-like clavae are synthesized by microwave plasma-assisted chemical vapor deposition using a mixture of methane and hydrogen gases on Mo film substrates. The films are characterized by Raman spectra, optical microscopy and field emission scanning electron microscopy. Field electron emission measurements of nano-carbon films are also carried out to show the turn-on field as low as 1.5 V/μm and the high current density of 2.2mA/cm^2 at electric field of ***/μm, the uniformly distributed emission site density from a broad well-proportioned emission area of about 4.0cm^2 is also obtained. The field- emission current density J versus macroscopic electric field E does not follow the original Fowler-Nordheim （F-N） relation since they are not well represented in the F-N plot by a straight line. A modified F-N relation is applied successfully to explain all the field-emission data observed for E 〈 6.0 V/μm.

关键词： electron emission NANOSTRUCTURED materials CARBON THIN films DENSITY PLASMA-enhanced chemical vapor deposition RAMAN effect

Mechanism of Secondary electron emission of Cu-Al-Mg Alloy

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Rare Metals 1995年第3期14卷 217-222页

作者：潘奇汉北京有色金属研究总院北京

The slices of Cu-Al-Mg alloys with thickness of 0.1mm were prepared. Some samples were activated at the temperature of 590°C and 620°C respectively. The secondary electron emission (SEE) factor (σ) was determined. The composition of surface and the electron binding energy were studied by means of XPS and AES. It is shown that the oxide mainly consisting of Al2O3 and MgO can be formed spontaneously at room temperature. This oxide layer exhibits lower electron binding energy, high σ and satisfactory stability.

关键词： Aluminum alloys electron emission Magnesium alloys

Slow highly charged ion O4+ induced electron emission from clean solid surfaces

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Slow highly charged ion O4+ induced electron emission from c...

A HfC nanowire point electron source with oxycarbide surface of lower work function for high-brightness and stable field-emission

第十三届全国核物理大会暨第八届会员代表大会

作者： Qayyum Abdul Institute of Nuclear Science and Technology Islamabad 44000Pakistan

The total electron emission yields following the interaction of slow highly charged ions (SHCI) O with different material surfaces (W,Au,Si and SiO) have been *** is found that the electron emission yields γ increase with the projectile velocity v and are roughly proportional to v in our lower energy ranges(2.5×10 m/s＜v=(2E/M)＜5.5×10m/s).

关键词： Slow highly charged ion(SHCI) electron emission electron stopping power

来源： cnki会议评论

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Nano Research 2020年第6期13卷 1620-1626页

作者： Shuai Tang Jie Tang Ta-wei Chiu Wataru Hayami Jun Uzuhashi Tadakatsu Ohkubo Fumihiko Uesugi Masaki Takeguchi Masanori Mitome Lu-Chang Qin National Institute for Materials Science TsukubaIbaraki305-0047Japan Graduate School of Pure and Applied Science University of TsukubaTsukubaIbaraki305-8857Japan Department of Physics and Astronomy University of North Carolina at Chapel HillChapel HillNC27599-3255USA

Electric field-induced point electron source is highly demanded for microscopy,spectroscopy,lithography,X-ray tubes,microwave devices,and data ***,the instability in emission current and requirement of ultrahigh vacuum have often limited its extensive *** we report a single-crystalline HfC nanowire with oxycarbide emission surface for stable electron emission at 50 nA with fluctuations less than 1%in a vacuum of 4×10^−7 *** emitter has a low work function of 2.5 eV measured by the field emission Fowler-Nordheim curve and it is in good agreement with density functional theory(DFT)*** energy spread is in a range of 0.21–0.26 eV with a corresponding reduced brightness 1.95×10^11−3.81×10^11 A·m^−2·sr^−1·V^−*** HfC nanowire with oxycarbide emission surface is a qualified candidate for the next-generation electron source with high brightness,large current,and low energy spread.

关键词： hafnium carbide oxycarbide nanowire electron emission field emission

Weak electron-Phonon Coupling and Unusual electron Scattering of Topological Surface States in Sb（111） by Laser-Based Angle-Resolved Photoemission Spectroscopy

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Chinese Physics Letters 2014年第6期31卷 182-185页

作者：谢卓晋何少龙陈朝宇冯娅伊合绵梁爱基赵林牟代翔何俊峰彭莹莹刘旭刘艳刘国东董晓莉俞理张君张申金王志敏张丰丰杨峰彭钦军王晓阳陈创天许祖彦周兴江 Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 Collaborative Innovation Center of Quantum Matter Beijing 100871 Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190

High-resolution laser-based angle-resolved photoemission （ARPES） measurements are carried out on Sb（111） single crystal. Two kinds of Fermi surface sheets are observed, which are derived from the topological surface states： one small hexagonal electron-like Fermi pocket around F point and the other six elongated lobes of holelike Fermi pockets around the electron pocket. Clear Rashba-type band splitting due to the strong spin-orbit coupling is observed to be anisotropic in the momentum space. Our super-high-resolution AFtPES measurements reveal no obvious kink in the surface band dispersions, indicating a weak electron-phonon interaction in the surface states. In particular, the electron scattering rate for these topological surface states is nearly a constant over a large energy window near the Fermi level that is unusual in terms of the conventional picture.

关键词： LASER pulse modes PHOTOelectron spectroscopy electron emission RASHBA effect RESEARCH ENERGY bands FERMI level electronIC structure