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	High Photocurrent Density and Continuous Electron Emission Characterization of a Multi-Alkali Antimonide Photocathode 期刊论文 OAI收割 ELECTRONICS, 2020, 卷号: 9, 期号: 12 作者: Dai, Jun; Ding, Yikun; Ruan, Cunjun; Xu, Xiangyan; Liu, Hulin \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2021/01/15 continuous high current density emission nonuniformity emission nonlinear emission built-in electric field
	High current density photocathode for CW terahertz photoconductive vacuum devices 期刊论文 OAI收割 Vacuum, 2020, 卷号: 180 作者: Dai, Jun; Ruan, Cunjun; Xu, Xiangyan; Liu, Hulin; Ding, Yikun \| 收藏 \| 浏览/下载：36/0 \| 提交时间：2020/08/21 Multi-alkali photocathode Continuous wave High current density emission Thermal conductivity Terahertz photoconductive vacuum device
	The synthesis and field emission property of carbon nanotubes on carbon fibers substrate (EI CONFERENCE) 会议论文 OAI收割 Technical Digest of the 20th International Vacuum Nanoelectronics Conference, IVNC 07, July 8, 2008 - July 12, 2008, Chicago, IL, United states Leyong Z.; Weibiao W.; Jingqiu L.; Yuxue X.; Da L.; Song C.; Haifeng Z. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Using ferrocene as catalyst precursor C2H2 as carbon source carbon nanotubes (CNTs) with uniform density were synthesized on carbon fibers substrate by floating catalyst method. The morphology and microstructure were characterized by field emission scanning electron microscope (FESEM) and high-resolution transmission electron microscopy (HRTEM). The observation showed that the length of CNTs is about 2 m the average space between adjacent CNTs is about 300 nm and the diameter of CNT is about 45 nm. The less dense "short and stubby" aligned CNTs films should have good electron field emission characteristics. The results of field emission showed that the emission current of CNTs/carbon fibers was 5 A at the field of 2.5 V/m and the emission current can be 280 A with a field of 7 V/m (the specimen area is 0.25 cm2 and the distance between cathode and anode is 200 m). The calculation based on the F-N plot indicated that the field enhancement factor of CNTs tip is 499122. Using the conductivity and chemical stability of carbon fibers and the uniform and sparse density distribution of CNTs on carbon fibers substrate the tip predominance of carbon nanotubes can be exerted and simultaneously the effect of screening effects between adjacent carbon nanotubes on the field emission performance can also be effectively decreased. The CNTs synthesized on carbon fibers substrate has many predominances for the fabrication of cold cathode devices. For example using the removability of carbon fibers the cathode of CNTs/carbon fibers can be arbitrarily moved enlaced or combined to form different patterns and the cathode of CNTs/carbon fibers can be also fabricated in large size. Therefore CNTs/carbon fibers may have potential application in field emission displays.
	Fabrication and electron emission of carbon microtubes (EI CONFERENCE) 会议论文 OAI收割 Technical Digest of the 18th International Vacuum Nanoelectronics Conference, IVNC 2005, July 10, 2005 - July 14, 2005, Oxford, United kingdom 作者: Liu L.; Liu L.; Wang W.; Wang W. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 Carbon nanotubes have been attracting attention because of their unique physical properties and their application potential for field emission cathode. Carbon nanotubes possess the following properties favorable for field emission material such as a high aspect ratio and sharp tip high chemical stability high mechanical strength stable at high temperature. Some research works on carbon nanotubes field emitter and field emission display have been reported. Here a kind of carbon microtubes and its field emission properties are introduced. They have some different properties with carbon nanotubes and the density is lower than carbon nanotubes bundles. These carbon microtubes are directly synthesized by liquidoid epitaxy method on silicon substrates at low temperature. The field emission properties of carbon microtubes are reported too. Carbon microtubes film is synthesized in liquid by electrolysis. The graphite plate is as anode and n-silicon substrate with resistivity of 4-8 cm is as cathode. The electrolysis current is about 5-8mA/cm2 and applied voltage is 800-1500V. Temperatures of the methanol base solution is maintained at 60C in process of deposition of carbon microtubes. Carbon microtubes film is observed by scanning electron microscopy(SEM) as shown in fig.1(a b). The wall's thickness of carbon microtube is about 60nm. The diameter of carbon microtube is about 0.8 m. Raman spectrum of carbon microtubes film shows the two peaks at 1342and 1560cm-1. The field emission properties of carbon microtubes are measured in high vacuum chamber(10-5Pa). The emission area of carbon microtubes is 0.5cm 0.5cm. The threshold of field emission of the carbon microtubes film is about 3.6V/ m. Field emission property of carbon microtubes film is shown in fig.2. Another when the electric field between anode and cathode is 10V/ m the electric field distribution on single carbon microtube is also given after calculation according to electric field theory. Fig 3 shows that electric field distribution vertical section on the of single carbon microtube top with 2 m of highness. These results may help us to understand field emission properties of carbon microtubes. According to research results it is found that liquidoid synthesis is simple method to produce carbon microtubes cold cathode material and the carbon microtubes have better field emission properties. 2005 IEEE.
	High-power InGaAs VCSEL's single devices and 2-D arrays (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices for Optical Communications, November 7, 2005 - November 10, 2005, Shanghai, China 作者: Sun Y.; Wang L.; Wang L.; Wang L.; Liu Y. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 We report on bottom-emitting vertical-cavity surface-emitting lasers (VCSEL's) and laser arrays providing high output powers in the 980-nm wavelength regime. Single devices with active diameters of 500 m show high output powers of 1.95 W at room temperature. Its threshold current is 510 mA and the maximum spatially averaged optical power density is 0.93 kW/cm2. A 16 elements array with 200m aperture size (250m center spacing) of individual elements shows a CW output power of 1.21 W at room temperature resulting in a average optical power density of 1KW/cm2. The threshold current of the array is 1.32A and the lasing peak wavelength is 981.9 nm. The distinction of emission spectrums between the single device and the array is discussed.