Electron Beam Source of Nanotube for Free Electron laser

自由电子激光用纳米管电子束源

• 批准号: 12650057
• 负责人: TSUNAWAKI Yoshiaki
• 金额: $ 2.18万
• 依托单位: Osaka Sangyo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650057/
• 关键词: carbon nanotube; multiwalled nanotube; field emission; field emitter; electron source; free electron laser; freeelectron laser

It is well known that an electron beam with low emittance and low energy spread is emitted from a tip of metal/semiconductor needle by field emission. These characters of the field emitter are favorable for a free electron laser (FEL). In this study carbon nano-tubes (CNTs) were synthesized by three methods of arc discharge, laser ablation and chemical vapor deposition (CVD). Some of them were investigated for the field emission experiment.A single multiwalled CNT on a W needle gave the current of 〜9 μA and a mass of entangled CNTs emitted electrons with current of 2.5 mA which is 〜100 times as high as that of usual W needle cathode. The SEM images of CNTs in pre-/post-experiment suggested that the entangled tubes were frayed by the high electric field and then electrons were emitted mainly from the tip of each CNT. Especially the entangles CNTs coated on a stainless tube with a very small amount of resin presented similar high current with a fluctuation of <4 %. However the current decreased to 〜600 to 40 μA when the electrodes with a hole at the center were set in order to extract the electron beam. It was attributed to the arrival of most of the elements to the first electrode. In the further studies, the geometrical optimum design of the electrodes will improve the current and the focusing property of the electron beam for FEL. Besides the field emission experiment, other remarkable results were obtained such as the first success of forming nano-products including CNT by ultraviolet laser of XeCl excimer and finding the superior transmission filter of polyethylene sheet including CNT in the far-infrared.

众所周知，场致发射是从金属/半导体针的尖端发射具有低发射度和低能量扩展的电子束。场致发射体的这些特性有利于自由电子激光器的发展。本研究采用电弧放电、激光烧蚀和化学气相沉积三种方法制备了碳纳米管。其中一部分用于场发射实验，单根多壁碳纳米管在钨针上的发射电流为10.9 μA，多根碳纳米管缠绕在一起的发射电流为2.5 mA，是普通钨针阴极的100倍。实验前后碳纳米管的SEM图像表明，纠缠管被高电场磨损，然后电子主要从每个碳纳米管的尖端发射。特别是用非常少量的树脂涂覆在不锈钢管上的缠结碳纳米管呈现出类似的高电流，波动<4%。当电极中心开孔引出电子束时，电流下降到600 ~ 40 μA。这归因于大部分元素到达第一电极。在进一步的研究中，电极的几何优化设计将有助于提高自由电子激光器的电流和电子束的聚焦性能。除了场致发射实验之外，还获得了其他显著的结果，例如首次成功地通过XeCl准分子的紫外激光形成包括CNT的纳米产品，以及发现包括CNT的聚乙烯片材在远红外中的上级透射滤光器。

项目成果

Y.Tsunawaki, M.Masuda, et al.: "Field Emission from a Mass of Entangled Carbon Nanotubes"Proc. of 23rd Int. FEL Conf. & 8th FEL Users Workshop. II47-II48 (2002)

Y.Tsunawaki、M.Masuda 等人：“大量缠结碳纳米管的场发射”Proc。

浅川誠, 綱脇惠章: "赤外線研究の過去・現在・未来-光源-"日本赤外線学会誌. 12. 6-11 (2002)

Makoto Asakawa、Keiaki Tsunawaki：“红外研究的过去、现在和未来 - 光源”日本红外学会杂志 12. 6-11 (2002)。

Y.Tsunawaki, M.Masaki, et al.: "Development of a Hybrid Helical Microwiggler with Four Poles per Period"IEEE J. Quantum Electron.. 39. 337-342 (2003)

Y.Tsunawaki、M.Masaki 等人：“Development of a Hybrid Helical Microwiggler with Four Poles per period”IEEE J. Quantum Electron.. 39. 337-342 (2003)

Y. Tsunawaki: "Free Electron Laser and its Applications in the Infrared"Soc. Res. of Light Appl./Vision, IEE Jpn.. LAV-01-15. 11-16 (2001)

Y. Tsunawaki：“自由电子激光及其在红外中的应用”Soc。

M. Asakawa and Y. Tsunawaki: "Sources in the Infrared"J. Jpn. Soc. Infrared Sci. Tech.. 12. 6-11 (2002)

M. Asakawa 和 Y. Tsunawaki：“红外线来源”J.