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1.
当调制电子束入射进空间等离子体时,由于电子束本征电磁场在非均匀等离子体中的散射(渡越辐射transition radiation)或者电子束的纵向约束性可以产生电磁波辐射.基于这两种辐射机制,研究了半无界调制电子束从航天器入射进平面分层各向同性非均匀空间等离子体产生的电磁波辐射.结果表明,由背景等离子体非均匀性产生的电磁波辐射强度高于由束的纵向约束性引起的辐射强度通过对电子束的适当调制,可以满足辐射电磁波在局部等离子体谐振区域的共振条件,从而增大辐射强度.研究结果可用于对主动空间等离子体试验数据的分析.  相似文献   

2.
等离子体加载波纹波导的色散方程   总被引:2,自引:0,他引:2  
本文在考虑离子通道及电子束注入后等离子体电子重新分布条件下,导得了填充等离子体波纹波导的注波互作用色散方程,并给出了不同条件下的具体表达式。研究表明,结果与不考虑离子通道相比有较大差异。  相似文献   

3.
本文建议用脉冲激光形成的高温等离子体作为高亮度电子束源,估算表明亮度可能比热电子枪高百万倍.这种电子束源也许会对电子显微术和自由电子相干辐射有用.  相似文献   

4.
在超短超强激光与固体薄膜靶相互作用研究中,实验上首次观测到了沿靶面方向发射的高能超热电子束.该电子束只有在等离子体电子密度标长较短的条件下才会出现.理论模拟表明,靶表面电磁场的约束作用是产生此电子束的主要原因.这一结果有助于加深对激光愤性约束聚变快点火实验中的锥靶物理过程的理解,并有潜在的应用前景.  相似文献   

5.
本文简述了当前国内外微细图形加工技术的各种方式;着重介绍了用电子束曝光、氯等离子体刻蚀工艺制作高质量亚微米铬掩摸版的工艺实验及条件选择,应用效果等;还提出了干法刻蚀过程中的安全防护措施及下步工作考虑。  相似文献   

6.
对等离子体填充扩展互作用振荡器进行了研究,通过CST软件研究了填充不同密度等离子体对Ka波段矩形耦合腔扩展互作用振荡器高频特性的影响,得到了通过改变等离子体密度与工作电压实现调节扩展互作用振荡器工作频率的方案.利用CST粒子工作室对其进行了粒子模拟分析,结果表明通过电子束电压和等离子体密度的共同调节,可使Ka波段扩展互作用振荡器实现34.14~37.99 GHz的调谐.  相似文献   

7.
本文描述了产生在软真空中的电子束及其特性,这种成本低廉的大功率电子束在微电子、光电子加工和等离子体化学方面有很大应用价值。文中给出了电子束的放电特性、强度空间分布和能谱的实测结果,对这种电子束的形成机理提出了新的见解。  相似文献   

8.
描述等离子体填充微波器件的技术背景。从分析关键技术出发,着重给出等离子体阴极电子枪、等离子体辅助电子束传输聚束、以及等离子体辅助注波互作用的概念设计。提出一种X波段等离子体填充返波管的实施方案。  相似文献   

9.
一种新型显示器件——电子束管平板   总被引:1,自引:1,他引:0  
本文对荷兰飞利浦公司研制的新型显示器件──电子束管平板作了较为全面的介绍,并比较了这种显示器件与电子束管、有源矩阵液晶显示和等离子体显示板等的性能。  相似文献   

10.
电子束与等离子体互作用产生的宽带微波辐射   总被引:1,自引:0,他引:1  
熊彩东  吴坚强 《电子学报》1995,23(10):160-163
近年来,电子束与等离子体互作用产生高功率宽带微波辐射,由于其具有可调谐等优点而受到国际上普遍关注,这一互作用过程的辐射机制目前大致分为等离子体辐射和电子束辐射两大类,本文在简介了有关实验情况后,对几种辐射机制,包括逆Compton散射,孤立子场中群聚电子的辐射,非线性等离子体电流引起的辐射等作了评述。  相似文献   

11.
The linearized fluid and Maxwell's equations are used to calculate the dispersion relation for the transverse magnetic modes of a partially filled, plasma-lined, cylindrical waveguide interacting with a relativistic electron beam. Both the plasma liner and the electron beam are assumed to be cold, and the system is immersed in an infinite axial magnetic guide field. The dispersion relation is then used to calculate the growth rate for the instability between the slow-wave modes (Trivelpiece-Gould modes) of the plasma guide and the slow-space charge mode of the electron beam. The calculation is done in the high-gain, strong coupling limit  相似文献   

12.
该文利用线性理论,对相对论环形电子注与环形等离子体互作用产生微波辐射进行了研究,在考虑有限磁场的基础上,利用“匹配场法”求得色散方程,重点分析了等离子体密度、厚度、外加磁场对等离子体切伦可夫脉塞注-波互作用的影响,并计算了各参量变化时的波增长率以及色散关系。  相似文献   

13.
On the basis of the reference [1], excitation of Cherenkov radiation with arbitrary azimuthal mode number by a thin annular relativistic electron beam in a plasma-filled dielectric-lined slow-wave waveguide is studied in this paper. A determinantal dispersion equation is obtained. This general dispersion equation is valid for arbitrary azimuthal mode number, and the growth rate of the wave is derived from it. Finally, the effects of the background plasma density on the dispersion relation, the background plasma density and the electron beam radius on the growth rate of the wave are presented. Formulas and results offerd in this paper are general, and are of particular value of reference to the beam-wave interaction in azimuthally unsymmetrical slow-wave waveguide.  相似文献   

14.
Theoretical studies of electron beam-plasma interactions have predicted the occurrence of amplifying waves having growth rates maximizing near to the electron plasma frequency. For the special case of an infinite beam interacting with a cold infinite plasma, an infinite growth rate is expected at the plasma frequency. In practice, the theoretical gain becomes finite if factors such as collisions or non-zero electron temperature are taken into account, or if the beam and plasma ore not both infinite. In this paper, beam-plasma interaction is investigated in planar geometry for both finite and infinite beams in an infinite, uniform, warm plasma. In the finite beam case, the question of appropriate boundary conditions to use at the beam edge arises. For cold plasmas, the Hahn approximation involving postulatian of an equivalent surface charge at the beam edge is usually applied. In the case of a warm plasma, it is unlikely that this approximation would describe accurately the plasma behaviour, though it may still be appropriate for the beam. Suitable boundary conditions are suggested, and computed curves are presented comparing the complex solutions of the resulting dispersion relation with the cold plasma solutions for the same geometry. For typical experimental conditions a substantial reduction of gain is indicated when non-zero electron temperature is taken into account.  相似文献   

15.
Under the condition of considering the plasma electrons redistribution and ion channel and the transverse oscillating of the beam after the REB incident, the dispersion equation of corrugated waveguide filled with plasma was obtained in this paper, its expressions under several conditions were also given. The results showed that whether consider these factors or not, the results would be quite different.  相似文献   

16.
本文在考虑等离子体厚度效应的情况上,详尽地推导了充填圆环状等离子体的圓柱波导中TM模慢电磁波的色散方程;利用相对论空间电荷波理论,导出了相对论电子注在轴向磁场引导下沿等离子体内表面传输时的空间电荷波方程;求得了电子注和慢空间电荷波相互作用的线性增益和频率漂移;讨论了等离子体厚度、密度对色散特性和互作用增益的影响。  相似文献   

17.
Space-charge wave propagation for periodic-electrostatically focused electron beams with nonuniform radial beam density distributions is the subject of this paper. The dispersion equation is obtained by solving a differential equation for the ac electric potential inside the electron beam and by matching the solution at the boundaries. An approximate analytic solution and a digital computer treatment are described. The reduced plasma frequency obtained is expressed in terms of the focusing parameters and is compared with that of a Brillouin beam. A study of the differential equation involved suggests that there are certain ranges of system parameters ("forbidden" zones) for which no wave propagation is possible, that is, no space-charge mode can be supported there.  相似文献   

18.
A linear analysis is described on stabilities driven by an intense relativistic electron beam in an infinitely long, plasma-filled, and dielectric-lined circular waveguide immersed in a finite strength axial magnetic field. A dispersion equation is derived from the cold fluid theory and solved numerically. Beam-plasma instabilities due to interaction between beam modes and the Trivelpiece-Gould modes appear as well as the Cherenkov and the cyclotron Cherenkov instabilities. Parametric researches are carried out varying magnetic field strength, plasma density, and dielectric constant. Effects of a finite magnetic field and plasma filling are discussed in connection with the possibilities of using this system as a microwave radiation source.  相似文献   

19.
吴坚强  熊彩东 《电子学报》1996,24(6):25-28,33
本文利用线性理论,对相对论电子注与等离子体柱互作用产生微波辐射进行了研究,且考虑了纵向均匀磁场的作用。  相似文献   

20.
利用线性场理论,对填充环形等离子体的介质切伦可夫脉塞进行了详尽的分析;讨论了薄环形相对论电子注包围环形等离子体、处于环形等离子体之间和位于环形等离子体之内,这三种情况下的注波互作用,分别导出了其色散方程;并对色散方程直接进行了数值求解;求得了系统的截止频率、工作频率和波增长率,讨论了有关参数对它们的影响。  相似文献   

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