振幅螺旋变化周期Wiggler场自由电子激光器增益的研究

本文研究了振幅螺旋变化周期Wiggler场自由电子激光器的增益特性。利用逐阶近似分析法解析了相对论电子在这种Wiggler场中运动的洛仑兹力方程和能量方程,获得了这种激光器的增益表达式。在给定其物理参数情况下,计算了这种激光器的增益。结果表明,激光器增益比同等物理参数下振幅恒定周期Wiggler场自由电子激光器有较明显提高;恒定振幅     

永磁Wiggler磁场的设计和小周期数装置的实验

Wiggler磁场是自由电子激光器的重要组成部分。根据计算分析和自由电子激光器的总体设计要求,提出了Wiggler磁场的设计考虑。研制出小周期数装置,在改变磁隙、周期、磁块尺寸以及材料的情况下进行了测量,同时测量了磁场的正弦分布。结果表明,设计并研制的小周期数Wiggler磁场满足总体要求,可用于自由电子激光器。     

振幅螺旋变化的周期wiggler场自由电子激光器增益研究

本文用逐阶近似法分析了相对论电子洛仑兹力方程和能量方程,获得了振幅螺旋变化的周期wiggler场自由电子激光器的增益表达式。结果表明,这种激光器的增益比采用恒定振幅周期wiggler场自由电子激光器有较明显的提高。     

振幅压缩态的P表示特性

振幅压缩志是与普通压缩相干态性质不同的另一类非经典光场态,由于它具有比后者更小的光子数起伏而在最近受到重视。本文应用文献中最新提出的非经典在光场的判据,讨论了振幅压缩态的P表示特性。我们得到了用来确定振幅压缩态P表示特性的特征函数具有如下形式:     

振幅压缩态的P表示特性

最近预言的振幅压缩态由于可以具有比压缩相干态更小的光子数噪声而受到重视。本文用文献中最新提出的非经典光场的判据讨论了振幅压缩态的P表示特性,发现它本质上与光子数本征态一样,也是通过复平面一点上的奇异性来表现其非经典性的。     

室温脉冲螺旋Wiggler磁体和大电流脉冲电源的研究

本文研究了适用于自由电子激光的室温脉冲螺旋Ｗｉｇｇｌｅｒ磁体，对其设计构思、磁场特性和设计参数进行了分析和计算．作者在文中还研究并设计了螺旋Ｗｉｇｇｌｅｒ磁体的大电流宽脉冲供电电源；分析了脉冲电流的时间特性对产生自由电子激光的影响程度．     

室温脉冲螺旋Wiggler磁体和大电流脉冲电源的研究

本文研究了适用于自由电子激光器的室温脉冲螺旋Ｗｉｇｇｌｅｒ磁体，对其设计构思、磁场特性和设计参数进行了分析和计算。作者在文中还研究并设计了螺旋Ｗｉｇｇｌｅｒ磁体的大电流宽脉冲供电电源；分析了脉冲电流的时间特性对产生自由电子激光的影响程度。     

一种按照指数函数相对振幅分布的新型周期DGS微带线设计

设计了一种新型一维周期接地缺陷结构(DGS)微带线。与传统的周期均匀DGS单元微带线不同的是,这种改进的周期DGS平面电路是一种补偿的微带线,每个DGS单元尺寸是不同的,尺寸按照指数函数e1/n(n为正整数)的相对振幅变化。本文设计了一个均匀周期DGS平面电路和两个改进的周期DGS平面电路,测量结果显示改进的周期DGS平面电路能够更好地抑制波纹和增大带阻带宽。     

二元周期序列的有理分数表示

密码学是在对信息不断进攻和防御的基础下发展进步的。为了抵抗代数攻击和相关攻击,通常使用非线性移位寄存器(NFSR)生成序列,其中反馈移位迭代寄存器(FCSR)是目前研究比较完善的一类NFSR.通过FCSR引入若干进位寄存器,实现了有理分数2-adic展开序列的快速生成。     

行波磁场摆动器产生自由电子激光的初步研究

在一定放置的线圈中通以正弦交流电时,其附近空间就会产生一个正弦行波磁场,磁场的极距和行波的速度都可以通过输入的频率加以调节。相对论性电子在这种摆动器中的散射波长比较短,而能量因子值可以变,这既有利于向短波长方向发展,又有助于自由电子激光器的小型化。     

Three-dimensional motion of electrons in combined realistic helical wiggler with axial guide field for free-electron laser

3-D motion of electrons with on-axis and off-axis guiding centers in realistic helical wiggler and axial guide field is analysed. It is found that purely helical orbits couldnot exist for the electrons with off-axis guiding centers, except for those with on-axis guiding centers. Perturbation solutions of the electron's velocity and orbit averaged over the cyclotron angle are derived. Our calculations indicate the divergence of the electron orbits near resonance.     

Equivalence of periodic magnetic field to uniform magnetic field in electron beam focusing

The general solution of the electron trajectory equation in a periodic magnetic field is derived in the form of series expansion, assuming laminar electron flow and small perturbation. It is concluded that if the cathode is not very heavily immersed in a magnetic field, beam focusing by a periodic magnetic field would be almost equivalent to that by a uniform magnetic field except near the unstable region. Under these restrictions, each focusing system would give almost the same beam ripple (in magnitude and phase) under the same injection conditions into the focusing system. It is also found that the first stable region of beam perturbation in the periodic magnetic field becomes narrower as the flux threading the cathode increases or the period of the magnetic field decreases, as far as linearization of the path equation is possible.     

Formation of a periodic magnetic field by a sequence of rings with different magnetic and electric properties

The electrodynamic analysis of the topography of magnetic fields generated in a spatially periodic structure is performed. The structure is a solenoid containing periodically spaced rings made from materials with different electric and magnetic properties. The system of equations relating the amplitudes of spatial harmonics of the magnetic field is derived and numerically analyzed. Dependences of the amplitudes of longitudinal and transverse components of the modulated magnetic field on the ring dimensions, the current frequency, and the magnetic and electric properties of the ring materials are investigated. The field amplitudes obtained during the complete electrodynamic analysis are compared with the amplitudes of a periodic magnetic field obtained in the impedance approximation.     

电子在双曲函数摇摆场和轴向导引场中的运动分析

本文用扰动法来分析电子在具有双曲函数型摇摆场和轴向导引场中的离轴运动轨道和速度。发现了电子运动存在着丰富的回旋谐振频谱，有基波即磁共振和高次谐波回旋谐振和反回旋谐振，并且存在分数谐振和反谐振。     

Gyromonotron with an axial combining periodic magnetic field

On the base of the reference (1), making use of the linear kinetic theory, gyromonotron with an axial combining periodic magnetic field has been analysed in detail. The formulas of electron beam to wave interaction power, frequency shift and starting current, etc. have been derived.     

相对论电子在周期磁场中的辐射频谱

分析了相对论电子在空间周期磁场中的运动轨迹.在一定条件下,电子在垂直原始入射方向上的运动是简谐的,利用谐振子模型求出了它的辐射频谱和频宽;最后讨论了运动的非谐性.得到辐射频谱分布将是与电子的初速度、磁场强度有关.     

STUDY OF GYROMONOTRON WITH A COMBINING PERIODIC MAGNETIC FIELD AND A COAXIAL CYCLOTRON ELECTRON BEAM

On the basis of a work of Wu Jianqiang et al.(1987),by making use of the linear kinetictheory,the gyromonotron with a combining periodic magnetic field and a coaxial cyclotron electron beam hasbeen analysed in detail.And the formulas of the electron beam to wave interaction power,frequency shift andstarting current,etc.have been derived.     

对称强磁场产生装置设计及磁场仿真

在对称线圈上施加强脉冲电流,在脉冲电流的激励下,线圈中产生感应脉冲磁场,从而实现同极性磁场撞击.在撞击过程中,磁能会以一种波的形式激发出去,从而产生激磁波.激磁波是一种磁性波,其能量主要通过磁场的变化进行传递.利用有限元的方法对对称线圈的内部外部分别进行仿真,讨论并分析了磁场在空间和时间上的变化.