论文部分内容阅读
提出了一种用于Smith-Purcell器件的介质加载金属光栅周期慢波结构.通过采用本征函数法和单模近似法求解了介质加载金属光栅的“热”色散方程,在同步点得到了注-波互作用的一阶和二阶增长率,分析了光栅槽宽和槽深对色散特性的影响,并研究了电子注参数及其与光栅表面距离等主要参数对增长率特性的影响.结果表明:通过介质加载金属光栅有利于减弱色散,随着介质相对介电常数、槽宽度以及深度的增大,色散曲线变平缓且向低频区移动;当电子注参数变化时,一阶增长率曲线从整体上粗略地描述增长率变化趋势,二阶曲线则更精细地描述增长率相应值的变化.利用软件MAGIC对该结构的色散特性进行了二维模拟,模拟结果与理论计算值符合良好.
A medium-loaded metal grating periodic slow-wave structure for Smith-Purcell devices is proposed. The “hot” dispersion equation of the metal-loaded metal grating is solved by using the eigenfunction method and the single-mode approximation method, Note - the first and second order growth rates of wave interactions, the influence of groove width and groove depth on dispersion characteristics is analyzed, and the effect of the main parameters such as electron injection parameters and grating surface distance on the rate of growth is studied The results show that the dispersion of metal grating is beneficial to the reduction of chromatic dispersion, and the chromatic dispersion curve is gentle and moves to the low frequency region with the increase of relative dielectric constant, groove width and depth of the medium. When the parameters of electron injection change, The rate curve roughly describes the change trend of the growth rate as a whole while the second-order curve describes the change of the corresponding value of the growth rate more finely. The two-dimensional simulation of the dispersion characteristic of the structure is performed by using the software MAGIC. The simulation results are in good agreement with the theoretical values good.