Ginzburg N S, Peskov N Y, Sergeev A S, Phelps A D, Konoplev I V, Robb G R, Cross A W, Arzhannikov A V, Sinitsky S L
Institute of Applied Physics, Russian Academy of Sciences, N. Novgorod, Russia.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 1999 Jul;60(1):935-45. doi: 10.1103/physreve.60.935.
The use of two-dimensional Bragg resonators of planar geometry, realizing two-dimensional (2D) distributed feedback, is considered as a method of producing spatially coherent radiation from a large sheet electron beam. The spectrum of eigenmodes is found for a 2D Bragg resonator when the sides of the resonator are open and also when they are closed. The higher selectivity of the open resonator in comparison with the closed one is shown. A time-domain analysis of the excitation of an open 2D Bragg resonator by a sheet electron beam demonstrates that a single-mode steady-state oscillation regime may be obtained for a sheet electron beam of width 100-1000 wavelengths. Nevertheless, for a free-electron maser (FEM) with a closed 2D Bragg resonator, a steady-state regime can also be realized if the beam width does not exceed 50-100 wavelengths. The parameters for a FEM with a 2D planar Bragg resonator driven by a sheet electron beam based on the U-2 accelerator (INP RAS, Novosibirsk) are estimated and the project is described.
采用平面几何结构的二维布拉格谐振器来实现二维分布反馈，被视为一种从大面积片状电子束产生空间相干辐射的方法。研究了二维布拉格谐振器在谐振器侧面开放和封闭两种情况下的本征模频谱。结果表明，开放谐振器比封闭谐振器具有更高的选择性。对片状电子束激发开放二维布拉格谐振器进行时域分析表明，对于宽度为100 - 1000个波长的片状电子束，可获得单模稳态振荡状态。然而，对于具有封闭二维布拉格谐振器的自由电子激光（FEM），如果束宽不超过50 - 100个波长，也可实现稳态状态。估算了基于U - 2加速器（俄罗斯科学院西伯利亚分院新西伯利亚国立大学）的片状电子束驱动的二维平面布拉格谐振器自由电子激光的参数，并描述了该方案。
