Abstract: The geometric model of laser plasma channel (LPC) guiding electromagnetic pulse (EMP) in a finite electromagnetic field is created; when LPC is in lossy gas the propagation properties of the normal modes of LPC guiding EMP are studied; and then the wave equation of longitudinal electromagnetic field and the relationship between transverse and longitudinal electromagnetic field in anisotropic medium are derived under the generalized cylindrical coordinate system. By applying the boundary conditions of electromagnetic fields, the strict characteristic equation of mode propagation for LPC guiding EMP is deduced, and the effects of plasma parameter, surrounding material and external magnetic field on propagation are discussed. The results show that the propagation properties of magnetized LPC guiding EMP are easy to be controlled compared with those without external magnetic field or an infinite external magnetic field applied.

Key words: Finite magnetic field, Laser, Electromagnetic pulse, Characteristic equation, Propagation properties

摘要： 分析了有限磁场中激光等离子体通道周围为有耗气体介质时激光引导电磁脉冲传播的一般模式的传播特性，建立了有限磁场中激光等离子体通道引导电磁脉冲的几何模型，导出了广义柱坐标系下各向异性介质中纵向场所满足的波动方程及纵向场与横向场的关系。利用边界条件给出了有限磁场中激光引导电磁脉冲传播模式的严格特征方程，重点讨论了传播常数随等离子体参数、周围介质参数和外加磁场的变化。结果表明，有限磁场中激光引导电磁脉冲的传播特性比无磁场或外加无穷大磁场时更具有可控性。

关键词: font-family: 方正宋三简体, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, mso-bidi-language: AR-SA, mso-font-kerning: 1.0pt, mso-bidi-font-size: 12.0pt, mso-ascii-font-family: 'Times New Roman', mso-hansi-font-family: 'Times New Roman', mso-bidi-font-family: 'Times New Roman'">有限磁场；激光；电磁脉冲；特征方程；传播特性