论文标题
狭窄金属毛细血管中波导模式的衰减
Attenuation of waveguide modes in narrow metal capillaries
论文作者
论文摘要
充满罕见等离子体的波导中激光脉冲的传递是激光韦克菲尔德加速的有前途的技术之一。固态毛细管可以精确地指导浓缩的脉冲。不管毛细管的物质如何，其壁在高强度激光脉冲的影响下的表现就像等离子体。因此，毛细管中的波导模式具有通用结构，仅取决于横截面的形状。由于毛细管半径与激光波长的比率很大，因此圆形毛细管中的模式与经典的TE和TM模式不同。此类模式的衰减长度比从经典公式获得的长度长两个数量级，并且适当半径的入射脉冲最多可以将其初始能量的98％传输到基本模式。然而，在任意横截面的毛细血管中找到本征是一个复杂的数学问题，尚待解决。
The channeling of laser pulses in waveguides filled with a rare plasma is one of promising techniques of laser wakefield acceleration. A solid-state capillary can precisely guide tightly focused pulses. Regardless of the material of the capillary, its walls behave like a plasma under the influence of a high-intensity laser pulse. Therefore, the waveguide modes in the capillaries have a universal structure, which depends only on the shape of the cross-section. Due to the large ratio of the capillary radius to the laser wavelength, the modes in circular capillaries differ from the classical TE and TM modes. The attenuation length for such modes is two orders of magnitude longer than that obtained from the classical formula, and the incident pulse of the proper radius can transfer up to 98% of its initial energy to the fundamental mode. However, finding eigenmodes in capillaries of arbitrary cross-section is a complex mathematical problem that remains to be solved.
