110GHz太赫兹波大气击穿阈值及最大传输能量密度

Air breakdown threshold and maximum transmitted energy density of 110 GHz terahertz waves

随着110GHz高功率太赫兹波功率容量的提升,其引起的大气击穿问题越来越受到重视。将若干等效电离参数表达式引入到电子雪崩密度方程中,计算了不同压强下的大气击穿阈值。结果表明,由Ali等效电离参数得到的110GHz击穿阈值与实验数据符合得很好。在此基础上,利用Ali等效电离参数对逃逸传输能量密度与太赫兹波振幅的关系进行了分析。结果表明,当太赫兹波振幅小于击穿阈值时,逃逸传输能量密度随功率密度的增加线性增加;当太赫兹波振幅大于击穿阈值时,逃逸传输能量密度随功率密度先减小后增大。

With the development of the power capacity of 110 GHz high-power terahertz waves, the air breakdown by 110 GHz high-power terahertz waves has drawn more and more attention. Several approximations of effective ionization parameters are introduced into the equation of the electron avalanche density, and the breakdown thresholds are calculated at different pressures. The results show that the breakdown thresholds from Ali effective ionization parameters agree very well with the experimental result. The dependence of transmitted energy density on the electric amplitude is also investigated using Ali effective ionization parameters. The results show that, the transmitted energy density increases with the power density linearly when the amplitude is lower than the breakdown threshold; but the transmitted energy density first increases with the amplitude and then decreases when the amplitude is larger than the breakdown threshold.