为了研究飞秒激光等离子体丝阵列对10 GHz微波传输特性的影响, 利用COMSOL软件构建了飞秒激光等离子体丝阵列与微波相互作用的数值仿真模型, 研究了等离子体丝阵列参数、等离子体特征参数、阵列层数对微波反射率和透射率的影响。数值结果表明: 当微波的电场方向垂直于等离子体丝轴向时, 无论微波相对于丝阵列的入射角如何变化, 丝阵列对微波完全没有影响。增加丝的直径或者电子数密度、减少阵列间距或者电子温度都可以使反射率增加, 透射率减小。光丝直径为500 μm, 阵列间距为1 mm的等离子体丝阵列对10 GHz微波反射率最大可达到0.88, 此时等离子体的特征参数为ne=1×1023 m-3, Te=0.3 eV。当增加丝阵列的层数时, 透射率减小, 最终趋近于0, 而反射率则保持不变。该研究结果对飞秒激光等离子体丝阵列屏蔽干扰微波具有重要意义。

In order to study the influence of femtosecond laser-produced plasma filaments array on the transmission characteristics of 10 GHz microwave, the numerical simulation model of the interaction between femtosecond laser-produced plasma filaments array and microwave was established by COMSOL. The effects of plasma filaments array parameters, plasma characteristic parameters and array layer number on the reflectance and transmittance of microwave were studied. The numerical results show that the plasma filaments array becomes transparent when the direction of the microwave electric field is perpendicular to the filaments axis, regardless of the incidence angle of the microwave with respect to the filaments. Increasing the filaments diameter or electron number density, or decreasing the filaments spacing or electron temperature will lead to the reflectance increasing and the transmittance decreasing. The maximum reflectance of 10 GHz microwave with plasma filaments array is up to 0.88 while the filaments diameter is 500 μm, the filaments spacing is 1 mm, and at this time the electron number density is 1×1023 m-3 and the electron temperature is 0.3 eV. When the number of filaments array layer number is increased, the transmittance decreases, eventually approaches zero, and the reflectance remains constant. The results of this study are helpful for the femtosecond laser-produced filaments array to interfere with microwave.