电磁波在不均匀磁化等离子体中的吸收

本文讨论了不均匀磁化等离子体片对圆极化电磁波、异常模电磁波的吸收,计算了不同条件下衰减率.计算表明,当电磁波的频率接近电子碰撞频率时,磁等离子体对电磁波的吸收达到最大值.当入射电磁波的频率很低时,不均匀磁化等离子体中碰撞对雷达波的吸收非常小.当入射电磁波频率较高时,等离子体的碰撞对入射电磁波的衰减很有效.在磁场对电磁波衰减率的影响上,对右旋电磁波,磁场变大,衰减率曲线的峰值向较低的碰撞频率方向移动,且衰减率减小.而对左旋电磁波,磁场变大,衰减率曲线的峰值向高的碰撞频率方向移动,且衰减率也增大.同时,我们发现在一定条件下,磁场使电磁波的有效吸收带宽变宽.此时,等离子体对电磁波的吸收也最大.特别是当入射电磁波的频率较低时这一特性更显著.

Research on the Absorption of EM-Wave by Inhomogeneous Magnetized Plasmas

In this paper,the absorption of circularly polarized and the X-mode EM-wave by inhomogeneous magnetized plasmas is discussed,and the attenuations are calculated under different conditions.The results illustrate that the collisional absorption have a maximal value when the collision frequency is near the EM-wave frequency.Meanwhile,the absorption is very poor when the EM-wave frequency is small.The absorption is efficient with a high incident EM-wave frequency.We also find out that the magnetic fields have an influence upon the attenuations of EM-wave.For the right circularly polarized EM-wave,the peaks of the attenuation curves move to the low collision frequency,and the attenuations reduce when the magnetic field grows.For the left circularly polarized EM-wave,the peaks of the attenuation curves move to the high collision frequency,and the attenuations becomes large when the magnetic field reduces.And we find out that the effective frequency band width of absorption can be broadened under some conditions while the absorption of EM-wave have a maximum.This characteristic is remarkable when the EM-wave frequency is low.