電漿是物質的四個基本狀態之一（其他分別是固體，液體和氣體）。加熱氣體可游離它的分子或原子 (減少或增加它們的電子數目），從而將其變成電漿。電漿中包含帶電粒子：正離子和負電子或負離子。游 離可以由其他方法完成，例如用激光或微波產生器施加的強大的電磁場來達成。它引起的電離，是伴隨著 分子鍵的解離-如果存在的話。我們感興趣的是電磁波在一個穩定的電子-離子電漿中的傳播。這種研究 是在離子的運動可因質量太重而忽略不計且電子的溫度可忽略不計的近似下完成的。首先，我們研究電磁 波在沒有直流磁場下的行為。接下來，我們考慮波垂直於外部直流磁場的方向傳播的特殊情況。最後，我 們處理電磁波的波向量是平行於所施加的磁場的方向傳播的情況。

Plasma is one of the four fundamental states of matter (the others being solid, liquid, and gas). Heating a gas may ionize its molecules or atoms (reducing or increasing the number of electrons in them), thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions. Ionization can be induced by other means, such as strong electromagnetic field applied with a laser or microwave generator, and is accompanied by the dissociation of molecular bonds, if present. We are interested in electromagnetic (EM) wave propagation in a stationary electron-ion plasma, under the approximations that the ion motion may be neglected owing to heavy mass and the electron temperature may be neglected. As a first, we study the behaviors of EM wave under no DC magnetic field. Next, we consider the special case of waves propagating perpendicular to the DC magnetic field imposed externally. Finally, we treat the situation that the wave vector of the EM waves is parallel to the direction of the imposed magnetic field.