剪切磁场作用下低密度冷等离子体中的模式转换
Mode conversion in cold low-density plasma with a sheared magnetic field
摘要：
提出了一种理论，描述了两个电磁模式在冷低密度等离子体中的相互转换，特别是在离子响应可以忽略不计的高频极限。与经典的（Landau-Zener型）模式转换理论不同，低密度等离子体中的共振耦合区域并不一定很窄，因此耦合矩阵不能用一阶泰勒展开式近似，初始条件的设置也不同。对于强磁剪切的情况下，一个简单的方法被确定为准备一个双模波，使其转化为一个单模波进入高密度等离子体。该理论可用于聚变等离子体波功率输入的简化模型。特别是，应用设想仿星器的研究，其中两个电磁模式附近的等离子体边缘的相互转换是一个已知的问题。
英文摘要：
A theory is proposed that describes mutual conversion of two electromagnetic modes in cold low-density plasma, specifically, in the high-frequency limit where the ion response is negligible. In contrast to the classic (Landau--Zener-type) theory of mode conversion, the region of resonant coupling in low-density plasma is not necessarily narrow, so the coupling matrix cannot be approximated with its first-order Taylor expansion; also, the initial conditions are set up differently. For the case of strong magnetic shear, a simple method is identified for preparing a two-mode wave such that it transforms into a single-mode wave upon entering high-density plasma. The theory can be used for reduced modeling of wave-power input in fusion plasmas. In particular, applications are envisioned in stellarator research, where the mutual conversion of two electromagnetic modes near the plasma edge is a known issue.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
