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arXiv 1302.7041physics.plasm-ph
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直流辉光放电和尘埃等离子体中自持振荡的机理

Mechanism behind self-sustained oscillations in direct current glow discharges and dusty plasmas

Sung Nae Cho

摘要:

本文对直流辉光放电中离子自持振荡的机理作了另一种解释。这样的描述是区别于流体模型,其中振荡归因于正反馈机制与粒子的光电离和电子从阴极的光电发射相关联提供的一个。在这里,振荡是由于离子和由其在边界电极处感应的表面电荷之间的相互作用而产生的。这一机理为直流辉光放电中电压-电流特性曲线的负阻区出现自持振荡提供了一个合理的解释。此外,这种替代性的描述为实验室等离子体中等离子体火球的形成提供了一个优雅的解释。已经发现,振荡频率随离子的表面电荷密度而增加,但其速率明显慢于其随电场而增加的速率。该机制还描述了尘埃等离子体中离子的自持振荡,这表明尘埃等离子体和直流辉光放电中的自持振荡涉及共同的物理过程。

英文摘要:

An alternative explanation to the mechanism behind self-sustained oscillations of ions in direct current (DC) glow discharges is provided. Such description is distinguished from the one provided by the fluid models, where oscillations are attributed to the positive feedback mechanism associated with photoionization of particles and photoemission of electrons from the cathode. Here, oscillations arise as consequence of interaction between an ion and the surface charges induced by it at the bounding electrodes. Such mechanism provides an elegant explanation to why self-sustained oscillations occur only in the negative resistance region of the voltage-current characteristic curve in the DC glow discharges. Furthermore, this alternative description provides an elegant explanation to the formation of plasma fireballs in the laboratory plasma. It has been found that oscillation frequencies increase with ion's surface charge density, but at the rate which is significantly slower than it does with the electric field. The presented mechanism also describes self-sustained oscillations of ions in dusty plasmas, which demonstrates that self-sustained oscillations in dusty plasmas and DC glow discharges involve common physical processes.

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。

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