Plasma devices, as well as some astrophysical objects, are often characterized by the presence of the counterstreaming flows of electrons and positively charged particles in the plasma. In such diodes, more than one stationary solution is possible for the same set of diode parameters. In this paper, we have studied the stability of the most complex solutions, which are characterized by the presence of the potential barriers for both electrons and ions in the plasma gap. It was discovered that there exists a threshold for the value of the electron current, above which the solutions become unstable with respect to small perturbations. In this case, the solutions with nonlinear oscillations appear in the diode instead of stationary solutions. The period of these oscillations is compared to the average time of ion flight across the plasma gap. The features of time-dependent solutions have been studied. In particular, it is found that the electron current passing through the diode in the course of oscillations exceeds that corresponding to the steady states.

中文翻译：

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电子和离子反向流动的二极管中振荡模式的发生

等离子体装置以及一些天体物理物体的特征通常在于等离子体中存在电子和带正电粒子的逆流。在此类二极管中，对于相同的一组二极管参数，可能有不止一种固定解决方案。在本文中，我们研究了最复杂溶液的稳定性，其特征是等离子体间隙中存在电子和离子的势垒。发现电子电流值存在一个阈值，高于该阈值，解决方案对于小扰动变得不稳定。在这种情况下，二极管中出现非线性振荡解而不是稳态解。将这些振荡的周期与离子穿过等离子体间隙的平均飞行时间进行比较。已经研究了依赖于时间的解的特征。特别地，发现在振荡过程中通过二极管的电子电流超过对应于稳态的电流。