Effects of electron temperature on the ion extraction characteristics in a decaying plasma confined between two parallel plates

Abstract

In this paper, a one-dimension particle-in-cell (PIC) code (EDIPIC) is employed to simulate the parallel-plate ion extraction process under an externally applied electrostatic field, focusing on the analysis of the influence of the initial electron temperature on the extracted ion fluxes to the metal plates during the ion extraction process. Compared with previously published results, the plasma oscillations on a timescale of the electron plasma period, and the excitation of the ion acoustic rarefaction waves resulting from the plasma oscillations originating from both the negative and positive electrodes, are studied for the first time. The modeling results show that both the negative and positive extractors can collect ions due to the plasma oscillations and the propagation of the ion acoustic rarefaction waves. With the increase of the initial electron temperature achieved by keeping other parameters unchanged, on the one hand, both the ion speed and flux to the negative and positive plates increase, which leads to a significant decrease of the ion extraction time, while on the other hand, the ion flux to the positive plate after the formation of a Child-Langmuir sheath is much more sensitive to an increase of the initial electron temperature than that to the negative plate. The PIC simulation results provide a deeper physical understanding of the influence of the initial electron temperature on the characteristics of the entire ion extraction process in a decaying plasma.

Analysis and particle-in-cell simulation on the similarity relation during an ion extraction process

“…Under the subsonic sheath expansion condition, the IRW can accelerate the ions in the bulk plasma to the sheath and brings considerable ion flux to both the positive and negative electrodes, as shown in figure 1(d). In addition, our modelling results show that the higher the electron temperature is, the more ions will be accelerated in the bulk plasmas [3].…”

“…The PIC modelling results revealed the spatiotemporal evolutions of the ion number density (n i ) under the conditions of supersonic and subsonic sheath expansions, as shown in figures 1(c) and (d), respectively [3]. It is seen clearly that, besides the sheath expansion, the IRW propagation may influence SPLG-2021 Journal of Physics: Conference Series 2147 (2022) 012013 the non-equilibrium transport characteristics of the ion extraction process.…”

“…A parallel plate conductor configuration is employed in this section [2,3]. A barium plasma is generated and uniformly distributed between two parallel plates at t = 0.…”

“…The species collisions are neglected due to the low environment pressure which is on the magnitude of 10 -5 Torr. The detailed description on the simulation method can be referred to our previous paper, and the simulation parameters are listed in table 1 [3].…”

Enhancement of Electron Temperature under Dense Homogenous Plasma by Pulsed Laser Beam

“…The electron temperature is an important parameter in determining the classification of the plasma (thermal and non thermal) by comparing its values with the temperature of the ions inside the plasma. Therefore, the researchers focused on this parameter in order to change the values of electron temperature according to the requirements of practical applications such as including nuclear fusion, plating operations and in industrial applications (1,2,3).There are several methods for heating plasma and varying the electron temperature values such as, applying a magnetic field or interacting by a laser beam with plasma (4,5,6,7).The process of energy absorbing of the laser beam occurs by inverse bremsstrahlung (IB). The (IB) process refers to absorb the energy of the photons by plasma electrons and gaining energy leads to heating the plasma and raising the temperature of the electrons.…”