In order to investigate the process of optically triggered discharge formation, a model of ion space-charge formation based on classical plane electrodes and revised for a characteristic hollow-cathode discharge (HCD) configuration is proposed in this paper. The primary modified factor in our model is the penetrating electric-field parameter, which influences the ionization of trigger electrons and is calculated via particle simulation. Optical-trigger experiments are carried out using different voltages and under different seed-electron conditions, provided by two different photocathodes, Cu and Mg. The ion-accumulation rates calculated by our model are compared to the discharge-formation time, which is deduced from optical-trigger experiments. The results demonstrate that the process of positive space-charge formation is dominant in the HCD formation process or trigger delay, which is highly dependent on the seeding-electron density and applied voltage, and can therefore be quantitatively described by our model. Additionally, electron-beam generation is investigated by optically triggered HCD experiments on Mg- and Cu-photocathode-based devices. The results show that a more efficient trigger device is capable of generating an electron beam with higher amplitude and density.

为了研究光触发放电形成的过程，本文提出了一种基于经典平面电极并针对中空阴极放电（HCD）特征进行修正的离子空间电荷形成模型。我们模型中的主要修正因子是穿透电场参数，该参数会影响触发电子的电离并通过粒子模拟计算得出。由两个不同的光电阴极Cu和Mg提供的不同电压，不同种子电子条件下进行光触发实验。我们的模型计算出的离子积累速率与从光触发实验推导出的放电形成时间进行了比较。结果表明，正电荷形成过程在HCD形成过程或触发延迟中占主导地位，这高度依赖于种子电子密度和施加电压，因此可以用我们的模型定量描述。此外，通过在Mg和Cu光电阴极基器件上进行光触发HCD实验研究了电子束的产生。结果表明，更有效的触发装置能够产生具有更高振幅和密度的电子束。