Multiscale three-dimensional simulations of charge gain and transport in diamond
Multiscale three-dimensional simulations of charge gain and transport in diamond
复制标题
金刚石中电荷增益和输运的多尺度三维模拟
DOI：
--
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
E. Muller
中科院分区：
文献类型：
--
作者：
D. Dimitrov;R. Busby;J. Cary;I. Ben;T. Rao;J. Smedley;X. Chang;J. Keister;Qiong Wu;E. Muller
最近提出了一种用于产生大电流、高亮度、低热发射率电子束的金刚石放大光电阴极的新概念，目前正在积极开发中。为了设计可靠和高效的钻石放大器阴极，需要详细了解具有多个能量和时间尺度的物理过程。我们在涡旋计算框架内建立了模型来模拟钻石中的二次电子产生和电荷输运，以便于研究所涉及的相关效应。这些模型包括用于产生电子-空穴对的电子和空穴的非弹性散射、弹性散射、声子散射和电荷杂质散射。我们描述了我们开发的集成模拟能力，并给出了电荷增益和收集效率作为初级电子能量和外加电场的函数的结果。我们将模拟结果与现有的实验数据进行了比较。模拟结果与从传输模式实验中观察到的电荷增益总体上是定性一致的，并使人们能够更好地理解收集效率的测量。
A promising new concept of a diamond-amplified photocathode for generation of high-current, high-brightness, and low thermal emittance electron beams was recently proposed and is currently under active development. Detailed understanding of physical processes with multiple energy and time scales is required to design reliable and efficient diamond-amplifier cathodes. We have implemented models, within the VORPAL computational framework, to simulate secondary electron generation and charge transport in diamond in order to facilitate the investigation of the relevant effects involved. The models include inelastic scattering of electrons and holes for generation of electron-hole pairs, elastic, phonon, and charge impurity scattering. We describe the integrated modeling capabilities we developed and present results on charge gain and collection efficiency as a function of primary electron energy and applied electric field. We compare simulation results with available experimental data. The simulations show an overall qualitative agreement with the observed charge gain from transmission mode experiments and have enabled better understanding of the collection efficiency measurements.