First Principles Codes and Analysis Environments for Vacuum Electronics Simulation

The status of first principles modeling and simulation tools for vacuum electronics (VEs) is presented. These tools, when combined with parametric beam-wave interaction tools, comprise the suite of tools that enable the design and optimization of VE devices, such as RF amplifiers. Although many basic algorithms discussed in the article have been around for decades, the advances in electromagnetic and electrostatic particle-in-cell and meshless beam codes have revolutionized the VE device development process where first-pass design has become the standard. These include advances in emission physics, disparate-mesh geometry resolution, advanced boundary conditions, intercode operability, multimodule simulation pipelines, exploitation of computer hardware, optimization and sensitivity analysis, and advanced user simulation environments with multimodule pipelines. The article presents these advances.