Applied particle-in-cell simulation in the design of excimer laser diode

The electron beam pumped excimer laser is a competitive candidate for inertial confinement fusion driver. In the excimer laser system, the diode serves as the core component, for its efficiency and reliability of the diode directly impact the laser's lifespan and electro-optical conversion efficiency. But there are no mature design standards for diodes, and many crucial designs rely on researchers' work experience. Particle-In-Cell Simulation is an efficient method to solve that problem. This article presents the mathematical and physical equations governing the transport of electron beams in the vacuum space of a diode, and discusses the application of Particle-in-Cell (PIC) simulation in the design of semiconductor laser diodes. It concludes that the use of PIC simulation allows for the calculation of the trajectory of electron beams, as well as the energy and angular distributions of the beams reaching the anode. Based on the simulation results, the diode can be optimized. It is found that efficient transportation of electrons to the anode surface can be achieved even without the use of guiding magnetic fields, though a drawback is the relatively large angle and dispersed energy distribution of the electron beams reaching the anode. The research offers insights for the efficient design of diodes.