Path-dependent electronic stopping for self-irradiated silicon
摘要
The experimentally validated real-time time-dependent density-functional theory (rt-TDDFT) provides a robust framework for studying electronic stopping. Accurate predictions of this directionally sensitive phenomenon are essential for various active research areas and applications, especially in semiconductors. Here we present a path-dependent model of electronic stopping in self-irradiated silicon in the keV-MeV regime. We find a linear relationship between electronic stopping and the mean electron density using rt-TDDFT calculations, performed with the Qball code, along six channels and three incommensurate trajectories. Using this, the model predicts electronic stopping as a function of the local ground-state electron density and the projectile velocity Se(v, ρ). Our model accurately describes the electronic energy losses along any trajectory, from channels to regions of higher electron density, including the random trajectories measured experimentally. In addition, we provide a comprehensive overview of rt-TDDFT calculations of electronic stopping in self-irradiated silicon, including a detailed description of the requirements of pseudopotentials in all kinematic regimes.