Electron–ion coupling effects on radiation damage in cubic silicon carbide

Abstract

A two-temperature model has been used to investigate the effects of electron–ion coupling on defect formation and evolution in irradiated cubic silicon carbide. By simulating 10 keV displacement cascades under identical primary knock-on atom conditions, we find that the final displacement and the kinetic energy of the primary knock-on atom decrease rapidly with increasing electron–ion coupling strength. Moreover, by analyzing the number of peak defects, atomic and electronic temperatures, it is found that a higher number of peak defects is created for intermediate coupling strength due to the electronic temperature making a contribution to the disorder. Strong electron–ion coupling rapidly removes energy from the cascade, thus the number of peak defects is lower. Meanwhile, there is a non-monotonic trend in the relationship between the coupling strength and the time at which the temperature of atoms reaches the minimum. Furthermore, we discuss the mechanisms involved.