Electron-ion coupling effects on radiation damage in cubic silicon carbide.

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.