Effects of temperature and energy on the radiation response of GaAs/AlAs and GaAs/AlGaAs superlattices

In our previous study, we employed the ab initio molecular dynamics method to confirm experimental observations that the radiation resistance of the GaAs/AlAs superlattice is enhanced by the introduction of Ga to the AlAs layer. However, the radiation performances of GaAs/AlAs and GaAs/AlGaAs superlattices under the external conditions, such as temperature and higher radiation energy, remain unclear. The present results of ab initio molecular dynamics demonstrate that the temperature has slight effects on the threshold displacement energy of GaAs/AlAs and GaAs/AlGaAs superlattices. Moreover, there are generally more defects in the GaAs/AlAs superlattice at higher radiation energies, whereas the associated defects in the GaAs/AlGaAs superlattice generally remain unchanged. These results indicate that the GaAs/AlGaAs superlattice generally behaves more robustly at higher radiation energies, which is similar to the experimental observation and our previous study. The results reveal that the GaAs/AlGaAs superlattice is the more promising material for the current electronic and optical applications and will be beneficial to design highly radiation-resistant semiconductor superlattices for their applications as optical and electronic devices.