Role of Dynamic Screening in Energy Transfer to Lattice Atoms in Ion Tracks Formed in GaN under Electronic Stopping

Abstract

Multiscale simulation has shown that the formation of structurally modified tracks of swift heavy ions in GaN critically depends on the mechanism of dynamic screening of target atomic charges, which affects the efficiency of energy transfer from the excited electron subsystem to the atomic lattice. Using lead ion irradiation as an example, the formation of extended tracks with an amorphous core containing nanoscale cavities filled with nitrogen is demonstrated, in agreement with experimental results. In the defect halo surrounding the core, stable edge dislocations are formed, preventing recrystallization of the amorphous region during track cooling.