An ab initio molecular dynamics study on the threshold displacement energies in yttrium aluminum garnet

Abstract

Low-energy recoil events in yttrium aluminum garnet (YAG) were investigated by using ab initio molecular dynamics simulations. This work provided insights into understanding the defect formation processes and the resulting defect configurations. The threshold displacement energies (TDEs) of the lattice atoms and related defect structures were determined along specific directions. Both the TDEs and the production of defect structures showed great dependence on the orientation and atom type. The minimum TDEs are 42, 38, 41, and 19 eV for Aloct along [111], Altetra along [1¯11], Y along [001], and O along [111] directions, respectively. The O atoms exhibited smaller TDEs than the Al and Y atoms, indicating that the O-related defects are the main ones in YAG used under irradiation circumstances. These results are helpful for electronic and photoelectronic devices based on YAG under a radiation environment.