Physics of amorphization

The amorphization due to the ion impact after the crystalline to amorphous (CA) transition is evaluated by the long-range-order parameter. The CA transition occurred much later than the introduced energy is released, in the order of a few tens of picoseconds. Although the heating rate in a MD is much higher than the real system, calculation even found the reality of the presence of global phonons whose behavior is slowly and oscillatory. After the CA transition, if one observed the atomic distribution of damaged crystal it may appear just random. Nevertheless, if the post-annealing is applied to, some preparation may be progressing in the material for the recovery of damaged crystallinity during (T_HB <; T_A) and after (T_HB = T_A) the heating process, before the arrival of the longest limit of a MD (~ nanosecond). Namely, slight change proceeds in a long blackout tunnel until it will be observed as the so-called amorphous (uniformly distributed atoms in an area) state.