Abstract:
Structural effects in nanocrystalline pyrochlore Y2Ti2O7
induced by high energy heavy ions
in a wide range of electronic stopping powers were studied by means of high-resolution transmission
electron microscopy and molecular dynamics simulation considering the grain size effect. Ion track
radii tend to saturate and even decrease at high electron stopping powers (>30 keV/nm) due to the
velocity effect. The threshold electronic energy loss to form amorphous tracks in nanoclusters and
large (>100 nm) crystals was estimated in the range 10.7–12.8 keV/nm. A strong size dependence
was observed for smaller (<50 nm) isolated nanocrystals, with smaller crystals being significantly
more sensitive to amorphous track formation
