Crystallization Instead of Amorphization in Collision Cascades in Gallium Oxide.
Junlei Zhao, Javier García Fernández, Alexander Azarov, Ru He, Øystein Prytz, Kai Nordlund, Mengyuan Hua, Flyura Djurabekova, Andrej Kuznetsov
Author Information
Junlei Zhao: Southern University of Science and Technology, Department of Electronic and Electrical Engineering, Shenzhen 518055, China.
Javier García Fernández: University of Oslo, Department of Physics and Centre for Materials Science and Nanotechnology, P.O. Box 1048 Blindern, N-0316 Oslo, Norway.
Alexander Azarov: University of Oslo, Department of Physics and Centre for Materials Science and Nanotechnology, P.O. Box 1048 Blindern, N-0316 Oslo, Norway.
Ru He: University of Helsinki, Department of Physics and Helsinki Institute of Physics, P.O. Box 43, Helsinki FI-00014, Finland.
Øystein Prytz: University of Oslo, Department of Physics and Centre for Materials Science and Nanotechnology, P.O. Box 1048 Blindern, N-0316 Oslo, Norway.
Kai Nordlund: University of Helsinki, Department of Physics and Helsinki Institute of Physics, P.O. Box 43, Helsinki FI-00014, Finland.
Mengyuan Hua: Southern University of Science and Technology, Department of Electronic and Electrical Engineering, Shenzhen 518055, China.
Flyura Djurabekova: University of Helsinki, Department of Physics and Helsinki Institute of Physics, P.O. Box 43, Helsinki FI-00014, Finland.
Andrej Kuznetsov: University of Oslo, Department of Physics and Centre for Materials Science and Nanotechnology, P.O. Box 1048 Blindern, N-0316 Oslo, Norway.
Disordering of solids often leads to amorphization, but polymorph transitions, facilitated by favorable atomic rearrangements, may temporarily help to maintain long-range periodicity in the solid state. In far-from-equilibrium situations, such as atomic collision cascades, these rearrangements may not necessarily follow a thermodynamically gainful path, but may be kinetically limited. In this Letter, we focus on such crystallization instead of amorphization in collision cascades in gallium oxide (Ga_{2}O_{3}). We determine the disorder threshold for irreversible β→γ polymorph transition and explained why it results in elevating energy to that of the γ polymorph, which exhibits the highest polymorph energy in the system below the amorphous state. Specifically, we demonstrate that upon reaching the disorder transition threshold, the Ga sublattice kinetically favors transitioning to the γ-like configuration, requiring significantly less migration for Ga atoms to reach the lattice sites during postcascade processes. As such, our data provide a consistent explanation of this remarkable phenomenon and can serve as a toolbox for predictive multipolymorph fabrication.
