Molecular Dynamics Study of Defect Evolution Mechanisms in 3C-SiC for Quantum Technologies

The migration of point defects and formation of spin defects in 3C-SiC were investigated using molecular dynamics simulations, with migration barriers obtained from Nudged Elastic Band (NEB) calculations and finite temperature diffusivities evaluated using both mean square displacement (MSD) and jump frequency approaches. While both methods reproduce Arrhenius behavior, the jump frequency formulation exhibits improved statistical stability. Activation energies of 2.12~eV for carbon vacancies and 0.88~eV for carbon interstitials are obtained, consistent with literature. The resulting mobility hierarchy governs defect evolution and complex formations. Interstitial vacancy recombination competes with vacancy aggregation into divacancies, influencing the stabilization of spin active defect centers. The study also provides a consistent framework for diffusion analysis in atomistic simulations.