First-principles characterization of nitrogen-related spin-defects in 4H- and 6H-SiC

Optically active spin defects in wide-gap semiconductors are promising platforms for solid-state quantum technologies. For example, in the last few years several defect qubits with long coherence times have been realized in SiC, an attractive material due to its ease of growth and microfabrication, compared to diamond. Recent studies [1-3] have explored the possibility of realizing a nitrogen vacancy (NV) in SiC, in analogy with diamond. We used first-principles calculations based on density functional theory to identify fingerprints of nitrogen related spin-defects in SiC. We computed several properties of point-defects containing nitrogen impurities, including zero-fielding splitting, hyperfine tensors, and zero-phonon lines. In order to analyze the robustness of our results, we conducted sensitivity analysis to establish the effect of pseudopotentials, density functionals and optimized atomistic structures on the computed electronic and spectroscopic properties of the defects.
[1] Zargaleh, S. A. et al. Phys. Rev. B 94, 60102 (2016).
[2] Zargaleh, S. A. et al. Phys. Rev. B 98, 214113 (2018).
[3] Sato, S. et al. J. Appl. Phys. 126, 83105 (2019).