First-Principles Study of NV Centers Near Extended Defects

We present a density functional theory analysis of the negatively charged nitrogen-vacancy (NV $$^-$$ - ) defect complex located at or in the vicinity of (001) and (111) surfaces as well as 30 $$^{\circ }$$ ∘ and 90 $$^{\circ }$$ ∘ partial glide dislocations in diamond. Formation energies, electronic density of states, geometrical deformations, hyperfine structure and zero-field splitting parameters of NV $$^-$$ - centers in such distorted environments are analyzed. The formation energies of the NV $$^-$$ - centers at the dislocation cores are up to 3 eV reduced compared to the bulk of diamond whereas near the surfaces the change of the formation energy is not significant ( $$\sim $$ ∼ 0.1 eV). For the 30 $$^{\circ }$$ ∘ partial glide dislocation the lowest energy configuration, where the NV $$^-$$ - axis is oriented parallel to the dislocation line, exhibits a stable triplet ground state. This lowest energy configuration of NV $$^-$$ - center at the core of 30 $$^{\circ }$$ ∘ partial glide dislocation has hyperfine constants and ZFS values which deviate by $$3\%$$ 3 % from the NV $$^-$$ - bulk values and is thus an interesting candidate for self-assembled NV $$^-$$ - arrays. These crucial theoretical results required time consuming electronic structure calculations, for which we used the HoreKa computing cluster.