Creation of NV- center in type-Ib diamonds by high temperature post-annealing
Ishii Shuya, Saiki Seiichi, Onoda Shinobu +3 more
Negatively charged nitrogen-vacancy (NV-) center in diamond has been paid attention as a highly sensitive detector for magnetic field. The magnetic sensitivity is proportional to the reciprocal of √(NT_2 ), where N is the number of NV centers and T2 is the spin coherence time. To improve the sensitivity, high concentration of NV- centers and extended coherence time are necessary. It is generally known that electron beam irradiation into type-Ib diamond which include high initial concentration of isolated substitutional nitrogen (P1 center) is a useful method to create high concentration of NV- centers. The electron beam irradiation generates vacancies in diamond and the subsequently annealing enables vacancies to diffuse in the lattice. Then diffused vacancies are captured by nitrogen atoms, as a result, NV centers are created. The post annealing has been performed at 1000°C or higher temperature for the purpose of improving the spin properties of NV- centers. In current study, we focused on post-annealing at high temperature to improve magnetic sensitivity of quantum sensing. We investigated annealing temperature and time dependence of the creation behavior of NV centers in type-Ib diamonds to understand appropriate annealing process for enhancing sensitivity of NV- center.
•Nov 16, 2023•0 citations