Production of Nitrogen-Vacancy Color Centers in Diamond Induced by Low Energy Highly Charged Heavy Ion

The nitrogen vacancy (NV⁻) color center in diamond is of great significance in quantum information and quantum sensing because of its excellent quantum coherence quality and stability at room temperature. In this work, the production of NV⁻ color center in diamond was investigated by 2.97 MeV Ar¹¹⁺ highly charged heavy ion irradition combined with the high temperature annealing process. It is found that the yield of NV⁻ color center in diamond samples was significantly increased after the irradiation with a fluence of 1×10¹⁴ ions⁄cm² and annealing. However, at a higher fluence of 1×10¹⁵ ions/cm², the irradiation seriously destroyed the lattice structure of the diamond, resulting in a significant decrease of the NV⁻ color center background. The results show that the concentration of NV⁻ color centers in diamond can be precisely controlled by highly charged ion irradiation, and the annealing temperature and duration also play an important role in regulating the color center yield. Furthermore, the dependence of the NV⁻ color center band gap on temperature and the charge exchange process of highly charged heavy ions in the material were also studied. These works provide experimental and theoretical support for the optimization of ion irradiation technology for the production of color centers in diamond.