Influence of phosphorus donor on the NV center in diamond: A first-principles study

Abstract

The nitrogen-vacancy (NV) center is a point defect in the diamond, which can be used as a quantum sensor or emitter. It must maintain a negative charge state to utilize its electronic and optical properties. However, enhancing the negative charge stability and avoiding becoming the “dark state” have been challenges in many situations. In this study, we introduced phosphorus atoms as donor elements to provide extra electrons to the NV center to keep its negative charge state through theoretical simulation. We used density functional theory to investigate the electronic and optical properties of the NV center with phosphorus donors in different configurations. We confirmed that the NV center with phosphorus donor could retain its original properties required as a quantum bit. Moreover, in the non-local excitation processes, both in the one-photon and two-photon approaches, including the intersystem crossing (ISC) process, the NV center with phosphorus donor could have a higher resistance to charge conversion (from NV− to NV0) and the “photo-blinking” phenomenon than the NV center with nitrogen donor. Thus, our results suggest that phosphorus can be a promising donor element for improving the stability and functionality of the NV center in quantum applications.