Accurate Prediction of Charge-State-Decay Timescales for NV^- centers in Diamond

The NV^- color center in diamond has broad potential for applications in quantum sensing, computation, and communication. Nonetheless, the tendency of the NV^- to revert to its neutral counterpart the NV⁰, which detrimentally affects its useful characteristics, remains to be fully overcome. We provide an ab initio formalism for accurately estimating the timescales for charge-state decay of the NV^- in diamond and, more generally, of color centers in wide-bandgap semiconductors. Working in the context of thermal equilibrium, our formalism employs hybrid density functional theory calculations to achieve its accuracy. The transition of NV⁻ to NV⁰ in the presence of substitutional N is used to illustrate the method [see Z. Yuan et al., PRR 2, 033263 (2020)].