Dynamical excitations of charge states in diamond color centers*

We perform a time-dependent computational study of nitrogen-vacancy centers in diamond under ion irradiation. The negatively charged nitrogen-vacancy (NV^-) centers in diamond are potential candidates for solid-state qubits due to the possibility to manipulate single center's electronic spin states. However, the dynamics of charge transitions between NV centers of different charges, such as the neutral (NV⁰) and the positively charged (NV⁺) centers, are not fully understood. Using time-dependent ab initio calculations, we perform accurate dynamical simulations of ion projectiles propagating near NV centers in diamond and calculate the properties of the defect-related excited states under the projectile impact. We compare our results with a pristine diamond and calculate the dynamical properties of projectile-vacancy coupling for a set of ion projectiles at different velocities. We discuss the quantitative properties of the charge states of nitrogen-vacancy centers at a sufficiently short time-scale that are challenging to approach experimentally.