Optical Properties of NV Centers in Diamond

A nitrogen-vacancy (NV) center is a point defect in diamond which creates interesting optical properties not found in pure diamond that lead to potential applications as a host for a qubit or in photovoltaics. To calculate these optical properties within the framework of DFT, first, after an initial structural relaxation, a self-consistent field (SCF) calculation was performed as the basis for computing transitions to excited states. We then used PBE and HSE06 to generate "empty" states for use in computing the complex dielectric function. Using these data, we calculated the frequency-dependent absorption coefficient for both impurities from both PBE and HSE. The HSE results tended to shift the absorption peaks to higher energies with better agreement with the position of the experimental absorption peaks while also making the peaks taller.