Theoretical investigation of charge transfer between the N v -Center in diamond and substitutional N and P

Abstract

The nitrogen-vacancy (N V) lattice defect in diamond, consisting of an N substitutional atom and an adjacent C vacancy, is commonly observed in two charge states, negative (N V -) and neutral (N V 0). The N V - defect exhibits spin state-dependent fluorescence and is, therefore, amenable to optical methods for spin-state readout, while the N V 0 is not. Hence, the N V - defect is much more useful for quantum sensing and quantum information processing. However, only N V 0 electroluminescence has been observed, even from centers showing N V - in photoluminescence. In the present work, we use first-principles electronic structure calculations to determine adiabatic charge transition levels for the conversion of N V - to N V 0 in the presence of substitutional N or P impurities, which provide the charge of the N V - center. We find that the adiabatic charge transition levels in the presence of such impurities lie at energies close to or lower than the zero-phonon line of the N V - center and that these energies only decrease as the concentration of N donors increases. This work, therefore, elucidates the absence of observed electroluminescence from the N V - and proposes a path toward observation of the phenomenon.