Interaction between NV centers and substituting nitrogen complexes in diamond as a diagnostic probe of the local nitrogen concentration

Abstract

A non-destructive method is proposed for express diagnostics of the local concentration of substituting nitrogen donors (P1 centers) in diamond under environmental conditions by the relative intensity of sideband satellites in the optical detection of magnetic resonance spectrum of the nitrogen vacancy (NV) center. It is shown that the internal satellites which are separated from the central line at a distance of ∼±A/2, where A is the hyperfine (HF) interaction constant for the P1 center, can be explained by the interaction between the NV center and an exchange-coupled P1 pair. The pair of P1 centers strongly interacting with each other leads to the appearance of a state with spin 1 which can be observed in the electron paramagnetic resonance spectra of nitrogen in diamond as additional HF lines. As a result, both interacting spin systems, NV and P1 pair, are characterized by unit spins. The transitions induced by microwave power in two coupled triplet states, which are allowed in spin, lead to the appearance of internal satellites at low microwave powers. These conclusions are confirmed by calculations performed using the EasySpin software package.